Innate lymphoid cells (ILC) are a heterogeneous population of cells that was recently discovered in 2008 as a new group of cells present in both humans and mice and has been extensively studied over the past few years. According to the currently accepted nomenclature, these cells are divided into three main groups, depending on their pattern of expression of transcription factors and cytokines, being: group 1, including ILC1 and NK cells, mainly by the expression of T-bet and interferon (IFN)-?, resembling CD8 and Th1 cells; group 2, cells that mainly express GATA3, and cytokine IL-4, IL-5, and IL-13, similar to Th2 cells; and group 3, composed of cells expressing ROR?t that mainly produce IL-22 and IL-17, analogous to Th17 cells. Although their effector functions are close to those performed by adaptive T cells, they are considered components of the innate system because they do not recognize specific antigens – as they do not have TCR – and their activation depends mainly on the binding of cytokines and alarmins produced by other cells.
Furthermore, ILCs are mainly found along host barriers, such as skin and mucosa, and play a crucial role as the first line of defense, responding promptly with cytokine production and aiding communication between other immune and non-immune cells. Indeed, ILCs are involved in the pathogenesis of many microbiota-instructed disorders, including inflammatory bowel diseases (IBD), cancer, autoimmune diseases, allergy, asthma, obesity, and other metabolic diseases. It is already known that the commensal microbiota is extremely important for the host and, throughout its life, molds, and assists in some physiological functions, such as nutrient absorption, metabolism, and development of the immune system. However, the amount and diversity of this microbial community, as well as its derived metabolites, can vary between individuals due to several factors, including, mainly, age, diet, and metabolic/genetic disorders, and is strongly related to increased susceptibility to opportunistic infections. Considering the fact that these ILCs play a relevant role in the development of barrier immunity and a wide range of interactions with the microbiota and other cells, there are still many unanswered questions about how this newly described group of cells interferes with microbial and host communication.
The aim of this research topic is to explore and better understand the molecular insights of crosstalk between the microbiota and innate lymphoid cells on homeostasis and its impact during disease/infection. We wish to improve knowledge about the mechanisms that bacterial species or specific microbial communities have that influence the function of ILCs and control host immunity. Indeed, better identification of these groups of organisms will help to achieve microbial therapeutic targets through the use of probiotics or antibiotics and modulating the profile of ILCs during inflammation. It would also be important to identify microbiota-derived molecules that could be involved in ILC-microbiota interactions, which could also become targets for therapeutic agents.
We welcome researchers to submit reviews, opinions and/or original research in humans and in experimental models focusing on microbiota and innate lymphoid cell biology. We hope that the results of these efforts will shape knowledge in the field and help in the development of new therapies to treat and alleviate diseases that are increasingly common among individuals.
Innate lymphoid cells (ILC) are a heterogeneous population of cells that was recently discovered in 2008 as a new group of cells present in both humans and mice and has been extensively studied over the past few years. According to the currently accepted nomenclature, these cells are divided into three main groups, depending on their pattern of expression of transcription factors and cytokines, being: group 1, including ILC1 and NK cells, mainly by the expression of T-bet and interferon (IFN)-?, resembling CD8 and Th1 cells; group 2, cells that mainly express GATA3, and cytokine IL-4, IL-5, and IL-13, similar to Th2 cells; and group 3, composed of cells expressing ROR?t that mainly produce IL-22 and IL-17, analogous to Th17 cells. Although their effector functions are close to those performed by adaptive T cells, they are considered components of the innate system because they do not recognize specific antigens – as they do not have TCR – and their activation depends mainly on the binding of cytokines and alarmins produced by other cells.
Furthermore, ILCs are mainly found along host barriers, such as skin and mucosa, and play a crucial role as the first line of defense, responding promptly with cytokine production and aiding communication between other immune and non-immune cells. Indeed, ILCs are involved in the pathogenesis of many microbiota-instructed disorders, including inflammatory bowel diseases (IBD), cancer, autoimmune diseases, allergy, asthma, obesity, and other metabolic diseases. It is already known that the commensal microbiota is extremely important for the host and, throughout its life, molds, and assists in some physiological functions, such as nutrient absorption, metabolism, and development of the immune system. However, the amount and diversity of this microbial community, as well as its derived metabolites, can vary between individuals due to several factors, including, mainly, age, diet, and metabolic/genetic disorders, and is strongly related to increased susceptibility to opportunistic infections. Considering the fact that these ILCs play a relevant role in the development of barrier immunity and a wide range of interactions with the microbiota and other cells, there are still many unanswered questions about how this newly described group of cells interferes with microbial and host communication.
The aim of this research topic is to explore and better understand the molecular insights of crosstalk between the microbiota and innate lymphoid cells on homeostasis and its impact during disease/infection. We wish to improve knowledge about the mechanisms that bacterial species or specific microbial communities have that influence the function of ILCs and control host immunity. Indeed, better identification of these groups of organisms will help to achieve microbial therapeutic targets through the use of probiotics or antibiotics and modulating the profile of ILCs during inflammation. It would also be important to identify microbiota-derived molecules that could be involved in ILC-microbiota interactions, which could also become targets for therapeutic agents.
We welcome researchers to submit reviews, opinions and/or original research in humans and in experimental models focusing on microbiota and innate lymphoid cell biology. We hope that the results of these efforts will shape knowledge in the field and help in the development of new therapies to treat and alleviate diseases that are increasingly common among individuals.
