Yue Zhao1,2,3†Xin Li2,3,4†
Yanhua Ou1,2,3†
Xiangran Cai5Weijian Huang1Shuhua He1Sisi Liang1
Ning Wang1Linliang Song1,2
Meixia Fang1,2
Hatitao Niu1,2,3*
Jun He1,2,3*- 1Institute of Laboratory Animal Science, Jinan University, Guangzhou, China
- 2Guangzhou Key Laboratory for Germ-free animals and Microbiota Application, Jinan University, Guangzhou, China
- 3Key Laboratory of Viral Pathogenesis and Infection Prevention and Control (Jinan University), Ministry of Education, Guangzhou, China
- 4The Sixth Affiliated Hospital of Jinan University, Dongguan, China
- 5The First Affiliated Hospital of Jinan University, Guangzhou, China
Background: Acute respiratory distress syndrome (ARDS) is a complex syndrome with multiple risk factors that can lead to acute respiratory failure and, in turn, high morbidity and mortality. To clarify the syndrome’s underlying pathomechanisms and develop novel therapies, we have summarized and analyzed a series of chief cause-induced animal models of ARDS.
Aim: Although various animal models have been developed to represent the traits of human ARDS based on clinical symptoms and the yardstick of positive clinical trials, each model has unique features that reflect only part of the characteristics modeled. In response, this review aims to investigate characteristics of ARDS in current animal models and offers new strategies and insights for developing animal models aimed at capturing the features of human ARDS.
Conclusion: This review summarizes the physiological characteristics of animals used in models of ARDS and evaluates the advantages and disadvantages of the chief cause-induced models for modeling human ARDS in animals, for results that can inform the establishment, assessment, and experimental study of ARDS in animal models.
1 Introduction
Acute respiratory distress syndrome (ARDS) is an acute respiratory failure that occurs when exudative fluid accumulates in the pulmonary alveoli of critically ill patients due to increased alveolar–capillary membrane permeability and sustained inflammatory response. Manifesting as rapidly progressive dyspnea, tachypnea, and hypoxemia, ARDS typically emerges within a time frame ranging from a few hours to several days following the precipitating injury or infection (1, 2). In humans, ARDS is characterized by the acute onset of bilateral pulmonary infiltrates and severe hypoxemia with respiratory failure in the absence of cardiogenic pulmonary edema (3). The definition of ARDS, published by the American–European Consensus Conference in 1994 and revised as the Berlin definition in 2011, stipulates four criteria (1): emergence of clinical insult or onset of respiratory symptoms within a week (2), radiographic changes in the form of bilateral opacities (3), edema originating from noncardiogenic pulmonary failure, and (4) severity based on the PaO2/FiO2 ratio, with classifications of mild (i.e., PaO2/FiO2: 200–300), moderate (i.e., PaO2/FiO2: 100–200), and severe (i.e., PaO2/FiO2: ≤100) (3, 4). Nevertheless, limitations in the understanding of ARDS following the publication of the Berlin definition have surfaced, especially regarding noninvasive pulse oximetric methods, the syndrome’s Kigali modification, and the preclinical testing of novel therapeutics and interventions for ARDS (5, 6).
The various causes of ARDS are generally divided into direct pulmonary insults (e.g., pathogenic infection) and indirect insults to the lungs (e.g., sepsis) (7, 8). Because obtaining direct measurements of pathological lung tissue samples in most patients is unrealistic, the diagnosis of ARDS usually depends exclusively on clinical criteria (9). For that reason, various animals—mice, sheep, pigs, rabbits, and even tree shrews, among others—have been employed to investigate lung injury of ARDS. In that context, to elucidate the fundamental mechanisms of ARDS and explore therapeutic approaches to its treatment, using effective, reliable animal models that accurately mimic distinct features of human ARDS is crucial (10–14). To that end, the literature presents an array of values for physiological parameters in commonly used laboratory animal species, and those physiological parameters, as well as anatomical features, should be considered.
In this review, we list the specific physiological parameters of each animal model in order to compare their similarities and differences in pulmonary anatomy as well as physiology and thereby identify models that are ideal for the purpose (Supplementary Material, Supplementary Table S1). Among those parameters, animal size relates to the accuracy of physiological parameters such as arterial blood pressure and arterial oxygen partial pressure. Moreover, when collecting blood samples, large animals are more likely to obtain enough specimens to measure blood gas, plasma inflammatory factors, and neutrophils. Due to such differences between species, differences in their immune systems exist as well, including in pulmonary intravascular macrophages, nitric oxide production, and the presence of hyaline membranes, all of which determine unique species-specific manifestations of lung injury. Beyond that, in research on respiratory systems, aspects of handling, accessibility, costs, and standard reagents, among others, should be considered in features of animal models (Supplementary Material, Supplementary Table S2). Other considerations include the selection of animals that permit cost-effective housing and breeding as well as standard diagnostic procedures. Above all, researchers should thoroughly consider and evaluate the appropriateness of animals’ models and choose the most suitable species for each scientific question, while taking into account the unique advantages and disadvantages of each species. To that purpose, the various references available should be consulted to also review methodologies used and verify the specific species and, when appropriate, the animal model of ARDS used.
This review summarizes aspects of various species currently used to model ARDS using diverse modeling methods. In so doing, we aim to support research on choosing the most appropriate species, including small, medium, and large animals, for investigating ARDS in light of unique objectives. We also provide a comprehensive overview and analysis of the different models established using those species while considering distinct triggers of ARDS in each species.
2 Chief causes and modeling methods of ARDS
The various causes of ARDS are generally divided into direct pulmonary insults (e.g., pathogenic infection) and indirect insults to the lungs (e.g., sepsis) (Supplementary Material, Supplementary Table S3) (7, 8). The most common causes of human ARDS are pneumonia due to infectious (i.e., bacterial, viral, and fungal) triggers of the lung; nonpulmonary sepsis due to non-infectious triggers originating from sources such as the peritoneum, urinary tract, soft tissue, and skin; aspiration of gastric and/or oral and esophageal contents; and major trauma (e.g., blunt or penetrating injuries or burns) (Figure 1) (15–19).
Figure 1. Causes of ARDS.
Although the causes of ARDS are complex, the various triggers usually induce local or systemic inflammation, which results in severe hypoxemia, elevated edema, diffuse alveolar hemorrhage, and the formation of hyaline membranes (20–23). Less common scenarios associated with the development of ARDS include emergency transfusions, acute pancreatitis, drug overdose, near-drowning, hemorrhagic shock or reperfusion injury, and smoke inhalation (24–29). There are also several important risk factors for acute pneumonia, including excessive alcohol consumption, smoking, old age, and chronic lung disease (30, 31). In this review, we systematically analyze the causes associated with pneumonia or nonpulmonary sepsis in ARDS and their pathological characteristics (Table 1).
Table 1. Pathological characteristics of different animal models for ARDS.
2.1 Causes of direct lung injury
According to the criteria of the American–European Consensus Conference, pneumonia, including nosocomial pneumonia, is the most frequent single cause of ARDS among critically ill patients, usually following diffuse alveolar damage (91). Typically triggered by insults induced by chemical agents, infection, smoke, or mechanical injury within one-hit or two-hit direct administration, cases of ARDS involve the alveolar–capillary barrier’s rapid aggravation of the pathophysiology of lung injury and, in turn, symptoms of severe hypoxemia that mimic the properties of human ARDS (92).
2.1.1 One-hit direct insult in animal models
The ideal strategy for establishing ARDS animal models is to induce severe pneumonia via one, two, or multiple combinations. One-hit intratracheal administration with a high dose of LPS, Gram-negative bacteria, viruses, acid (e.g., hydrochloric acid or oleic acid), or smoke can cause severe lung injury as well as neutrophil infiltration, permeability edema, and rapid immune response that mimics a direct response to ARDS (Figure 2) (93–96).
Figure 2. One-hit direct lung injury induced by severe pneumonia in animal models (created with BioRender, https://app.biorender.com/).
2.1.1.1 Intratracheal LPS
LPS modeling, which is widely used in models of small animals (e.g., mice and rats) and medium-sized animals (e.g., rabbits), can imitate acute pulmonary inflammation and a damaged alveoli-capillary barrier and exhibits many mechanisms in the early acute phase, primarily the first 24 h (97–100). Whether observed from histological images or other methods of detection, LPS-induced immune responses resemble those in humans. However, lung injury and physiological data observed in such animal models depend on early detection, which suggests that researchers should use accurate times in their experimental trials. Even so, during investigations of the pathogenesis of ARDS and drug protection in animal models of LPS-induced ARDS, the endpoint has extended to 48–72 h (101). Researchers have also established an ARDS model with the tree shrew, a prosimian species, via one-hit intratracheal LPS and found the comparable advantages. Although that modeling method has been extensively published, physiological data about the early endpoint in animal models induced by high doses of LPS are more closely resemble toxicity-related data.
2.1.1.2 Oleic acid and hydrochloric acid
The symptoms of severe hypoxemia in ARDS models are directly caused by the administration of oleic acid, hydrochloric acid (HCl), bleomycin, or the lavaging of the lungs in animal models. Similar to fatty acids released from fractured bones, those stimuli appear to damage endothelial cells and be responsible for high mortality due to hemodynamic instability (102). Given the economic advantages and applicability of these reagents, it has primarily been used in large animal models for ventilation strategies and lung mechanics. Such models can achieve a low PaO2/FiO2 ratio and typical bilaterally diffuse infiltrates observed in large animal models (103). For example, as shown in a goat model, lung injury induced by oleic acid can lead to severely impaired gas exchange, the deterioration of lung mechanics, and the disruption of the alveolar–capillary barrier (104). In addition, the histological analysis of the lungs of ARDS in animal models has also revealed the infiltration of inflammatory cells, pulmonary edema, and microvascular injury, which could serve as a good models for study of pathophysiology for the syndrome (105). The intratracheal instillation of HCl to mimic direct ARDS via the bronchial aspiration of gastric contents has been widely used in rabbit models (106). Although exhibited decreased arterial oxygen pressure has been observed in small model (rabbit model) induced by HCl, only 10 articles in the database of the National Center for Biotechnology Information (NCBI) pertain to that dynamic.
2.1.1.3 Ventilator-induced ARDS
Mechanical ventilation, first described in the mid-18th century, used animal models that is induced by clinical applications performed in humans and associated with lung injury (107–110). The ventilator-induced lung injury (VILI) model, the most translatable finding in animal models, is influenced by the animal’s size, whether the thorax is open or closed, and whether extrinsic positive end-expiratory pressure is used. Various animal models have been employed, including large mammals (e.g., pigs and sheep) and small rodents (e.g., mice and rats), as well as rabbits (111–114). However, small animals are prone to temperature variability, hemodynamic instability, and limitations of invasive monitoring, which cause unrealistically extended periods of supportive care (115). Therefore, due to its similarity in respiratory anatomy and physiology to humans, the porcine model is usually chosen for one-hit VILI models (116). Unfortunately, the model’s characteristics often last only a few hours. Such short-term models usually induce mild inflammation without any loss of lung function, which limits understandings of the process of ARDS induced by VILI (117, 118).
2.1.1.4 Smoke inhalation
Animal models with ARDS induced by smoke inhalation typically use large animals, although small animals can be induced as well, to evaluate clinical symptoms, pathological lesions, and pathogeneses associated with the clinical identification of indicators of ARDS among clinical patients (119). For instance, in pigs with smoke inhalation-induced lung injury, the PaO2/FiO2 ratio is approximately 208 (50%), while bilateral diffuse infiltrates have been visible on chest X-ray (120). Sheep are another commonly used animal model for ARDS caused by smoke inhalation, which may be a valuable model for studies on pneumonia (121). Although smoke inhalation amounts to genuine intoxication with ARDS in clinical patients, many mechanisms are involved in ventilator-induced lung injury with different time points from clinical manifestations. However, due to disease kinetics, the rapid instillation of high-dose smoke, similar to the rapid infusion of high-pathogens, usually represents a model for intoxication, not pneumonia (122).
2.1.1.5 Intratracheal pathogens
Infectious pneumonia is categorized as viral pneumonia caused by influenza viruses (e.g., H5N1 and H1N1 2009) or coronaviruses (e.g., SARS-CoV-2); bacterial pneumonia caused by Streptococcus pneumoniae or Pseudomonas aeruginosa; or parasitic pneumonia caused by Plasmodium falciparum (53, 123–126). Animal models exhibiting the direct infection of the respiratory tract by pathogens are typically used to study the pathogenesis of pathogens and screening with antigenic drugs, for most models can reveal typical pathological features and immune system responses. Recently, the pandemic caused by SARS-CoV-2 infection has been associated with ARDS in clinical manifestations, sometimes in fatal cases (127). The outbreak of the disease has caused a significant rise in ARDS and heightened public awareness of the syndrome. Partly in response, scientists have developed a genetically modified mouse model expressing the human ACE2 receptor, one that can exhibit severe pneumonia, alveolar necrosis, significant lymphopenia, and neutrophilia in peripheral blood after insult with SARS-CoV-2 (128–130). Nonhuman primates offer another well-established model of infection with SARS-CoV-2, SARS-CoV, and H5N1, which are invariably accompanied by strong pro-inflammatory responses, inflammatory cytokine response, and hyaline membrane formation, all of which are rarely found in rodent models (131, 132). Other commonly used animal models, including hamsters and ferrets, are widely studied to investigate highly pathogenic respiratory viruses, which can mimic one or more characteristics of human ARDS (52, 133–135). However, for biosafety’s sake, it is necessary to conduct experimentation in biosafe laboratories with pathogen limits, and laboratory personnel need to undergo rigorous training to ensure such safety (136–139).
Other intratracheal pathogens are bacteria (e.g., S. pneumoniae and Pseudomonas aeruginosa), which in animals such as mice, rats, and pigs can induce pneumonia within 7 d. Even so, most animals eventually recover (140–142). For a good model of pneumonia-induced ARDS, typical pathological characteristics should be observed during the induction period, including neutrophil infiltration in interstitia and alveoli and epithelial cell injury. The duration of the animal model’s construction depends on bacterial load and activity, which strictly require certain technical operations from researchers.
2.1.1.6 Surfactant depletion
Another direct cause of lung injury is the reduction in levels of pulmonary surfactant, which leads to an increase in surface tension and a decrease in lung compliance during respiration (143). Saline lavage is the most common method that leads to surfactant depletion; it has been widely studied in the context of treating ARDS induced by mechanical ventilation, and pathological and physiological research on the process of ARDS (144). Large and medium-sized animal models (e.g., rabbit, sheep, and pig) are frequently applied to research on lung injury induced by saline lavage with surfactant depletion (145–148). In anesthetized pigs subjected to repeated lung lavages with warmed 0.9% saline (50 mL/kg body weight), severe lung injury has been induced and led to a reproducible deterioration in pulmonary gas exchange and hemodynamics, accompanied by the disadvantageously high recruitability of atelectatic lung tissue (149). Similarly, intratracheally instilled surfactant (100 mg/kg) in newborn piglets has been shown to induce significantly decreased alveolar–arterial oxygen and pulmonary histologic damage, which suggests that such models can be expected to become protective models for drug screening (150).
2.1.1.7 Pulmonary ischemia and reperfusion
Lung injuries induced by pulmonary ischemia and reperfusion (IR) are the most critical mechanism responsible for ARDS in patients following esophagectomy and its leading cause following cardiothoracic surgeries, which results in severe lung dysfunction (151, 152). Generally, lung ischemia is induced by either anoxia or lack of ventilation; thus, the standard methods for blocking blood flow are cross-clamping the vessels via arterial forceps and ligatures and using balloon occluders in the lungs (151). In animals, the lungs of male Sprague–Dawley rats have been flush-perfused with a modified natural bovine surfactant at a dosage of 50 mg/kg body weight, which significantly lessened intra-alveolar edema formation and the development of atelectasis. Pigs, due to their physiological and anatomic similarities to humans, have been identified as suitable models for studying ARDS as well as IR injury, which is the most critical mechanism responsible for developing ARDS in patients after esophagectomy (151).
2.1.1.8 Hyperoxia
Hyperoxia, characterized by excess oxygen in tissues and organs, can induce diffuse pulmonary injuries, vascular leakage, excessive inflammation, and pulmonary edema (153). In research conducted on mice, both CCR2+/+ mice and CCR2−/− mice were exposed to 85% O2, and all died within 6 d. Neutrophils, lymphocytes, and macrophages were significantly elevated, while severe alveolar hemorrhage with a slight thickening of alveolar walls and focal inflammatory cell infiltration was observed in both groups (154). In other research, female C57BL/6J mice were exposed to 90% O2 and exhibited inflammatory infiltrations of neutrophils and other factors, along with edema, thickening of the alveolar walls, and elevated levels of indicators of oxidative stress (153). Similarly, C57BL/6J mice exposed to 95% O2 exhibited a large number of proinflammatory cytokines (e.g., TNF-α, IL-6, and IFN-γ) and increased levels of macrophages and neutrophils infiltrating the lung tissue of mice (155, 156). Despite those findings, the precise mechanism underlying hyperoxia-induced ARDS remains incompletely understood, and effective therapies have not yet been developed.
2.1.2 Two-hit animal models
Patients who suffer from lung injury commonly experience two or multiple hits (i.e., “two-hit” and “multiple-hit,” respectively), which prolongs the immunological response to injury and manifests in clinically significant lung injury (157). In such cases, the singular cause of ARDS models is limited because those models fail to capture the multifactorial pathobiology of clinical ARDS. To better mimic clinical scenarios, two-hit animal models have been established, which are more technically challenging and have been proposed for immune responses with apparent success.
2.1.2.1 Intratracheal LPS or HCl application with mechanical ventilation
Considering mechanical ventilation’s critical role in the care of critically ill patients, serious lung injury is usually initiated by intratracheal LPS application or subacute acid aspiration, with VILI often emerging soon after. Therefore, combining two methods to establish ARDS animal models may closely replicate traits of clinical patients induced by complex causes, as shown in many articles examining various animals. In one study, mice that received LPS 24 h before ventilation with ARDS displayed weight loss, less activity, piloerection, and tachypnea during the first 48 h, consistent with clinical signs of ARDS (158). Similarly, mice that received intratracheal LPS recovered for 20 h, then underwent mechanical ventilation for 4 h, and showed significantly higher inflammatory response levels of neutrophilic infiltration, interstitial edema, and massive alveolar wall damage in the histologic sections of lungs (159). Instead of LPS, HCl was intratracheally administered into the right bronchus of mice, which were subjected to mechanical ventilation after 3 h of surfactant administration; the arterial blood pressure of those mice reached 40 mm Hg, which led to a slow death and the release of inflammatory mediators (i.e., IL-1β and TNF-α) (160). That modeling method is also achievable in rat models, though the duration of the human endpoint cannot be mimicked (161).
The combined method with ventilators in large animal models can quickly induce expected symptoms, including extended life endpoints, hypoxemia, and other symptoms rarely observed in small rodents when severe lung injury is simulated (162–164). A model of highly severe recoverable ARDS was induced in pigs using a two-hit model of lung injury involving 0.9% warm saline lavage and high-volume ventilation (<100 mmHg); however, it lasted only several hours (162). More recently, a multidrug-resistant Pseudomonas aeruginosa strain was intratracheally a multidrug-resistant Pseudomonas aeruginosa strain in pigs after VILI was applied for 3 h, and the ratio of PaO2/FiO2 reached 83 ± 5.45 mmHg, with reduced static compliance, increased pulmonary permeability, and a duration of diffuse alveolar damage exceeding 40 h accompanied by high mortality (165). That modeling method has been used in pigs and sheep, and most associated research has focused on the therapeutic effect of ventilation and the long process of altered breathing. Although the model can present clinical symptoms, especially prolonged symptoms as defined by the new Berlin definition of ARDS, the duration of the symptoms is difficult to control, which poses significant difficulties for studying the syndrome’s pathogenesis.
2.2 Nonpulmonary sepsis
Nonpulmonary triggers can indirectly induce systemic inflammation, including pancreatitis, aspiration of gastric contents, and severe traumatic injuries with shock and multiple transfusions.
2.2.1 Acute pancreatitis
Acute pancreatitis is a crucial gastrointestinal cause of hospital admissions in both humans and dogs. In severe cases of acute pancreatitis, a systemic inflammatory response syndrome, is responsible for up to 60% of mortality. However, because of the condition’s short duration and uncontrollability, it is rarely used to study ARDS (166).
2.2.2 Mesenteric ischemia and reperfusion
Ischemia, associated with anoxia and the absence of nutrient supply, typically causes oxidative damage to tissues, the release of inflammatory mediators, and the influx of inflammatory factors to local and remote organs. In past research, IR has been induced in mice via a 45 min occlusion of the mesenteric artery, followed by reperfusion lasting 2 h. Ultimately, it caused increased myeloperoxidase expression and neutrophils in lung tissue. That modeling approach rapidly produces anticipated symptoms and has a high success rate associated with a significant decrease in arterial oxygenation level at 24 h post-administration (167). In other research, ventilated pigs have been subjected to experimental sepsis via the placement of a peritoneal fecal clot and IR by clamping the superior mesenteric artery for 30 min to achieve more typical clinical symptoms. The markedly decreased oxygen index and P/F ratio, as well as numerous inflammatory, variable physiologic, and blood chemical manifestations, were observed (168). That type of modeling method is rarely showcased in literature in the NCBI database, and surgical modeling may have higher requirements for the operator.
3 Summary
Human ARDS is a serious complication of systemic severe inflammatory response syndrome caused by various severe injuries to the lung, including sepsis, trauma, pneumonia, and smoke inhalation injury, and diffuse alveolar damage (DAD) is a histological manifestation of ARDS. Many neutrophils and macrophages, which are inflammatory cells that play a crucial regulatory role in innate immunity, infiltrate the lung tissue induced by DAD. Although the causes of ARDS are complex, the inflammatory response plays a key role in all animal models of ARDS—for example, infiltration of neutrophils, dysregulated immune-inflammatory responses, and abnormal activation of macrophages. By inhibiting the production of an inflammatory response, immune regulation can relieve the inflammatory cells in ARDS. Here, we summarized key immune cell types (such as pulmonary intravascular macrophages, neutrophils, T cells, and interleukin) and pulmonary pathology of a series of ARDS animals (Table 2).
Table 2. Pulmonary immune and pathology.
4 Conclusion
Due to the difficulties in collecting clinical case data, especially pathological data, animal models have played a significant role in studying ALI. However, the replication of animal models has always been a challenge in research on ARDS. Different species should be considered when studying ARDS depending on the scientific question being investigated. In experiments using the same administration route, different animal species have manifested varying degrees of lung injury caused by different drugs, and even individuals of the same species but different ages have not reacted the same. Those complexities have to be considered when choosing the appropriate ALI/ARDS model. Due to the practical reasons mentioned, mice and rats are the preferred choice for most researchers, especially in studying signaling pathways, immune responses, and pathogenic processes, to explore the mechanism or identify potential therapeutic targets. Although the clinical symptoms of ARDS are not noticeable compared with humans, and the syndrome’s survival time is extremely short, transgenic mice are the first choice when studying ARDS’s pathogenesis, drug screening models, and related gene functions of ARDS. However, anatomical and immune differences and unobservable clinical symptoms between small rodents and humans require using larger animals for experimental validation. In particular, considering the characteristics of commonly used species, especially the anatomical features of the lungs, and the different modeling methods, we have summarized the clinical and pathological characteristics of each species under various modeling methods (Table 1). In this review, primary different modeling methods have been shown to involve various experimental procedures depending on the initial research interests and to have inevitable advantages and disadvantages (Table 3).
Table 3. Pathological characteristics of ARDS in different animal models.
In addition, we summarize the relevance of lung features between humans and ARDS animal models based on the one-hit method. Neutrophil infiltration, epithelial cell damage, alveolar wall thickening is usually observed through intratracheal LPS, pathogens, or chemical reagents on animals, which will help understanding the pathophysiological mechanisms involved in the early process of human ARDS. While hyperoxia isn’t really likely in adult patients, ventilator, surfactant depletion and smoke inhalation is often a cause of lung injury, which is prefer to large animal models to treat the systemic inflammation, refine the mechanism and improve the novel therapeutic method (Table 4).
Table 4. Advantages and disadvantages of each ARDS modeling method.
For instance, small animal models are tractable, which can accommodate mechanisms of disease and allow exploration for therapeutic designs but cannot replicate all the clinical characteristics of ARDS. Large animal models, by comparison, can reproduce clinical features of ARDS and therefore serve as important models to preclinical treatments; however, they are less malleable in mechanistic studies. On top of that, hypoxemia, as the primary criterion of physiological dysfunction in humans, ranks among the biggest technical challenges in models of ARDS in small animals, except tree shrews, but can be actualized in models of large animals. By contrast, rodent models may support the goals of investigating genetic variants and predisposing conditions more readily than large animal models can. Because the animal models currently available cannot fully address human ALI, models need to accommodate at least three of the four domains to qualify as experimental ALI. In this review, we have provided practical, efficient methods for laboratories that lack the time and/or resources to develop complex models that are particularly suitable for studying specific disease processes in ARDS.
When selecting animal models to investigate the pathogenesis of ARDS, the following factors should be considered for selection. First, it is crucial to determine the endpoint in experimental studies. The data collected during experiments usually depend on the design time point or endpoint, which should be listed and clearly defined in the experimental trial design in order to ensure accurate timing. Many experimental endpoints are relative, including the original experiment involving neutrophil fraction in bronchoalveolar lavage cells or slight lung injury with inconspicuous symptoms evaluated by Evans blue, most of which focused on the early immune responses occurring within 24–48 h post-modeling. When trials involve the P/F ratio, wet/dry ratio, or compliance, endpoints should be prolonged, but small animals always die within 72 h in most studies. Large animal models could solve that problem, for the duration of ARDS exceeds 72 h, thereby allowing the detection of predictable clinical symptoms and physiological and biochemical indicators.
Second, the disease’s characteristics are a crucial aspect to consider. In high doses of pathogen-induced pneumonia and sepsis trials, there is a gradual growth pathogen with higher atypical, concomitant immune responses than in human patients. That circumstance may explain why anti-cytokine treatments have failed in humans. The slow administration of pathogen is the preferred modeling method, especially when combined with two-hit or even multiple-hit modeling methods, which can slowly induce lung inflammation and gradually achieve severe lung injury. Animal lungs are strong, redundant, and more importantly, hypoxemia is challenging to induce in healthy animals, especially in small animals, whereas hypoxemia is temporarily observed in large animal models.
Last, ARDS can be a respiratory failure, and the role of experimentation and pharmacotherapy in the treatment strategies of ARDS is minimal. The yardstick for positive clinical trials remains lacking, which may hamper researchers from achieving the requirements for a clinically relevant ARDS model. In fact, most hypotheses regarding human ARDS can be directly assessed in an extensive spectrum of animal models, which can be expected to lead to more acceptable results because of the intact in vivo environment. Although small and medium animals, including mice, rats, tree shrews, and rabbits, are simple, economical, and easy to use, their relevance to the clinic is limited. Conversely, large animals such as dogs, sheep, nonhuman primates, and pigs are more complex, expensive, and complicated to handle. Their advantage lies in their simulation of clinical cases, owing to their similarities with humans, especially in parameter analysis and multiple blood tests. The definition of ARDS has evolved through multiple updates to reflect new clinical insights and practical considerations, meaning patient-tailored strategies hold promise.
Overall, animal models remain helpful and will continue to provide valuable insights into the underlying pathogenesis, progression, and treatment of ARDS, as well as approaches for therapeutic regulation. Animal models should achieve at least three of four domains of ARDS in most mechanistic studies. However, models are recommended to fulfill all four domains in the preclinical testing of new interventions and therapeutics. The causes of human ARDS are complex, which makes it difficult for single animal models to perfectly mimic the symptoms of human ARDS. Researchers should rely on their specific scientific questions in choosing animal models; for example, small models are usually selected for studies on preliminary mechanisms; large animals tend to be evaluated for hypoxemia-related therapeutic strategies and the effectiveness of treatments; and multiple-species animal models should be considered for more reliable experimental results before human clinical trials. With the development of genetic research technology, it is also becoming common to use genetically modified animals for further research on ARDS and its underlying pathogenesis.
Author contributions
JH: Conceptualization, Data curation, Formal Analysis, Investigation, Methodology, Project administration, Validation, Writing – original draft, Writing – review & editing. YZ: Conceptualization, Data curation, Formal Analysis, Investigation, Project administration, Validation, Writing – original draft, Writing – review & editing. XL: Conceptualization, Data curation, Formal Analysis, Writing – original draft, Writing – review & editing. YO: Conceptualization, Data curation, Formal Analysis, Writing – original draft, Writing – review & editing. XC: Conceptualization, Data curation, Formal Analysis, Writing – original draft, Writing – review & editing. WH: Conceptualization, Data curation, Formal Analysis, Writing – original draft, Writing – review & editing. SH: Conceptualization, Formal Analysis, Validation, Writing – original draft, Writing – review & editing. SL: Conceptualization, Data curation, Validation, Writing – original draft, Writing – review & editing. NW: Conceptualization, Formal Analysis, Writing – original draft, Writing – review & editing. LS: Conceptualization, Data curation, Formal Analysis, Writing – original draft, Writing – review & editing. MF: Conceptualization, Data curation, Formal Analysis, Writing – original draft, Writing – review & editing. HN: Conceptualization, Data curation, Formal Analysis, Writing – original draft, Writing – review & editing.
Funding
The author(s) declared financial support was received for this work and/or its publication. This work was supported by the National Natural Science Foundation of China (grant NO. 32273036), the National Key R&D Programs of China (grant NO. 2022YFF0710701 and 2022YFF0710702 to H.N.), Guangzhou Key Research and Development Program (grant NO. 202206010157 to HN), Guanzhou Joint Fund for Key Laboratory (grant numbers 202201020381 to HN), and Medical Joint Fund of Jinan University (grant NO. YXJC2022004 to HN) and Science and Technology Projects in Guangzhou (NO.2023A03J0612).
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
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Supplementary material
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fimmu.2025.1649074/full#supplementary-material
References
1. Fei Q, Bentley I, Ghadiali SN, and Englert JA. Pulmonary drug delivery for acute respiratory distress syndrome. Pulm Pharmacol Ther. (2023) 79:102196. doi: 10.1016/j.pupt.2023.102196
2. Gonzalez-Castro A, Cuenca Fito E, and Gonzalez C. Acute respiratory distress syndrome: a definition on the line. Med Intensiva (Engl Ed). (2023) 47:242. doi: 10.1016/j.medine.2023.01.001
3. Force ADT, Ranieri VM, Rubenfeld GD, Thompson BT, Ferguson ND, Caldwell E, et al. Acute respiratory distress syndrome: the Berlin Definition. JAMA. (2012) 307:2526–33. doi: 10.1001/jama.2012.5669
4. Bernard GR, Artigas A, Brigham KL, Carlet J, Falke K, Hudson L, et al. The American-European Consensus Conference on ARDS. Definitions, mechanisms, relevant outcomes, and clinical trial coordination. Am J Respir Crit Care Med. (1994) 149:818–24. doi: 10.1164/ajrccm.149.3.7509706
5. Matthay MA, Arabi Y, Arroliga AC, Bernard G, Bersten AD, Brochard LJ, et al. A new global definition of acute respiratory distress syndrome. Am J Respir Crit Care Med. (2024) 209:37–47. doi: 10.1164/rccm.202303-0558WS
6. Kulkarni HS, Lee JS, Bastarache JA, Kuebler WM, Downey GP, Albaiceta GM, et al. Update on the features and measurements of experimental acute lung injury in animals: an official american thoracic society workshop report. Am J Respir Cell Mol Biol. (2022) 66:e1–e14. doi: 10.1165/rcmb.2021-0531ST
7. Saguil A and Fargo M. Acute respiratory distress syndrome: diagnosis and management. Am Fam Physician. (2012) 85:352–8.
8. Arber Raviv S, Alyan M, Egorov E, Zano A, Harush MY, Pieters C, et al. Lung targeted liposomes for treating ARDS. J Control Release. (2022) 346:421–33. doi: 10.1016/j.jconrel.2022.03.028
9. Kassirian S, Taneja R, and Mehta S. Diagnosis and management of acute respiratory distress syndrome in a time of COVID-19. Diagnostics (Basel). (2020) 10:1053. doi: 10.3390/diagnostics10121053
10. Bu C, Wang R, Wang Y, Lu B, He S, and Zhao X. Taraxasterol inhibits hyperactivation of macrophages to alleviate the sepsis-induced inflammatory response of ARDS rats. Cell Biochem Biophys. (2022) 80:763–70. doi: 10.1007/s12013-022-01092-2
11. Khoury O, Clouse C, McSwain MK, Applegate J, Kock ND, Atala A, et al. Ferret acute lung injury model induced by repeated nebulized lipopolysaccharide administration. Physiol Rep. (2022) 10:e15400. doi: 10.14814/phy2.15400
12. Puuvuori E, Chiodaroli E, Estrada S, Cheung P, Lubenow N, Sigfridsson J, et al. PET imaging of neutrophil elastase with (11)C-GW457427 in Acute Respiratory Distress Syndrome in pigs. J Nucl Med. (2022) 64:423–9. doi: 10.2967/jnumed.122.264306
13. Ramcharran H, Bates JHT, Satalin J, Blair S, Andrews PL, Gaver DP, et al. Protective ventilation in a pig model of acute lung injury: timing is as important as pressure. J Appl Physiol (1985). (2022) 133:1093–105. doi: 10.1152/japplphysiol.00312.2022
14. Silva IAN, Gvazava N, Bolukbas DA, Stenlo M, Dong J, Hyllen S, et al. A semi-quantitative scoring system for green histopathological evaluation of large animal models of acute lung injury. Bio Protoc. (2022) 12:e4493. doi: 10.21769/BioProtoc.4493
15. Saguil A and Fargo MV. Acute respiratory distress syndrome: diagnosis and management. Am Fam Physician. (2020) 101:730–8.
16. Tran DH, Sameed M, Marciniak ET, and Verceles AC. Human metapneumovirus pneumonia precipitating acute respiratory distress syndrome in an adult patient. Cureus. (2021) 13:e16434. doi: 10.7759/cureus.16434
17. Wick KD, Matthay MA, and Ware LB. Pulse oximetry for the diagnosis and management of acute respiratory distress syndrome. Lancet Respir Med. (2022) 10:1086–98. doi: 10.1016/S2213-2600(22)00058-3
18. Nam H, Jang SH, Hwang YI, Kim JH, Park JY, and Park S. Nonpulmonary risk factors of acute respiratory distress syndrome in patients with septic bacteraemia. Korean J Intern Med. (2019) 34:116–24. doi: 10.3904/kjim.2017.204
20. Bos LDJ and Ware LB. Acute respiratory distress syndrome: causes, pathophysiology, and phenotypes. Lancet. (2022) 400:1145–56. doi: 10.1016/S0140-6736(22)01485-4
21. Su Y, Guo H, and Liu Q. Effects of mesenchymal stromal cell-derived extracellular vesicles in acute respiratory distress syndrome (ARDS): Current understanding and future perspectives. J Leukoc Biol. (2021) 110:27–38. doi: 10.1002/JLB.3MR0321-545RR
22. Diamond M, Peniston HL, Sanghavi D, Mahapatra S, and Doerr C. Acute respiratory distress syndrome (Nursing). Treasure Island (FL: StatPearls (2022).
23. Burey J, Guitard PG, Girard N, Cassiau F, Veber B, and Clavier T. Impact of nursing care on lung functional residual capacity in acute respiratory distress syndrome patients. Nurs Crit Care. (2022) 27:652–7. doi: 10.1111/nicc.12630
24. Beyer A, Rees R, Palmer C, Wessman BT, and Fuller BM. Blood product transfusion in emergency department patients: a case-control study of practice patterns and impact on outcome. Int J Emerg Med. (2017) 10:5. doi: 10.1186/s12245-017-0133-z
25. Zhou MT, Chen CS, Chen BC, Zhang QY, and Andersson R. Acute lung injury and ARDS in acute pancreatitis: mechanisms and potential intervention. World J Gastroenterol. (2010) 16:2094–9. doi: 10.3748/wjg.v16.i17.2094
26. Chakraborty RK and Hamilton RJ. Calcium channel blocker toxicity. Treasure Island (FL: StatPearls (2022).
27. Jin F and Li C. Seawater-drowning-induced acute lung injury: From molecular mechanisms to potential treatments. Exp Ther Med. (2017) 13:2591–8. doi: 10.3892/etm.2017.4302
28. He X, Han B, Mura M, Li L, Cypel M, Soderman A, et al. Anti-human tissue factor antibody ameliorated intestinal ischemia reperfusion-induced acute lung injury in human tissue factor knock-in mice. PloS One. (2008) 3:e1527. doi: 10.1371/journal.pone.0001527
29. Lu Q, Gottlieb E, and Rounds S. Effects of cigarette smoke on pulmonary endothelial cells. Am J Physiol Lung Cell Mol Physiol. (2018) 314:L743–L56. doi: 10.1152/ajplung.00373.2017
30. Gauthier TW and Brown LA. In utero alcohol effects on foetal, neonatal and childhood lung disease. Paediatr Respir Rev. (2017) 21:34–7. doi: 10.1016/j.prrv.2016.08.006
31. Mehta AJ and Guidot DM. Alcohol and the lung. Alcohol Res. (2017) 38:243–54. doi: 10.35946/arcr.v38.2.07
32. Kakiuchi K, Miyasaka T, Takeoka S, Matsuda K, and Harii N. Total alveolar lavage with oxygen fine bubble dispersion directly improves lipopolysaccharide-induced acute respiratory distress syndrome of rats. Sci Rep. (2020) 10:16597. doi: 10.1038/s41598-020-73768-9
33. Engel M, Nowacki RM, Jonker EM, Ophelders D, Nikiforou M, Kloosterboer N, et al. A comparison of four different models of acute respiratory distress syndrome in sheep. Respir Res. (2020) 21:1–11. doi: 10.1186/s12931-020-01475-0
34. Jabaudon M, Blondonnet R, Roszyk L, Bouvier D, Audard J, Clairefond G, et al. Soluble receptor for advanced glycation end-products predicts impaired alveolar fluid clearance in acute respiratory distress syndrome. Am J Respir Crit Care Med. (2015) 192:191–9. doi: 10.1164/rccm.201501-0020OC
35. Abdulnour R-EE, Dalli J, Colby JK, Krishnamoorthy N, Timmons JY, Tan SH, et al. Maresin 1 biosynthesis during platelet–neutrophil interactions is organ-protective. Proc Natl Acad Sci. (2014) 111:16526–31. doi: 10.1073/pnas.1407123111
36. Basoalto R, Damiani LF, Bachmann MC, Fonseca M, Barros M, Soto D, et al. Acute lung injury secondary to hydrochloric acid instillation induces small airway hyperresponsiveness. Am J Trans Res. (2021) 13:12734.
37. Yang Y, Peng Y, and Yang J. Galantamine protects against hydrochloric acid aspirationinduced acute respiratory distress syndrome in rabbits. Trop J Pharm Res. (2018) 17:669–73. doi: 10.4314/tjpr.v17i4.15
38. Liu Y, Tao T, Li W, and Bo Y. Regulating autonomic nervous system homeostasis improves pulmonary function in rabbits with acute lung injury. BMC Pulmonary Med. (2017) 17:1–10. doi: 10.1186/s12890-017-0436-0
39. Holms CA, Otsuki DA, Kahvegian M, Massoco CO, Fantoni DT, Gutierrez PS, et al. Effect of hypertonic saline treatment on the inflammatory response after hydrochloric acid-induced lung injury in pigs. Clinics. (2015) 70:577–83. doi: 10.6061/clinics/2015(08)08
40. Blondonnet R, Paquette B, Audard J, Guler R, Roman F-X, Zhai R, et al. Halogenated agent delivery in porcine model of acute respiratory distress syndrome via an intensive care unit type device. J Visualized Experiments (JoVE). (2020) 163):e61644. doi: 10.3791/61644
41. Audard J, Godet T, Blondonnet R, Joffredo J-B, Paquette B, Belville C, et al. Inhibition of the receptor for advanced glycation end-products in acute respiratory distress syndrome: a randomised laboratory trial in piglets. Sci Rep. (2019) 9:9227. doi: 10.1038/s41598-019-45798-5
42. Callaway DA, Jiang W, Wang L, Lingappan K, and Moorthy B. Oxygen-mediated lung injury in mice lacking the gene for NRF2: Rescue with the cytochrome P4501A-inducer, beta-naphthoflavone (BNF), and differential sex-specific effects. Free Radical Biol Med. (2020) 160:208–18. doi: 10.1016/j.freeradbiomed.2020.07.027
43. Wang L, Lingappan K, Jiang W, Couroucli XI, Welty SE, Shivanna B, et al. Disruption of cytochrome P4501A2 in mice leads to increased susceptibility to hyperoxic lung injury. Free Radical Biol Med. (2015) 82:147–59. doi: 10.1016/j.freeradbiomed.2015.01.019
44. Tung Y-T, Wei C-H, Yen C-C, Lee P-Y, Ware LB, Huang H-E, et al. Aspirin attenuates hyperoxia-induced acute respiratory distress syndrome (ARDS) by suppressing pulmonary inflammation via the NF-κB signaling pathway. Front Pharmacol. (2022) 12:793107. doi: 10.3389/fphar.2021.793107
45. Shah D, Das P, Acharya S, Agarwal B, Christensen DJ, Robertson SM, et al. Small immunomodulatory molecules as potential therapeutics in experimental murine models of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Int J Mol Sci. (2021) 22:2573. doi: 10.3390/ijms22052573
46. Audi SH, Jacobs ER, Taheri P, Ganesh S, and Clough AV. Assessment of protection offered by the NRF2 pathway against hyperoxia-induced acute lung injury in NRF2 knockout rats. Shock. (2022) 57:274–80. doi: 10.1097/SHK.0000000000001882
47. Audi SH, Clough AV, Haworth ST, Medhora M, Ranji M, Densmore JC, et al. 99MTc-hexamethylpropyleneamine oxime imaging for early detection of acute lung injury in rats exposed to hyperoxia or lipopolysaccharide treatment. Shock. (2016) 46:420–30. doi: 10.1097/SHK.0000000000000605
48. Lefrançais E, Mallavia B, Zhuo H, Calfee CS, and Looney MR. Maladaptive role of neutrophil extracellular traps in pathogen-induced lung injury. JCI Insight. (2018) 3:e98178. doi: 10.1172/jci.insight.98178
49. Hou Q, Liu F, Chakraborty A, Jia Y, Prasad A, Yu H, et al. Inhibition of IP6K1 suppresses neutrophil-mediated pulmonary damage in bacterial pneumonia. Sci Trans Med. (2018) 10:eaal4045. doi: 10.1126/scitranslmed.aal4045
50. Diep BA, Chan L, Tattevin P, Kajikawa O, Martin TR, Basuino L, et al. Polymorphonuclear leukocytes mediate Staphylococcus aureus Panton-Valentine leukocidin-induced lung inflammation and injury. Proc Natl Acad Sci. (2010) 107:5587–92. doi: 10.1073/pnas.0912403107
51. Motos A, Yang H, Li Bassi G, Yang M, Meli A, Battaglini D, et al. Inhaled amikacin for pneumonia treatment and dissemination prevention: an experimental model of severe monolateral Pseudomonas aeruginosa pneumonia. Crit Care. (2023) 27:60. doi: 10.1186/s13054-023-04331-x
52. Leist SR, Dinnon KH, Schäfer A, Tse LV, Okuda K, Hou YJ, et al. A mouse-adapted SARS-CoV-2 induces acute lung injury and mortality in standard laboratory mice. Cell. (2020) 183:1070-85. e12. doi: 10.1016/j.cell.2020.09.050
53. Hong W, Yang J, Bi Z, He C, Lei H, Yu W, et al. A mouse model for SARS-CoV-2-induced acute respiratory distress syndrome. Signal transduction targeted Ther. (2021) 6:1. doi: 10.1038/s41392-020-00451-w
54. Salguero FJ, White AD, Slack GS, Fotheringham SA, Bewley KR, Gooch KE, et al. Comparison of rhesus and cynomolgus macaques as an infection model for COVID-19. Nat Commun. (2021) 12:1260. doi: 10.1038/s41467-021-21389-9
55. Kim Y-I, Yu K-M, Koh J-Y, Kim E-H, Kim S-M, Kim EJ, et al. Age-dependent pathogenic characteristics of SARS-CoV-2 infection in ferrets. Nat Commun. (2022) 13:21. doi: 10.1038/s41467-021-27717-3
56. de Vries RD, Schmitz KS, Bovier FT, Predella C, Khao J, Noack D, et al. Intranasal fusion inhibitory lipopeptide prevents direct-contact SARS-CoV-2 transmission in ferrets. Science. (2021) 371:1379–82. doi: 10.1126/science.abf4896
57. Schlottau K, Rissmann M, Graaf A, Schön J, Sehl J, Wylezich C, et al. SARS-CoV-2 in fruit bats, ferrets, pigs, and chickens: an experimental transmission study. Lancet Microbe. (2020) 1:e218–e25. doi: 10.1016/S2666-5247(20)30089-6
58. Chen Z, Yuan Y, Hu Q, Zhu A, Chen F, Li S, et al. SARS-CoV-2 immunity in animal models. Cell Mol Immunol. (2024) 21:119–33. doi: 10.1038/s41423-023-01122-w
59. Sia SF, Yan L-M, Chin AW, Fung K, Choy K-T, Wong AY, et al. Pathogenesis and transmission of SARS-CoV-2 in golden hamsters. Nature. (2020) 583:834–8. doi: 10.1038/s41586-020-2342-5
60. Su X, Bai C, Hong Q, Zhu D, He L, Wu J, et al. Effect of continuous hemofiltration on hemodynamics, lung inflammation and pulmonary edema in a canine model of acute lung injury. Intensive Care Med. (2003) 29:2034–42. doi: 10.1007/s00134-003-2017-3
61. Terzi F, Demirci B, Çınar İ, Alhilal M, and Erol HS. Effects of tocilizumab and dexamethasone on the downregulation of proinflammatory cytokines and upregulation of antioxidants in the lungs in oleic acid-induced ARDS. Respir Res. (2022) 23:249. doi: 10.1186/s12931-022-02172-w
62. Zhao Z, Xu D, Li S, He B, Huang Y, Xu M, et al. Activation of liver X receptor attenuates oleic acid–induced acute respiratory distress syndrome. Am J pathology. (2016) 186:2614–22. doi: 10.1016/j.ajpath.2016.06.018
63. Zhu Y-B, Ling F, Zhang Y-B, Liu A-J, Liu D-H, Qiao C-H, et al. A novel, stable and reproducible acute lung injury model induced by oleic acid in immature piglet. Chin Med J. (2011) 124:4149–54.
64. Sakhatskyy P, Wang Z, Borgas D, Lomas-Neira J, Chen Y, Ayala A, et al. Double-hit mouse model of cigarette smoke priming for acute lung injury. Am J Physiology-Lung Cell Mol Physiol. (2017) 312:L56–67. doi: 10.1152/ajplung.00436.2016
65. Wu X, Hussain M, Syed SK, Saadullah M, Alqahtani AM, Alqahtani T, et al. Verapamil attenuates oxidative stress and inflammatory responses in cigarette smoke (CS)-induced murine models of acute lung injury and CSE-stimulated RAW 264.7 macrophages via inhibiting the NF-κB pathway. Biomedicine Pharmacotherapy. (2022) 149:112783. doi: 10.1016/j.biopha.2022.112783
66. Leiphrakpam PD, Weber HR, McCain A, Matas RR, Duarte EM, and Buesing KL. A novel large animal model of smoke inhalation-induced acute respiratory distress syndrome. Respir Res. (2021) 22:1–15. doi: 10.1186/s12931-021-01788-8
67. Lopez E, Fujiwara O, Nelson C, Winn ME, Clayton RS, Cox RA, et al. Club cell protein, CC10, attenuates acute respiratory distress syndrome induced by smoke inhalation. Shock. (2020) 53:317–26. doi: 10.1097/SHK.0000000000001365
68. Scharffenberg M, Wittenstein J, Ran X, Zhang Y, Braune A, Theilen R, et al. Mechanical power correlates with lung inflammation assessed by positron-emission tomography in experimental acute lung injury in pigs. Front Physiol. (2021) 12:717266. doi: 10.3389/fphys.2021.717266
69. Yilmaz S, Inandiklioglu N, Yildizdas D, Subasi C, Acikalin A, Kuyucu Y, et al. Mesenchymal stem cell: does it work in an experimental model with acute respiratory distress syndrome? Stem Cell Rev Rep. (2013) 9:80–92. doi: 10.1007/s12015-012-9395-2
70. Li L-F, Lee C-S, Liu Y-Y, Chang C-H, Lin C-W, Chiu L-C, et al. Activation of Src-dependent Smad3 signaling mediates the neutrophilic inflammation and oxidative stress in hyperoxia-augmented ventilator-induced lung injury. Respir Res. (2015) 16:1–14. doi: 10.1186/s12931-015-0275-6
71. Wang X-X, Sha X-L, Li Y-L, Li C-L, Chen S-H, Wang J-J, et al. Lung injury induced by short-term mechanical ventilation with hyperoxia and its mitigation by deferoxamine in rats. BMC anesthesiology. (2020) 20:1–10. doi: 10.1186/s12871-020-01089-5
72. Matute-Bello G, Frevert CW, and Martin TR. Animal models of acute lung injury. Am J Physiology-Lung Cell Mol Physiol. (2008) 295:L379–L99. doi: 10.1152/ajplung.00010.2008
73. Fard N, Saffari A, Emami G, Hofer S, Kauczor H-U, and Mehrabi A. Acute respiratory distress syndrome induction by pulmonary ischemia–reperfusion injury in large animal models. J Surg Res. (2014) 189:274–84. doi: 10.1016/j.jss.2014.02.034
74. Lau CL, Zhao Y, Kim J, Kron IL, Sharma A, Yang Z, et al. Enhanced fibrinolysis protects against lung ischemia–reperfusion injury. J Thorac Cardiovasc surgery. (2009) 137:1241–8. doi: 10.1016/j.jtcvs.2008.12.029
75. Van Putte BP, Kesecioglu J, Hendriks JM, Persy VP, van Marck E, Van Schil PE, et al. Cellular infiltrates and injury evaluation in a rat model of warm pulmonary ischemia–reperfusion. Crit Care. (2004) 9:1–8. doi: 10.1186/cc2992
76. Kaslow SR, Reimer JA, Pinezich MR, Hudock MR, Chen P, Morris MG, et al. A clinically relevant model of acute respiratory distress syndrome in human-size swine. Dis Models Mech. (2022) 15:dmm049603. doi: 10.1242/dmm.049603
77. Millar JE, Bartnikowski N, Passmore MR, Obonyo NG, Malfertheiner MV, von Bahr V, et al. Combined mesenchymal stromal cell therapy and extracorporeal membrane oxygenation in acute respiratory distress syndrome. A randomized controlled trial in sheep. Am J Respir Crit Care Med. (2020) 202:383–92. doi: 10.1164/rccm.201911-2143OC
78. Sekiya Y, Shimada K, Takahashi H, Kuga C, Komachi S, Miwa K, et al. Evaluation of a simultaneous adsorption device for cytokines and platelet–neutrophil complexes in vitro and in a rabbit acute lung injury model. Intensive Care Med Experimental. (2021) 9:1–14. doi: 10.1186/s40635-021-00414-7
79. Kobayashi K, Horikami D, Omori K, Nakamura T, Yamazaki A, Maeda S, et al. Thromboxane A2 exacerbates acute lung injury via promoting edema formation. Sci Rep. (2016) 6:32109. doi: 10.1038/srep32109
80. Letsiou E, Rizzo AN, Sammani S, Naureckas P, Jacobson JR, Garcia JG, et al. Differential and opposing effects of imatinib on LPS-and ventilator-induced lung injury. Am J Physiology-Lung Cell Mol Physiol. (2015) 308:L259–L69. doi: 10.1152/ajplung.00323.2014
81. Ding Y, Zhao R, Zhao X, Matthay MA, Nie H-G, and Ji H-L. ENaCs as both effectors and regulators of MiRNAs in lung epithelial development and regeneration. Cell Physiol Biochem. (2017) 44:1120–32. doi: 10.1159/000485417
82. Tian X, Lu B, Huang Y, Zhong W, Lei X, Liu S, et al. Associated effects of lipopolysaccharide, oleic acid, and lung injury ventilator-induced in developing a model of moderate acute respiratory distress syndrome in New Zealand white rabbits. Front Veterinary Science. (2025) 12:1477554. doi: 10.3389/fvets.2025.1477554
83. Krebs J, Pelosi P, Tsagogiorgas C, Zoeller L, Rocco PR, Yard B, et al. Open lung approach associated with high-frequency oscillatory or low tidal volume mechanical ventilation improves respiratory function and minimizes lung injury in healthy and injured rats. Crit Care. (2010) 14:1–14. doi: 10.1186/cc9291
84. Zeng C, Zhu M, Motta-Ribeiro G, Lagier D, Hinoshita T, Zang M, et al. Dynamic lung aeration and strain with positive end-expiratory pressure individualized to maximal compliance versus ARDSNet low-stretch strategy: a study in a surfactant depletion model of lung injury. Crit Care. (2023) 27:307. doi: 10.1186/s13054-023-04591-7
85. Yoshida T, Nakahashi S, Nakamura MAM, Koyama Y, Roldan R, Torsani V, et al. Volume-controlled ventilation does not prevent injurious inflation during spontaneous effort. Am J Respir Crit Care Med. (2017) 196:590–601. doi: 10.1164/rccm.201610-1972OC
86. Mikolka P, Kosutova P, Kolomaznik M, Mateffy S, Nemcova N, Mokra D, et al. Efficacy of surfactant therapy of ARDS induced by hydrochloric acid aspiration followed by ventilator-induced lung injury–an animal study. Physiol Res. (2022) 71:S237. doi: 10.33549/physiolres.935003
87. Fumagalli R and Pesenti A. Unilateral acid aspiration augments the effects of ventilator lung injury in the contralateral lung. Anesthesiology. (2013) 119:642. doi: 10.1097/ALN.0b013e318297d487
88. Xia J, Zhang H, Sun B, Yang R, He H, and Zhan Q. Spontaneous breathing with biphasic positive airway pressure attenuates lung injury in hydrochloric acid-induced acute respiratory distress syndrome. Anesthesiology. (2014) 120:1441–9. doi: 10.1097/ALN.0000000000000259
89. Camprubí-Rimblas M, Tantinyà N, Guillamat-Prats R, Bringué J, Puig F, Gómez MN, et al. Effects of nebulized antithrombin and heparin on inflammatory and coagulation alterations in an acute lung injury model in rats. J Thromb Haemostasis. (2020) 18:571–83. doi: 10.1111/jth.14685
90. Rehberg S, Yamamoto Y, Sousse LE, Jonkam C, Cox RA, Prough DS, et al. Advantages and pitfalls of combining intravenous antithrombin with nebulized heparin and tissue plasminogen activator in acute respiratory distress syndrome. J Trauma Acute Care Surgery. (2014) 76:126–33. doi: 10.1097/TA.0b013e3182ab0785
91. Bernard GR, Artigas A, Brigham KL, Carlet J, Falke K, Hudson L, et al. Report of the American-European Consensus conference on acute respiratory distress syndrome: definitions, mechanisms, relevant outcomes, and clinical trial coordination. Consensus Committee. J Crit Care. (1994) 9:72–81. doi: 10.1016/0883-9441(94)90033-7
92. Bauer TT, Ewig S, Rodloff AC, and Muller EE. Acute respiratory distress syndrome and pneumonia: a comprehensive review of clinical data. Clin Infect Dis. (2006) 43:748–56. doi: 10.1086/506430
93. Burnik C, Altintaş N, Özkaya G, Serter T, Selcuk Z, Firat P, et al. Acute respiratory distress syndrome due to Cryptococcus albidus pneumonia: case report and review of the literature. Sabouraudia. (2007) 45:469–73. doi: 10.1080/13693780701386015
94. Yano S. Acute respiratory distress syndrome due to chronic necrotizing pulmonary aspergillosis. Internal Med. (2007) 46:889–91. doi: 10.2169/internalmedicine.46.0016
95. Short KR, Kroeze EJV, Fouchier RA, and Kuiken T. Pathogenesis of influenza-induced acute respiratory distress syndrome. Lancet Infect diseases. (2014) 14:57–69. doi: 10.1016/S1473-3099(13)70286-X
96. Gonçalves-de-Albuquerque CF, Silva AR, Burth P, Castro-Faria MV, and Castro-Faria-Neto HC. Acute respiratory distress syndrome: role of oleic acid-triggered lung injury and inflammation. Mediators inflammation. (2015) 2015:260465. doi: 10.1155/2015/260465
97. Chen H, Shen Y, Liang Y, Qiu Y, Xu M, and Li C. Selexipag Improves Lipopolysaccharide-Induced ARDS on C57BL/6 Mice by Modulating the cAMP/PKA and cAMP/Epac1 Signaling Pathways. Biol Pharm Bull. (2022) 45:1043–52. doi: 10.1248/bpb.b21-01057
98. Park KH, Chung EY, Choi YN, Jang HY, Kim JS, and Kim GB. Oral administration of Ulmus davidiana extract suppresses interleukin-1beta expression in LPS-induced immune responses and lung injury. Genes Genomics. (2020) 42:87–95. doi: 10.1007/s13258-019-00883-x
99. Shi Y, Zhang B, Chen XJ, Xu DQ, Wang YX, Dong HY, et al. Osthole protects lipopolysaccharide-induced acute lung injury in mice by preventing down-regulation of angiotensin-converting enzyme 2. Eur J Pharm Sci. (2013) 48:819–24. doi: 10.1016/j.ejps.2012.12.031
100. Chimenti L, Morales-Quinteros L, Puig F, Camprubi-Rimblas M, Guillamat-Prats R, Gomez MN, et al. Comparison of direct and indirect models of early induced acute lung injury. Intensive Care Med Exp. (2020) 8:62. doi: 10.1186/s40635-020-00350-y
101. Tang X, Yu Q, Wen X, Qi D, Peng J, He J, et al. Circulating exosomes from lipopolysaccharide-induced ards mice trigger endoplasmic reticulum stress in lung tissue. Shock. (2020) 54:110–8. doi: 10.1097/SHK.0000000000001397
102. Uhlig S and Kuebler WM. Difficulties in modelling ARDS (2017 grover conference series). Pulm Circ. (2018) 8:2045894018766737. doi: 10.1177/2045894018766737
103. Borges AM, Ferrari RS, Thomaz L, Ulbrich JM, Felix EA, Silvello D, et al. Challenges and perspectives in porcine model of acute lung injury using oleic acid. Pulm Pharmacol Ther. (2019) 59:101837. doi: 10.1016/j.pupt.2019.101837
104. Crocker GH and Jones JH. Effects of oleic acid-induced lung injury on oxygen transport and aerobic capacity. Respir Physiol Neurobiol. (2014) 196:43–9. doi: 10.1016/j.resp.2014.02.012
105. Akella A, Sharma P, Pandey R, and Deshpande SB. Characterization of oleic acid-induced acute respiratory distress syndrome model in rat. Indian J Exp Biol. (2014) 52:712–9.
106. Petkova D, Steneva I, Iordanova A, Khristova E, and Lalchev Z. Biochemical and biophysical investigation of liposome action in artificially induced ARDS in rabbit lungs. Akush Ginekol (Sofiia). (2007) 46 Suppl 1:73–80.
107. Beitler JR, Malhotra A, and Thompson BT. Ventilator-induced lung injury. Clin Chest Med. (2016) 37:633–46. doi: 10.1016/j.ccm.2016.07.004
108. Brochard L, Slutsky A, and Pesenti A. Mechanical ventilation to minimize progression of lung injury in acute respiratory failure. Am J Respir Crit Care Med. (2017) 195:438–42. doi: 10.1164/rccm.201605-1081CP
109. Paolone S. Extracorporeal membrane oxygenation (ECMO) for lung injury in severe acute respiratory distress syndrome (ARDS): review of the literature. Clin Nurs Res. (2017) 26:747–62. doi: 10.1177/1054773816677808
110. Slutsky AS. History of mechanical ventilation. From Vesalius to Ventilator-induced Lung Injury. Am J Respir Crit Care Med. (2015) 191:1106–15. doi: 10.1164/rccm.201503-0421PP
111. Rich PB, Reickert CA, Sawada S, Awad SS, Lynch WR, Johnson KJ, et al. Effect of rate and inspiratory flow on ventilator-induced lung injury. J Trauma. (2000) 49:903–11. doi: 10.1097/00005373-200011000-00019
112. Hochhausen N, Biener I, Rossaint R, Follmann A, Bleilevens C, Braunschweig T, et al. Optimizing PEEP by electrical impedance tomography in a porcine animal model of ARDS. Respir Care. (2017) 62:340–9. doi: 10.4187/respcare.05060
113. Wilson MR, Petrie JE, Shaw MW, Hu C, Oakley CM, Woods SJ, et al. High-fat feeding protects mice from ventilator-induced lung injury, via neutrophil-independent mechanisms. Crit Care Med. (2017) 45:e831–e9. doi: 10.1097/CCM.0000000000002403
114. Ju YN, Gong J, Wang XT, Zhu JL, and Gao W. Endothelial colony-forming cells attenuate ventilator-induced lung injury in rats with acute respiratory distress syndrome. Arch Med Res. (2018) 49:172–81. doi: 10.1016/j.arcmed.2018.08.006
115. Yehya N. Lessons learned in acute respiratory distress syndrome from the animal laboratory. Ann Transl Med. (2019) 7:503. doi: 10.21037/atm.2019.09.33
116. Yoshida T, Engelberts D, Otulakowski G, Katira B, Post M, Ferguson ND, et al. Continuous negative abdominal pressure reduces ventilator-induced lung injury in a porcine model. Anesthesiology. (2018) 129:163–72. doi: 10.1097/ALN.0000000000002236
117. Madahar P and Beitler JR. Emerging concepts in ventilation-induced lung injury. F1000Res. (2020) 9:F1000. Faculty Rev-222. doi: 10.12688/f1000research.20576.1
118. Uhlig U and Uhlig S. Ventilation-induced lung injury. Compr Physiol. (2011) 1:635–61. doi: 10.1002/j.2040-4603.2011.tb00335.x
119. Reczynska K, Tharkar P, Kim SY, Wang Y, Pamula E, Chan HK, et al. Animal models of smoke inhalation injury and related acute and chronic lung diseases. Adv Drug Delivery Rev. (2018) 123:107–34. doi: 10.1016/j.addr.2017.10.005
120. Leiphrakpam PD, Weber HR, McCain A, Matas RR, Duarte EM, and Buesing KL. A novel large animal model of smoke inhalation-induced acute respiratory distress syndrome. Respir Res. (2021) 22:198. doi: 10.1186/s12931-021-01788-8
121. Murakami K, Bjertnaes LJ, Schmalstieg FC, McGuire R, Cox RA, Hawkins HK, et al. A novel animal model of sepsis after acute lung injury in sheep. Crit Care Med. (2002) 30:2083–90. doi: 10.1097/00003246-200209000-00022
122. Redl H, Schlag G, and Bahrami S. Animal models of sepsis and shock: a review and lessons learned. Edwin A Deitch. Shock 9(1):1-11 1998. Shock. (1998) 10:442–5.
123. Luyt CE, Combes A, Trouillet JL, Nieszkowska A, and Chastre J. Virus-induced acute respiratory distress syndrome: epidemiology, management and outcome. Presse Med. (2011) 40:e561–8. doi: 10.1016/j.lpm.2011.05.027
124. Ruiz M, Ewig S, Torres A, Arancibia F, Marco F, Mensa J, et al. Severe community-acquired pneumonia. Risk factors and follow-up epidemiology. Am J Respir Crit Care Med. (1999) 160:923–9. doi: 10.1164/ajrccm.160.3.9901107
125. Losert H, Schmid K, Wilfing A, Winkler S, Staudinger T, Kletzmayr J, et al. Experiences with severe P. falciparum malaria in the intensive care unit. Intensive Care Med. (2000) 26:195–201. doi: 10.1007/s001340050045
126. Hong W, Yang J, Bi Z, He C, Lei H, Yu W, et al. A mouse model for SARS-CoV-2-induced acute respiratory distress syndrome. Signal Transduct Target Ther. (2021) 6:1. doi: 10.1038/s41392-020-00451-w
127. Carvelli J, Demaria O, Vely F, Batista L, Chouaki Benmansour N, Fares J, et al. Association of COVID-19 inflammation with activation of the C5a-C5aR1 axis. Nature. (2020) 588:146–50. doi: 10.1038/s41586-020-2600-6
128. Liu B, Cheng Y, Wu Y, Zheng X, Li X, Yang G, et al. Emodin improves alveolar hypercoagulation and inhibits pulmonary inflammation in LPS-provoked ARDS in mice via NF-κB inactivation. Int immunopharmacology. (2020) 88:107020. doi: 10.1016/j.intimp.2020.107020
129. Hassan AO, Case JB, Winkler ES, Thackray LB, Kafai NM, Bailey AL, et al. A SARS-coV-2 infection model in mice demonstrates protection by neutralizing antibodies. Cell. (2020) 182:744–53 e4. doi: 10.1016/j.cell.2020.06.011
130. Israelow B, Song E, Mao T, Lu P, Meir A, Liu F, et al. Mouse model of SARS-CoV-2 reveals inflammatory role of type I interferon signaling. J Exp Med. (2020) 217:e20201241. doi: 10.1084/jem.20201241
131. Smits SL, van den Brand JM, de Lang A, Leijten LM, van Ijcken WF, van Amerongen G, et al. Distinct severe acute respiratory syndrome coronavirus-induced acute lung injury pathways in two different nonhuman primate species. J Virol. (2011) 85:4234–45. doi: 10.1128/JVI.02395-10
132. Fremont JJ, Marini RP, Fox JG, and Rogers AB. Acute respiratory distress syndrome in two rhesus macaques (Macaca mulatta). J Am Assoc Lab Anim Sci. (2008) 47:61–6.
133. Ciurkiewicz M, Armando F, Schreiner T, de Buhr N, Pilchova V, Krupp-Buzimikic V, et al. Ferrets are valuable models for SARS-CoV-2 research. Vet Pathol. (2022) 59:661–72. doi: 10.1177/03009858211071012
134. Golden JW, Li R, Cline CR, Zeng X, Mucker EM, Fuentes-Lao AJ, et al. Hamsters expressing human angiotensin-converting enzyme 2 develop severe disease following exposure to SARS-coV-2. mBio. (2022) 13:e0290621. doi: 10.1128/mbio.02906-21
135. Leist SR, Dinnon KH III, Schäfer A, Tse LV, Okuda K, Hou YJ, et al. A Mouse-Adapted SARS-CoV-2 Induces Acute Lung Injury and Mortality in Standard Laboratory Mice. Cell. (2020) 183:1070–1085.e12. doi: 10.1016/j.cell.2020.09.050
136. Belser JA, Gustin KM, Pearce MB, Maines TR, Zeng H, Pappas C, et al. Pathogenesis and transmission of avian influenza A (H7N9) virus in ferrets and mice. Nature. (2013) 501:556–9. doi: 10.1038/nature12391
137. Wonderlich ER, Swan ZD, Bissel SJ, Hartman AL, Carney JP, O’Malley KJ, et al. Widespread virus replication in alveoli drives acute respiratory distress syndrome in aerosolized H5N1 influenza infection of macaques. J Immunol. (2017) 198:1616–26. doi: 10.4049/jimmunol.1601770
140. Rocco PRM and Nieman GF. ARDS: what experimental models have taught us. Intensive Care Med. (2016) 42:806–10. doi: 10.1007/s00134-016-4268-9
141. Choi G, Hofstra JJ, Roelofs JJ, Rijneveld AW, Bresser P, van der Zee JS, et al. Antithrombin inhibits bronchoalveolar activation of coagulation and limits lung injury during Streptococcus pneumoniae pneumonia in rats. Crit Care Med. (2008) 36:204–10. doi: 10.1097/01.CCM.0000292012.87482.F4
142. Sperber J, Nyberg A, Lipcsey M, Melhus A, Larsson A, Sjolin J, et al. Protective ventilation reduces Pseudomonas aeruginosa growth in lung tissue in a porcine pneumonia model. Intensive Care Med Exp. (2017) 5:40. doi: 10.1186/s40635-017-0152-3
143. Kamga Gninzeko FJ, Valentine MS, Tho CK, Chindal SR, Boc S, Dhapare S, et al. Excipient enhanced growth aerosol surfactant replacement therapy in an in vivo rat lung injury model. J Aerosol Med Pulm Drug Deliv. (2020) 33:314–22. doi: 10.1089/jamp.2020.1593
144. Crockett DC, Tran MC, Formenti F, Cronin JN, Hedenstierna G, Larsson A, et al. Validating the inspired sinewave technique to measure the volume of the ‘baby lung’ in a porcine lung-injury model. Br J Anaesth. (2020) 124:345–53. doi: 10.1016/j.bja.2019.11.030
145. Kamiyama J, Jesmin S, Sakuramoto H, Shimojo N, Islam MM, Khatun T, et al. Assessment of circulatory and pulmonary endothelin-1 levels in a lavage-induced surfactant-depleted lung injury rabbit model with repeated open endotracheal suctioning and hyperinflation. Life Sci. (2014) 118:370–8. doi: 10.1016/j.lfs.2014.04.001
146. Yang Y, Huang Y, Tang R, Chen Q, Hui X, Li Y, et al. Optimization of positive end-expiratory pressure by volumetric capnography variables in lavage-induced acute lung injury. Respiration. (2014) 87:75–83. doi: 10.1159/000354787
147. de Prost N, Feng Y, Wellman T, Tucci MR, Costa EL, Musch G, et al. 18F-FDG kinetics parameters depend on the mechanism of injury in early experimental acute respiratory distress syndrome. J Nucl Med. (2014) 55:1871–7. doi: 10.2967/jnumed.114.140962
148. Sanchez Luna M, Santos Gonzalez M, and Tendillo Cortijo F. High-frequency oscillatory ventilation combined with volume guarantee in a neonatal animal model of respiratory distress syndrome. Crit Care Res Pract. (2013) 2013:593915. doi: 10.1155/2013/593915
149. Russ M, Kronfeldt S, Boemke W, Busch T, Francis RC, and Pickerodt PA. Lavage-induced surfactant depletion in pigs as a model of the acute respiratory distress syndrome (ARDS). J Vis Exp. (2016) (115):53610. doi: 10.3791/53610
150. Yang CF, Jeng MJ, Soong WJ, Lee YS, Tsao PC, and Tang RB. Acute pathophysiological effects of intratracheal instillation of budesonide and exogenous surfactant in a neonatal surfactant-depleted piglet model. Pediatr Neonatol. (2010) 51:219–26. doi: 10.1016/S1875-9572(10)60042-3
151. Fard N, Saffari A, Emami G, Hofer S, Kauczor HU, and Mehrabi A. Acute respiratory distress syndrome induction by pulmonary ischemia-reperfusion injury in large animal models. J Surg Res. (2014) 189:274–84. doi: 10.1016/j.jss.2014.02.034
152. Chen K, Xu Z, Liu Y, Wang Z, Li Y, Xu X, et al. Irisin protects mitochondria function during pulmonary ischemia/reperfusion injury. Sci Transl Med. (2017) 9:eaao6298. doi: 10.1126/scitranslmed.aao6298
153. Bhandari V and Elias JA. Cytokines in tolerance to hyperoxia-induced injury in the developing and adult lung. Free Radic Biol Med. (2006) 41:4–18. doi: 10.1016/j.freeradbiomed.2006.01.027
154. Okuma T, Terasaki Y, Sakashita N, Kaikita K, Kobayashi H, Hayasaki T, et al. MCP-1/CCR2 signalling pathway regulates hyperoxia-induced acute lung injury via nitric oxide production. Int J Exp Pathol. (2006) 87:475–83. doi: 10.1111/j.1365-2613.2006.00502.x
155. Ye Y, Lin P, Zhang W, Tan S, Zhou X, Li R, et al. DNA repair interacts with autophagy to regulate inflammatory responses to pulmonary hyperoxia. J Immunol. (2017) 198:2844–53. doi: 10.4049/jimmunol.1601001
156. Yen CC, Chang WH, Tung MC, Chen HL, Liu HC, Liao CH, et al. Lactoferrin protects hyperoxia-induced lung and kidney systemic inflammation in an in vivo imaging model of NF-kappaB/luciferase transgenic mice. Mol Imaging Biol. (2020) 22:526–38. doi: 10.1007/s11307-019-01390-x
157. Lang JD and Hickman-Davis JM. One-hit, two-hit … is there really any benefit? Clin Exp Immunol. (2005) 141:211–4. doi: 10.1111/j.1365-2249.2005.02853.x
158. Hoegl S, Burns N, Angulo M, Francis D, Osborne CM, Mills TW, et al. Capturing the multifactorial nature of ARDS - “Two-hit” approach to model murine acute lung injury. Physiol Rep. (2018) 6:e13648. doi: 10.14814/phy2.13648
159. Rizzo AN, Sammani S, Esquinca AE, Jacobson JR, Garcia JG, Letsiou E, et al. Imatinib attenuates inflammation and vascular leak in a clinically relevant two-hit model of acute lung injury. Am J Physiol Lung Cell Mol Physiol. (2015) 309:L1294–304. doi: 10.1152/ajplung.00031.2015
160. Zambelli V, Bellani G, Amigoni M, Grassi A, Scanziani M, Farina F, et al. The effects of exogenous surfactant treatment in a murine model of two-hit lung injury. Anesth Analg. (2015) 120:381–8.
161. Krebs J, Pelosi P, Tsagogiorgas C, Zoeller L, Rocco PR, Yard B, et al. Open lung approach associated with high-frequency oscillatory or low tidal volume mechanical ventilation improves respiratory function and minimizes lung injury in healthy and injured rats. Crit Care. (2010) 14:R183. doi: 10.1186/cc9291
162. Katira BH, Osada K, Engelberts D, Bastia L, Damiani LF, Li X, et al. Positive end-expiratory pressure, pleural pressure, and regional compliance during pronation: an experimental study. Am J Respir Crit Care Med. (2021) 203:1266–74. doi: 10.1164/rccm.202007-2957OC
163. Araos J, Alegria L, Garcia P, Cruces P, Soto D, Erranz B, et al. Near-apneic ventilation decreases lung injury and fibroproliferation in an acute respiratory distress syndrome model with extracorporeal membrane oxygenation. Am J Respir Crit Care Med. (2019) 199:603–12. doi: 10.1164/rccm.201805-0869OC
164. Yoshida T, Piraino T, Lima CAS, Kavanagh BP, Amato MBP, and Brochard L. Regional ventilation displayed by electrical impedance tomography as an incentive to decrease positive end-expiratory pressure. Am J Respir Crit Care Med. (2019) 200:933–7. doi: 10.1164/rccm.201904-0797LE
165. Barbeta E, Arrieta M, Motos A, Bobi J, Yang H, Yang M, et al. A long-lasting porcine model of ARDS caused by pneumonia and ventilator-induced lung injury. Crit Care. (2023) 27:239. doi: 10.1186/s13054-023-04512-8
166. Vrolyk V and Singh B. Animal models to study the role of pulmonary intravascular macrophages in spontaneous and induced acute pancreatitis. Cell Tissue Res. (2020) 380:207–22. doi: 10.1007/s00441-020-03211-y
167. Thais Fantozzi E, Rodrigues-Garbin S, Yamamoto Ricardo-da-Silva F, Oliveira-Filho RM, Spina D, Tavares-de-Lima W, et al. Acute lung injury induced by intestinal ischemia and reperfusion is altered in obese female mice. Pulm Pharmacol Ther. (2018) 49:54–9. doi: 10.1016/j.pupt.2018.01.005
168. Sadowsky D, Nieman G, Barclay D, Mi Q, Zamora R, Constantine G, et al. Impact of chemically-modified tetracycline 3 on intertwined physiological, biochemical, and inflammatory networks in porcine sepsis/ARDS. Int J Burns Trauma. (2015) 5:22–35.
169. Wang K, Wang M, Liao X, Gao S, Hua J, Wu X, et al. Locally organised and activated Fth1(hi) neutrophils aggravate inflammation of acute lung injury in an IL-10-dependent manner. Nat Commun. (2022) 13:7703. doi: 10.1038/s41467-022-35492-y
170. McElvaney OJ, Curley GF, Rose-John S, and McElvaney NG. Interleukin-6: obstacles to targeting a complex cytokine in critical illness. Lancet Respir Med. (2021) 9:643–54. doi: 10.1016/S2213-2600(21)00103-X
171. Dahmer MK, Yang G, Zhang M, Quasney MW, Sapru A, Weeks HM, et al. Identification of phenotypes in paediatric patients with acute respiratory distress syndrome: a latent class analysis. Lancet Respir Med. (2022) 10:289–97. doi: 10.1016/S2213-2600(21)00382-9
172. Flower L, Vozza EG, Bryant CE, and Summers C. Role of inflammasomes in acute respiratory distress syndrome. thorax. (2025) 80:255–63. doi: 10.1136/thorax-2024-222596
173. Mohammed Ismail W, Fernandez JA, Binder M, Lasho TL, Kim M, Geyer SM, et al. Single-cell multiomics reveal divergent effects of DNMT3A-and TET2-mutant clonal hematopoiesis in inflammatory response. Blood Advances. (2025) 9:402–16. doi: 10.1182/bloodadvances.2024014467
174. Blot P-L, Chousterman BG, Santafè M, Cartailler J, Pacheco A, Magret M, et al. Subphenotypes in patients with acute respiratory distress syndrome treated with high-flow oxygen. Crit Care. (2023) 27:419. doi: 10.1186/s13054-023-04687-0
175. Agouridakis P, Kyriakou D, Alexandrakis M, Perisinakis K, Karkavitsas N, and Bouros D. Association between increased levels of IL-2 and IL-15 and outcome in patients with early acute respiratory distress syndrome. Eur J Clin Invest. (2002) 32:862–7. doi: 10.1046/j.1365-2362.2002.01081.x
176. Karagiannis F, Peukert K, Surace L, Michla M, Nikolka F, Fox M, et al. Impaired ketogenesis ties metabolism to T cell dysfunction in COVID-19. Nature. (2022) 609:801–7. doi: 10.1038/s41586-022-05128-8
177. Shih L-J, Yang C-C, Liao M-T, Lu K-C, Hu W-C, and Lin C-P. An important call: Suggestion of using IL-10 as therapeutic agent for COVID-19 with ARDS and other complications. Virulence. (2023) 14:2190650. doi: 10.1080/21505594.2023.2190650
178. Xie B, Wang M, Zhang X, Zhang Y, Qi H, Liu H, et al. Gut-derived memory γδ T17 cells exacerbate sepsis-induced acute lung injury in mice. Nat Commun. (2024) 15:6737. doi: 10.1038/s41467-024-51209-9
179. Fears AC, Walker EM, Chirichella N, Slisarenko N, Merino KM, Golden N, et al. The dynamics of γδ T cell responses in nonhuman primates during SARS-CoV-2 infection. Commun Biol. (2022) 5:1380. doi: 10.1038/s42003-022-04310-y
180. Rotar EP, Haywood NS, Mehaffey JH, Money DT, Ta HQ, Stoler MH, et al. Gastric aspiration and ventilator-induced model of acute respiratory distress syndrome in swine. J Surg Res. (2022) 280:280–7. doi: 10.1016/j.jss.2022.07.023
181. Collins P, Weg V, Faccioli L, Watson M, Moqbel R, and Williams T. Eosinophil accumulation induced by human interleukin-8 in the Guinea-pig in vivo. Immunology. (1993) 79:312.
182. Endo Y, Miyasho T, Endo K, Kawamura Y, Miyoshi K, Takegawa R, et al. Diagnostic value of transpulmonary thermodilution measurements for acute respiratory distress syndrome in a pig model of septic shock. J Trans Med. (2022) 20:617. doi: 10.1186/s12967-022-03793-x
183. Li Y, Wang G, Liu Y, Tu Y, He Y, Wang Z, et al. Identification of apoptotic cells in the thymus of piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus. Virus Res. (2014) 189:29–33. doi: 10.1016/j.virusres.2014.04.011
184. Quijada H, Bermudez T, Kempf CL, Valera DG, Garcia AN, Camp SM, et al. Endothelial eNAMPT amplifies pre-clinical acute lung injury: efficacy of an eNAMPT-neutralising monoclonal antibody. Eur Respir J. (2021) 57:2002536. doi: 10.1183/13993003.02536-2020
185. Meyerholz DK, Grubor B, Lazic T, Gallup JM, De Macedo MM, McCray P, et al. Monocytic/macrophagic pneumonitis after intrabronchial deposition of vascular endothelial growth factor in neonatal lambs. Veterinary pathology. (2006) 43:689–94. doi: 10.1183/13993003.02536-2020
186. Cox RA, Burke AS, Traber DL, Herndon DN, and Hawkins HK. Production of pro-inflammatory polypeptides by airway mucous glands and its potential significance. Pulmonary Pharmacol Ther. (2007) 20:172–7. doi: 10.1016/j.pupt.2006.03.013
187. Zhao F, Wang W, Fang Y, Li X, Shen L, Cao T, et al. Molecular mechanism of sustained inflation in acute respiratory distress syndrome. J Trauma Acute Care Surgery. (2012) 73:1106–13. doi: 10.1097/TA.0b013e318265cc6f
188. Puerta-Guardo H, Raya-Sandino A, González-Mariscal L, Rosales VH, Ayala-Dávila J, Chávez-Mungía B, et al. The cytokine response of U937-derived macrophages infected through antibody-dependent enhancement of dengue virus disrupts cell apical-junction complexes and increases vascular permeability. J virology. (2013) 87:7486–501. doi: 10.1128/JVI.00085-13
189. Syrjä P, Saari S, Rajamäki M, Saario E, and Järvinen A-K. Pulmonary histopathology in Dalmatians with familial acute respiratory distress syndrome (ARDS). J Comp pathology. (2009) 141:254–9. doi: 10.1016/j.jcpa.2009.05.008
190. Kosutova P, Mikolka P, Mokra D, and Calkovska A. Anti-inflammatory activity of non-selective PDE inhibitor aminophylline on the lung tissue and respiratory parameters in animal model of ARDS. J Inflammation. (2023) 20:10. doi: 10.1186/s12950-023-00337-y
191. Lyu J, Narum DE, Baldwin SL, Larsen SE, Bai X, Griffith DE, et al. Understanding the development of tuberculous granulomas: insights into host protection and pathogenesis, a review in humans and animals. Front Immunol. (2024) 15:1427559. doi: 10.3389/fimmu.2024.1427559
192. Zhao C, Yu S, Li J, Xu W, and Ge R. Changes in IL-4 and IL-13 expression in allergic-rhinitis treated with hydrogen-rich saline in Guinea-pig model. Allergologia Immunopathologia. (2017) 45:350–5. doi: 10.1016/j.aller.2016.10.007
193. Li X, Zhou Z, Liu W, Fan Y, Luo Y, Li K, et al. Chinese tree shrew: a permissive model for in vitro and in vivo replication of human adenovirus species B. Emerging Microbes infections. (2021) 10:424–38. doi: 10.1080/22221751.2021.1895679
194. Li X, Liu W, Qiu S, Xu D, Zhou Z, Tian X, et al. Construction of real-time polymerase chain reaction detection for infection-related cytokines of tree shrew. Sheng wu yi xue Gong Cheng xue za zhi= J Biomed Engineering= Shengwu Yixue Gongchengxue Zazhi. (2019) 36:407–13. doi: 10.7507/1001-5515.201801036
195. Zhang D, Dong B, Chen J, Zhang Z, Zeng W, Liao L, et al. Fecal microbiota transplantation modulates th17/treg balance via JAK/STAT pathway in ARDS rats. Advanced Biol. (2025) 9:e00028. doi: 10.1002/adbi.202500028
196. Zhang L and Li J. Glabridin reduces lipopolysaccharide-induced lung injury in rats by inhibiting p38 mitogen activated protein kinase/extracellular regulated protein kinases signaling pathway. Zhonghua yi xue za zhi. (2016) 96:3893–7. doi: 10.3760/cma.j.issn.0376-2491.2016.48.009
197. Xu H, Xie J, Lei Y, Cui Q, and Jin M. Anti-inflammatory effects of penehyclidine hydrochloride on acute respiratory distress syndrome in rats. Zhonghua wei Zhong Bing ji jiu yi xue. (2018) 30:764–7. doi: 10.3760/cma.j.issn.2095-4352.2018.08.010
198. Lang S, Li L, Wang X, Sun J, Xue X, Xiao Y, et al. CXCL10/IP-10 neutralization can ameliorate lipopolysaccharide-induced acute respiratory distress syndrome in rats. PloS One. (2017) 12:e0169100. doi: 10.1371/journal.pone.0169100
199. Wang C, Liu P, Luo J, Ding H, Gao Y, Sun L, et al. Geldanamycin reduces acute respiratory distress syndrome and promotes the survival of mice infected with the highly virulent H5N1 influenza virus. Front Cell Infection Microbiol. (2017) 7:267. doi: 10.3389/fcimb.2017.00267
200. Paukner S, Kimber S, Cumper C, Rea-Davies T, Sueiro Ballesteros L, Kirkham C, et al. In vivo immune-modulatory activity of lefamulin in an influenza virus A (H1N1) infection model in mice. Int J Mol Sci. (2024) 25:5401. doi: 10.3390/ijms25105401
201. Tan W, Zhang C, Liu J, and Miao Q. Regulatory T-cells promote pulmonary repair by modulating T helper cell immune responses in lipopolysaccharide-induced acute respiratory distress syndrome. Immunology. (2019) 157:151–62. doi: 10.1111/imm.13060
202. Tan W, Zhang B, Liu X, Zhang C, Liu J, and Miao Q. Interleukin-33-Dependent accumulation of regulatory T cells mediates pulmonary epithelial regeneration during acute respiratory distress syndrome. Front Immunol. (2021) 12:653803. doi: 10.3389/fimmu.2021.653803
203. Kudo D, Toyama M, Aoyagi T, Akahori Y, Yamamoto H, Ishii K, et al. Involvement of high mobility group box 1 and the therapeutic effect of recombinant thrombomodulin in a mouse model of severe acute respiratory distress syndrome. Clin Exp Immunol. (2013) 173:276–87. doi: 10.1111/cei.12106
204. Schneberger D, Aharonson-Raz K, and Singh B. Pulmonary intravascular macrophages and lung health: what are we missing? Am J Physiol Lung Cell Mol Physiol. (2012) 302:L498–503. doi: 10.1152/ajplung.00322.2011I012
205. Al-Husinat L, Azzam S, Al Sharie S, Araydah M, Battaglini D, Abushehab S, et al. A narrative review on the future of ARDS: evolving definitions, pathophysiology, and tailored management. Crit Care (London England). (2025) 29:88. doi: 10.1186/s13054-025-05291-0
206. Zhang M, Sun J, Yu H, Han X, Wang J, and Wang J. Lipopolysaccharide-induced acute respiratory distress syndrome and protective effects of curcumin in rabbits. Acad J OF Chin PLA Med SCHOOL. (2023) 44:33–7, 42. doi: 10.3969/j.issn.2095-5227.2023.01.007
207. Gautam A, Boyd DF, Nikhar S, Zhang T, Siokas I, Van de Velde L-A, et al. Necroptosis blockade prevents lung injury in severe influenza. Nature. (2024) 628:835–43. doi: 10.1038/s41586-024-07265-8
208. Feng Y, Xia W, Ji K, Lai Y, Feng Q, Chen H, et al. Hemogram study of an artificially feeding tree shrew (Tupaia belangeri chinensis). Exp animals. (2020) 69:80–91. doi: 10.1538/expanim.19-0079
209. He J, Zhao Y, Fu Z, Chen L, Hu K, Lin X, et al. A novel tree shrew model of lipopolysaccharide-induced acute respiratory distress syndrome. J Advanced Res. (2024) 56:157–65. doi: 10.1016/j.jare.2023.03.009
210. Larson-Casey JL, He C, Che P, Wang M, Cai G, Y-i K, et al. Technical advance: The use of tree shrews as a model of pulmonary fibrosis. PloS One. (2020) 15:e0241323. doi: 10.1371/journal.pone.0241323
211. Sueishi K, Tanaka K, and Oda T. Role of fibrinolysis in development of hyaline membrane disease in newborn rabbits. Virchows Archiv A. (1978) 378:247–57. doi: 10.1007/BF00427363
212. Banstola A and Reynolds JN. The sheep as a large animal model for the investigation and treatment of human disorders. Biology. (2022) 11:1251. doi: 10.3390/biology11091251
213. Almeida D, Barletta M, Mathews L, Graham L, and Quandt J. Comparison between invasive blood pressure and a non-invasive blood pressure monitor in anesthetized sheep. Res veterinary science. (2014) 97:582–6. doi: 10.1016/j.rvsc.2014.10.004
214. Li M, Wang YS, Elwell-Cuddy T, Baynes RE, Tell LA, Davis JL, et al. Physiological parameter values for physiologically based pharmacokinetic models in food-producing animals. Part III: Sheep and goat. J veterinary Pharmacol Ther. (2021) 44:456–77. doi: 10.1111/jvp.12938
215. Kolobow T, Solca M, Presenti A, Buckhold D, and Pierce J. The prevention of hyaline membrane disease (HMD) in the preterm fetal lamb through the static inflation of the lungs: the conditioning of the fetal lungs. ASAIO J. (1980) 26:567–72.
216. Highland MA, Schneider DA, White SN, Madsen-Bouterse SA, Knowles DP, and Davis WC. Differences in leukocyte differentiation molecule abundances on domestic sheep (Ovis aries) and bighorn sheep (Ovis canadensis) neutrophils identified by flow cytometry. Comp Immunology Microbiol Infect Diseases. (2016) 46:40–6. doi: 10.1016/j.cimid.2016.04.006
217. Fu W, Qin X, You C, Meng Q, Zhao Y, and Zhang Y. High frequency oscillatory ventilation versus conventional ventilation in a newborn piglet model with acute lung injury. Respir Care. (2013) 58:824–30. doi: 10.4187/respcare.01972
218. Araos J, Alegría L, García P, Damiani F, Tapia P, Soto D, et al. Extracorporeal membrane oxygenation improves survival in a novel 24-hour pig model of severe acute respiratory distress syndrome. Am J Trans Res. (2016) 8:2826. doi: 10.1152/ajplung.00322.2011
219. Lin Z, Li M, Wang YS, Tell LA, Baynes RE, Davis JL, et al. Physiological parameter values for physiologically based pharmacokinetic models in food-producing animals. Part I: Cattle swine. J veterinary Pharmacol Ther. (2020) 43:385–420. doi: 10.1111/jvp.12861
Keywords: acute respiratory distress syndrome (ARDS), animal model, modeling design and assessment, one-hit, two-hit
Citation: Zhao Y, Li X, Ou Y, Cai X, Huang W, He S, Liang S, Wang N, Song L, Fang M, Niu H and He J (2025) Experimental animal models of acute respiratory distress syndrome: one-hit and two-hit establishment application. Front. Immunol. 16:1649074. doi: 10.3389/fimmu.2025.1649074
Received: 18 June 2025; Accepted: 24 November 2025; Revised: 20 November 2025;
Published: 11 December 2025.
Edited by:
Giuseppe Murdaca, University of Genoa, ItalyReviewed by:
Eleonore Fröhlich, Medical University of Graz, AustriaJianbao Wang, Second Hospital of Anhui Medical University, China
Copyright © 2025 Zhao, Li, Ou, Cai, Huang, He, Liang, Wang, Song, Fang, Niu and He. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Hatitao Niu, aHRuaXVAam51LmVkdS5jbg==; Jun He, aGVqdW5Aam51LmVkdS5jbg==
†These authors have contributed equally to this work