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REVIEW article

Front. Immunol., 18 December 2025

Sec. Viral Immunology

Volume 16 - 2025 | https://doi.org/10.3389/fimmu.2025.1736658

Interferons in HIV-1 infection: mechanisms, antiviral potentials, and therapeutic challenges

  • 1Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Beijing, China
  • 2Beijing Key Laboratory for HIV/AIDS Research, Beijing Youan Hospital, Capital Medical University, Beijing, China
  • 3Second Department of Liver Disease Center, Beijing Youan Hospital, Capital Medical University, Beijing, China

Type I interferons (IFNs), particularly IFN-α, occupy a central paradox in HIV-1 infection: they provide an essential early antiviral barrier that limits initial dissemination, yet their sustained activation contributes to chronic immune activation, CD4+ T-cell dysfunction, and incomplete viral control. This duality—protective in acute infection but pathogenic during chronic disease—remains a major unresolved challenge for interferon-based therapeutic strategies in HIV-1. Recent advances in ISG functional profiling, IFN-α subtype–specific antiviral potency, and the development of targeted innate-pathway modulators (e.g., STING-selective agonists, ncRNA regulators, TLR7 activators) have renewed interest in reevaluating interferon-centered approaches. These developments make it timely to reassess whether IFN-α can be safely and effectively integrated into modern HIV-1 therapeutic concepts, particularly in early-infection windows or in rationally designed combination regimens. In this review, we synthesize current knowledge of interferon-mediated restriction mechanisms, the hierarchy of key antiviral ISGs (e.g., APOBEC3G, MX2, BST2), and HIV-1 evasion of the JAK–STAT and cGAS–STING pathways. We further analyze how dose, timing, and IFN-α subtype contribute to divergent antiviral versus inflammatory outcomes across different stages of infection. Emerging precision strategies that modulate interferon signaling without triggering systemic inflammation offer promising translational directions. Balancing antiviral efficacy with immune homeostasis will be essential for developing next-generation interferon-based interventions aimed at durable control or functional cure of HIV-1 infection.

1 Fundamental roles of interferon signaling: overview of antiviral mechanisms of type I, II, and III IFNs

Interferons (IFNs) constitute a multifunctional cytokine system that integrates innate and adaptive immunity and shapes host–virus interactions across diverse infections. To provide a conceptual foundation for understanding their relevance in HIV-1 infection, this section begins with a comparative overview of the three IFN families—type I, type II, and type III—highlighting their cellular sources, receptor distribution, and immunological consequences before addressing their clinical applications.

Type I IFNs form the most expansive IFN family and include 13 IFN-α subtypes as well as IFN-β, IFN-ϵ, IFN-κ, and IFN-ω. All signal through the widely expressed IFNAR1/IFNAR2 receptor complex, activating the JAK–STAT pathway to form the ISGF3 transcription factor and induce hundreds of ISGs (1).These ISGs—such as OAS, PKR, and MX proteins—establish a potent antiviral state, with MX2 serving as a prominent HIV-1 restriction factor by blocking capsid-dependent nuclear import (2, 3). Because IFNAR is nearly ubiquitous, type I IFNs exert broad systemic effects across hematopoietic and non-hematopoietic tissues. Defects in IFN-I production or anti–IFN autoantibodies are linked to severe viral diseases such as COVID-19, underscoring their essential antiviral function (4).However, this same breadth of activity underlies their pathogenic potential. Insights from autoimmune diseases—including systemic lupus erythematosus, rheumatoid arthritis, and primary Sjögren’s syndrome—demonstrate how chronic, dysregulated IFN-I signaling drives aberrant immune activation, antigen-presenting cell dysregulation, and T-cell dysfunction (59). These mechanisms provide a conceptual bridge to HIV-1: chronic HIV infection similarly features persistent yet sub-protective IFN-I activity that fuels immune activation, inflammatory cytokine production, and epithelial barrier perturbation.Thus, autoimmune disease is not an irrelevant detour but an instructive model of how prolonged IFN-I exposure becomes maladaptive during persistent viral infection.

Whereas type I IFNs are pleiotropic, type II IFN (IFN-γ) has a narrower functional spectrum, produced by multiple lymphocyte subsets including αβCD4+ and αβCD8+ T cells, γδ T cells, invariant natural killer T (iNKT) cells, mucosa-associated invariant T cells, and natural killer (NK) cells (10). In contrast to the broad antiviral activity of IFN-I, IFN-γ functions as a macrophage-activating factor (MAF) with a unique ability to promote clearance of intracellular pathogens—including bacteria, fungi, protozoa, and certain viruses—by macrophages, as demonstrated in studies of leprosy treatment in the mid-1980s (11). During early HIV-1 infection, IFN-γ contributes to antiviral defense; however, persistently elevated IFN-γ in chronic disease correlates with systemic immune activation and markers of disease progression rather than durable virological control. This distinction highlights that different IFN families exert phase-specific and sometimes maladaptive effects across the course of HIV infection.

Type III IFNs (IFN-λ1–4) signal through a receptor complex (IL-28Rα/IL-10Rβ) whose expression is largely restricted to epithelial cells of the gastrointestinal, respiratory, and reproductive tracts (1214), as well as select immune cells such as dendritic cells and neutrophils (1517). Although IFN-λ activates the same ISGF3 pathway as type I IFNs, its epithelial-restricted receptor distribution confers potent mucosal antiviral activity with substantially reduced systemic inflammation. This profile is particularly relevant to HIV-1, as the gastrointestinal mucosa—especially the gut-associated lymphoid tissue (GALT)—is among the earliest and most profoundly affected immune compartments, undergoing rapid memory CD4+ T-cell depletion and barrier dysfunction during acute infection (18). The biological properties of IFN-λ therefore provide a theoretical advantage for targeted antiviral activity in mucosal tissues while minimizing systemic immune activation.

After outlining endogenous IFN biology, we next address their clinical application. Recombinant IFN-α2a/α2b and IFN-β—biosynthetic analogues of leukocyte- and fibroblast-derived IFNs—are widely used in HBV (19), HCV (20), and HEV infections (21, 22). In HIV-1 and SIV models, exogenous IFN-α can reduce viral replication during early infection (23) and transiently decrease HIV-1 viremia in humans (2426). IFN-γ has also been explored therapeutically, particularly in mycobacterial infections and selected immunodeficiency disorders (2729), though its utility in HIV remains limited due to its association with chronic immune activation during established disease. Importantly, although IFN-λ signals through an epithelial-restricted receptor and generally exhibits a more favorable inflammatory and hematologic safety profile than IFN-α, its discovery and clinical development lagged far behind type I IFNs. Available hepatitis C trials show that pegylated IFN-λ can achieve antiviral responses comparable to pegylated IFN-α but with a more gradual and tissue-restricted induction of ISGs, rather than clearly superior or faster viral clearance (30). Together with the rapid displacement of interferon-based regimens by direct-acting antivirals, these features have limited the advancement of IFN-λ relative to IFN-α in regulatory approval and in HIV-focused clinical research.

Together, these comparative features of type I, II, and III IFNs establish the biological and clinical context for understanding how HIV-1 senses, responds to, evades, and potentially can be targeted through interferon-mediated pathways.

2 IFN-I signaling in HIV-1 infection: dynamics, molecular mechanisms, and immune evasion

2.1 Dynamics and biological characteristics of IFN-I signaling following HIV-1 infection

Following HIV-1 entry, the innate immune system rapidly detects viral nucleic acids and mounts a robust IFN-I response. In the early phase of infection, plasmacytoid dendritic cells (pDCs) serve as the predominant IFN-I producers, sensing viral RNA through Toll-like receptor 7/8 (TLR7/8) and activating interferon regulatory factor (IRF)–mediated pathways to secrete large amounts of IFN-α and IFN-β (31, 32). This early IFN-I burst induces restriction factors such as APOBEC3G, TRIM5α, and SAMHD1, which limit replication and dissemination (33, 34). The magnitude of this early response represents one of the host’s most critical nonspecific antiviral defenses, transiently suppressing viral spread and reducing the peak viremia in acute infection (35).

However, as infection progresses, HIV-1 evolves mechanisms that blunt IFN efficacy—by selecting IFN-resistant variants, expressing viral proteins (Vif, Vpu, Nef) that antagonize restriction factors, and suppressing innate signaling (33, 36). Clinical and animal studies demonstrate that although the acute-phase IFN-I peak correlates with reduced peak viremia, this protective effect is rarely sustained over time (37, 38).

In the chronic phase of HIV-1 infection, IFN-I levels decline substantially from their acute-phase peak but typically persist at a low-grade activation state (38, 39). This low-grade, persistent IFN-I tone is typically insufficient to control viral replication but contributes to chronic immune activation and inflammation. It is associated with sustained expression of T-cell activation markers (HLA-DR, CD38), upregulation of inhibitory receptors such as PD-1 and TIM-3, and increased susceptibility to apoptosis of bystander CD4+ T cells (3841). Abortive infection of CD4+ T cells in lymphoid tissue further amplifies inflammatory death pathways, linking persistent innate sensing and IFN-I exposure to progressive immune depletion (40, 41).

Collectively, IFN-I signaling during HIV infection exhibits a double-edged sword profile: a beneficial antiviral surge in the acute phase, contrasted with maladaptive chronic activation that perpetuates inflammation and T-cell depletion (42). Figure 1 illustrates the temporal dynamics of IFN-I levels, plasma viral load, and CD4+ T-cell counts across the course of infection, highlighting the distinct biological impacts of IFN-I in different disease stages.

Figure 1
Graph showing the dynamics of IFN-I signaling, HIV-1 RNA, and CD4+ T cells during acute and chronic HIV-1 infection. The x-axis represents time since infection in weeks, and the y-axis shows relative levels normalized. The graph illustrates variations in IFN-I signal, HIV-1 RNA, and CD4+ T cells over time, highlighting phases like the eclipse, acute peak, and chronic phase, with annotations indicating immune responses and viral mechanisms like viral escape and immune activation.

Figure 1. Dynamics of IFN-I signaling, plasma HIV-1 RNA, and CD4+ T-cell levels during acute and chronic HIV-1 infection. This schematic illustrates the temporal interplay among IFN-I responses, plasma viremia, and CD4+ T-cell dynamics after HIV-1 infection. IFN-I rises rapidly during the eclipse and acute phases (0–4 weeks), peaks with maximal viremia, and declines as adaptive immunity develops. HIV-1 RNA reaches a peak before falling to a set-point (4–8 weeks), whereas CD4+ T cells drop sharply, partially recover as IFN-I subsides, and gradually decline again during chronic infection (8w). Shaded areas mark Eclipse (0-2w), Acute Peak (2-4w), Set-point (4-8w), and Chronic (8w) phases. The overlap between IFN-I decline and CD4+ T-cell recovery is illustrative, not causal. Normalization: IFN-I and HIV-1 RNA curves are normalized to their acute-phase peaks (set = 1.0), and the CD4+ T-cell curve is normalized to the pre-infection baseline (set = 1.0). Values indicate relative, not absolute, levels. Source: Conceptual trends summarized from representative studies on acute and hyperacute HIV-1 infection and immune dynamics (4347).

While pDCs are the primary source of the acute IFN-I burst in HIV-1 infection, evidence indicates that during the chronic phase IFN-I production is maintained at low but persistent levels by other cell types. Emerging data show that tissue-resident macrophages, particularly in gut-associated lymphoid tissue and lymph-node stromal compartments, can harbor latent HIV-1 infection while expressing IFN-stimulated gene signatures and low-grade IFN production (48). Residual pDCs also contribute, though their frequency declines in chronic infection (49). The sustained IFN-I tone appears not merely a passive remnant of acute activation, but may reflect qualitative changes in innate cell programming: chronic inflammatory cues may rewire macrophage and dendritic-cell responsiveness, driving a self-amplifying feedback loop of tonic ISG induction and immune activation rather than effective viral clearance.

Building upon the dynamic features and dual-phase effects of IFN-I signaling described above, the following section delineates the molecular pathways by which HIV-1 induces IFN-I production and the subsequent immunological consequences. This mechanistic insight provides the foundation for understanding both the antiviral and immunomodulatory roles of IFN-I in HIV-1 infection.

2.2 Molecular mechanisms and immunological roles of HIV-1–induced type I interferon responses

Upon HIV-1 infection, the viral genomic RNA undergoes reverse transcription to generate cDNA, which integrates into the host genome and contributes to the establishment of a latent viral reservoir. During this process, innate immune cells detect viral nucleic acids through multiple pattern-recognition receptors (PRRs) and cytosolic nucleic-acid sensors. In pDCs, HIV-1 RNA and immune complexes are sensed primarily via endosomal TLR7/9, leading to MyD88-dependent activation of IRF7 and robust production of IFN-α subtype (32). In parallel, in myeloid dendritic cells, macrophages, and resting CD4+ T cells, HIV-1-derived cDNA is recognized by the interferon-inducible DNA sensors IFI16 and cyclic GMP–AMP synthase (cGAS), which catalyzes the synthesis of cGAMP to activate the stimulator of interferon genes (STING) pathway. Activated STING recruits and activates TANK-binding kinase 1 (TBK1), leading to phosphorylation and dimerization of IRF3, which then translocates to the nucleus to drive transcription of IFN-β and early IFN-α subtypes (5052).

In the acute phase, IFN-α is the dominant circulating IFN-I subtype and exerts both direct antiviral and immunomodulatory effects. It can inhibit HIV-1 replication at multiple stages of the viral life cycle, particularly before and immediately after integration, by inducing a spectrum of ISGs in primary CD4+ T cells and macrophages (1, 23, 53, 54) As an immunotherapeutic cytokine, IFN-α enhances innate cell function and transitions to adaptive responses by promoting CD8+ cytotoxicity and maintaining Th1 balance. Administration of IFN-α increases CD8+ T-cell activation and reduces plasma HIV RNA (55) and augments NK-cell degranulation and suppressive capacity against HIV-infected targets (56). Short-course IFN-α exposure in vivo reduces plasma HIV-1 RNA and upregulates ISG expression in peripheral blood, consistent with its role as a potent early-phase antiviral mediator (5456).

Beyond direct antiviral effects, IFN-I signaling plays a critical role in linking innate detection to adaptive immunity. Type I IFNs promote maturation of conventional dendritic cells (cDCs) (up-regulation of CD80/86, MHC I/II) and enhance their ability to cross-present cell-associated viral antigens to CD8+ T cells. In viral infections including HIV-1, this IFN-driven DC activation supports the priming of virus-specific CD8+ T-cell responses and contributes to reservoir limitation (57, 58). Incorporating this role strengthens the mechanistic link between early IFN-I responses and durable adaptive immunity.

2.3 Role of IFN-α in suppressing HIV replication and limiting viral reservoir formation

Type I IFNs, particularly IFN-α, restrict HIV-1 replication through coordinated induction of ISGs that act at distinct stages of the viral life cycle. In primary macrophages and CD4+ T cells, IFN-α reduces the accumulation of HIV-1 cDNA and suppresses early replication through proteasome-dependent mechanisms (53), In resting CD4+ T cells, IFN-α potently enhances the antiviral activity of APOBEC3G, promoting G→A hypermutation in nascent viral DNA and thereby limiting residual replication within cells that contribute to the latent reservoir (59). In vivo studies further demonstrate that IFN-α treatment can lower HIV-1 viral load while upregulating the expression of restriction factors such as APOBEC3G/3F and BST-2/tetherin (54).

IFN-α-induced ISGs restrict HIV-1 replication at multiple checkpoints throughout the viral life cycle. (1) During viral entry and fusion, IFITM3 is strongly up-regulated and localizes to plasma and endosomal membranes, altering membrane fluidity and blocking fusion between viral and host membranes, thereby reducing entry efficiency (60). (2) During reverse transcription, SAMHD1 depletes intracellular dNTP pools in resting CD4+ T cells and macrophages, while CMPK2 maintains nucleotide balance under interferon signaling; together, these effects limit viral cDNA synthesis and halt reverse transcription (61, 62). (3) In the nuclear import or pre-integration stage, MX2 (MxB) acts post-reverse transcription but prior to integration by localizing to the nuclear envelope and interacting with nucleoporins (NUP214, TNPO1) to block nuclear entry of the pre-integration complex (63). In contrast, TRIM5α acts at an earlier post-entry step by recognizing the HIV-1 capsid, promoting its proteasomal degradation and preventing reverse transcription (64). (4) Following integration, APOBEC3G and APOBEC3F are packaged into virions, where they introduce G→A hypermutations that corrupt proviral genomes and reduce replication competence (59). (5) During virion assembly, ISG15 conjugates to viral and host budding factors such as Gag, hindering membrane fission and virion release, thereby reducing HIV-1 infectivity (65). (6) At the budding and release stage, BST-2/tetherin, highly expressed on activated CD4+ T cells and in lymphoid/mucosal tissues, anchors nascent virions at the cell surface, physically preventing virus release and cell-to-cell dissemination (66). Recent multi-omics analyses continue to expand the catalogue of cell-intrinsic effectors that contribute to IFN-I–mediated restriction of HIV-1 in primary CD4+ T cells (67). Table 1 summarizes the major ISGs and their anti-HIV-1 mechanisms.

Table 1
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Table 1. Major IFN-α–induced ISGs and their mechanisms of HIV-1 restriction.

Collectively, these IFN-α-induced antiviral mechanisms act in a temporally ordered cascade—from viral entry to release—to minimize productive infection and constrain the establishment of the latent reservoir. Despite the robust IFN-induced blockade observed in vitro, clinical efficacy in vivo remains limited, reflecting coordinated viral countermeasures (e.g., Vpu, Nef, capsid shielding), tissue-level constraints, and immune exhaustion driven by chronic interferon exposure. Together, these processes uncouple ISG induction from durable viral control in patients.

2.4 HIV immune evasion: targeting interferon signaling

HIV-1 employs temporally ordered immune-evasion strategies that align with distinct stages of its replication cycle, enabling the virus to circumvent IFN-I sensing, restrictor induction, and downstream effector pathways.

2.4 .1Early phase: capsid-based evasion of nucleic-acid sensing

Immediately after entry, the HIV-1 capsid recruits host cofactors such as cyclophilin A and CPSF6 to stabilize its lattice and shield reverse-transcribed DNA from cytosolic sensors including cGAS and IFI16 (69).This capsid-cofactor “cloak” constitutes the earliest evasion layer, preventing STING–TBK1–IRF3 activation and blunting the initial IFN-I burst.

2.4.2 Reverse-transcription stage: antagonism of intrinsic restriction factors

During reverse transcription, HIV-1 counters key ISGs: Vif mediates APOBEC3G/3F degradation, and Vpr modulates nucleotide metabolism to reduce SAMHD1-mediated restriction (33, 54, 62). These steps secure efficient synthesis of viral cDNA and formation of the pre-integration complex.

2.4.3 Integration and early post-integration phase: chromatin remodeling and suppression of IFN-responsive loci

Following integration, HIV-1 shapes a chromatin environment that favors proviral persistence. Viral proteins can recruit HDACs and promote repressive marks such as H3K27me3 at interferon-regulated promoters (70, 71), while chronic IFN exposure further reinforces a transcriptionally restrained, latency-compatible state (72, 73). These epigenetic changes weaken IFN-inducible antiviral programs and stabilize the reservoir.

2.4.4 Late phase: evasion of ISG-mediated suppression of virion release and infectivity

At the assembly and release stages, HIV-1 directly antagonizes ISG effector functions: Vpu counteracts BST-2/tetherin to permit virion release (74), and Nef inhibits SERINC5 to enhance the infectivity of progeny particles (75). These mechanisms operate downstream of reverse transcription and ensure productive viral egress even in an ISG-rich environment.

2.4.5 Cross-phase regulation: epigenetic and ncRNA-mediated tuning of interferon pathways

Beyond stage-specific evasion events, HIV-1 also exploits cross-phase regulatory mechanisms that persist throughout the viral life cycle. Epigenetic modifications play a central role in this process. Histone modifications, particularly HDAC recruitment and PRC2-mediated H3K27 trimethylation, establish a transcriptionally repressive chromatin environment at the HIV-1 long terminal repeat (LTR) and interferon-responsive genes, thereby favoring latency rather than effective immune clearance (7678). These changes are driven both by viral proteins and by prolonged exposure to inflammatory and interferon-rich conditions. Long non-coding RNAs further modulate chromatin structure and gene expression, adding an additional regulatory layer to innate immune programs (79).

In parallel, microRNAs regulate interferon signaling at the post-transcriptional level. Among them, miR-146a functions as a key negative-feedback regulator of innate immunity. HIV-1 infection induces miR-146a expression, which targets IRAK1 and TRAF6, reduces NF-κB activation, and attenuates interferon-stimulated gene expression (80, 81). Elevated miR-146a levels in chronic HIV-1 infection correlate with immune cell exhaustion and impaired antiviral responses (81). Together, these epigenetic and ncRNA-mediated mechanisms do not operate at a single replication stage, but provide sustained suppression of interferon pathways across acute and chronic phases of infection, thereby facilitating immune evasion and viral persistence.

Together, these analyses illustrate that IFN-I–driven antiviral restriction and HIV-1 immune evasion do not culminate in a unilateral “victory,” but instead establish a dynamic and pathologic host–virus equilibrium. IFN-I responses dominate briefly during acute infection, limiting early viral dissemination, yet HIV-1 rapidly acquires multilayered escape strategies that enable persistent replication and reservoir formation. Conversely, these escape adaptations incur fitness constraints on the virus, while the host maintains a chronically activated but sub-protective IFN-I milieu that restricts viral expansion without achieving clearance. This reciprocal adjustment between antiviral pressure and viral countermeasures forms a long-lasting, inflammation-prone steady state that underlies the clinical transition from acute containment to chronic immune dysregulation.

3 IFN-α in HIV-1 therapy: antiviral potential and immunological risks

3.1 Subtype specificity and clinical rationale for IFN-α2b

Although all 13 IFN-α subtypes signal through the shared IFNAR1/2-JAK-STAT/ISGF3 axis, they exhibit distinct biological profiles in antiviral potency and immune modulation. Comparative analyses consistently identify IFN-α6, IFN-α8, and IFN-α14 as the most potent subtypes against HIV-1, markedly suppressing viral replication in humanized mice and ex vivo primary-cell systems, whereas IFN-α1 and IFN-α4 show weak activity. These differences are not absolute: their rank order varies across models, and dose–response dynamics strongly influence outcomes—at high concentrations, subtype disparities diminish, indicating that both intrinsic affinity and ligand exposure jointly shape ISG induction and antiviral efficacy (8284).

Subtype-specific immune regulation further distinguishes their functional profiles. IFN-α14 and IFN-α8 promote NK- and CD8+ T-cell degranulation but induce less inflammatory cytokine release, whereas others preferentially trigger broader ISG and cytokine cascades (84). However, direct evidence that these subtypes cause greater systemic toxicity in patients is currently limited. Most safety data are derived from Peg-IFN-α2–based trials, and whether highly potent subtypes intrinsically confer a poorer tolerability profile remains an open clinical question rather than an established fact.

Despite its moderate antiviral potency, IFN-α2b remains the clinical standard due to its well-established pharmacokinetics, manufacturing stability, and tolerability. Pegylation extends its plasma half-life, smooths exposure peaks, and enables once-weekly administration, providing a controlled immunostimulatory window validated in HBV/HCV and subsequently adapted to HIV clinical research. While next-generation formulations may explore potent subtypes such as IFN-α14, Peg-IFN-α2b currently offers the most reliable balance of antiviral efficacy, safety, and translational feasibility.

3.2 Clinical outcomes and stage-dependent effects of IFN-α therapy in HIV-1 infection

Over four decades, multiple clinical and translational studies have evaluated IFN-α as both a stand-alone antiviral and an adjunct to ART in HIV-1 infection. Table 2 summarizes representative trials spanning the pre-ART, early-ART, and modern-ART eras. These investigations reveal a consistent pattern: short-term IFN-α exposure transiently reduces plasma viremia and integrated HIV-1 DNA, whereas prolonged administration yields diminishing returns accompanied by immune activation and tolerability issues.

Table 2
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Table 2. Clinical studies of IFN-α in patients with HIV infection.

During acute or early infection stages, initial clinical trials have shown that parenteral administration of IFN-α2b can effectively inhibit viral replication before the establishment of viral reservoirs, leading to temporary reductions in viral load and a delayed viral rebound after treatment cessation. However, in chronically infected individuals who have achieved virologic suppression under ART, pegylated IFN-α2a/α2b used as add-on therapy produces only modest reservoir perturbation, including limited reductions in integrated HIV-1 DNA and increased innate and cytotoxic effector activity (26, 54, 89). Importantly, available analytical treatment interruption studies indicate that these changes do not translate into consistent delays in viral rebound or durable post-treatment control, and rebound kinetics correlate more strongly with the size and integrity of the latent reservoir than with prior interferon exposure (8991). Together, these data indicate that the therapeutic window of IFN-α is phase-dependent: benefits, when present, are most apparent before reservoir consolidation rather than during established chronic infection.

These findings demonstrate that IFN-α can transiently suppress plasma viremia and reduce integrated HIV-1 DNA, especially when used early in infection or as a pegylated adjunct to ART. However, the limited durability of viral control and the frequent occurrence of inflammatory side effects underscore the narrow therapeutic window of IFN-α. The following section examines the immunological consequences of sustained IFN-α signaling, including chronic immune activation, T-cell exhaustion, and their implications for long-term HIV management.

3.3 Immunological risks and potential harms of IFN-α in chronic HIV-1 infection

The efficacy of IFN-α in individuals with chronic HIV-1 infection remains controversial. In untreated chronic infection, plasma IFN-α concentrations strongly correlate with plasma HIV-1 RNA levels and markers of immune activation, while inversely correlating with CD4+ T-cell counts, suggesting that persistent IFN-α signaling contributes directly to systemic immune activation (39). Mechanistically, IFN-α downregulates IL-7 receptor α (CD127) expression on CD4+ and CD8+ T cells, in part through sustained JAK–STAT signaling and SOCS induction, thereby impairing IL-7-driven homeostatic proliferation and T-cell recovery (92, 93).

Clinical observations reveal highly variable CD4+ T-cell dynamics under IFN-α treatment. In some cohorts, individuals with higher baseline CD4+ counts or early-stage disease maintained or exhibited modest, transient increases in CD4+ T cells; however, these gains were short-lived (55). The magnitude of CD4+ response appears to depend on baseline immune status—patients initiating therapy at higher CD4+ levels respond more favorably, whereas those with advanced disease or immune exhaustion show minimal recovery (94, 95). Conversely, individuals with advanced HIV or HIV/HCV co-infection often experience negligible or even declining CD4+ counts (96).

The ability of IFN-α to reduce viral load also varies. While some studies have demonstrated reductions in HIV viral load with IFN-α therapy, not all patients respond similarly. Its impact on the viral reservoir appears limited; one study reported poor efficacy in reducing HIV DNA and no significant restriction of the viral reservoir (97). Multiple factors influence treatment outcomes, with a dose-dependent effect observed—higher IFN-α doses are associated with greater reductions in viral load and virological markers but also with increased adverse events and treatment discontinuations (98, 99). Furthermore, the virological and immunological effects of IFN-α are generally transient, with rebound occurring after treatment cessation, and tolerability issues limit long-term use (55, 100).

In summary, the use of IFN-α during chronic HIV-1 infection has not demonstrated sustained clinical benefits and may instead induce or exacerbate chronic immune activation, potentially hindering long-term immune reconstitution. Its application in this setting should therefore be carefully evaluated, taking into account the patient’s immune status, disease stage, and treatment tolerability.

4 Emerging strategies and combination immunotherapies

4.1 STING agonists

Interferon-based therapy faces a central dilemma: preserving antiviral sensing without provoking systemic inflammation. STING agonists address this by activating cell-intrinsic innate immunity at tissue sites rather than raising circulating interferon. In acute infection, STING activation enhances viral sensing and type I interferon production, limiting early replication. HIV-1 is detected through the cGAS–STING axis, which initiates interferon signaling and antiviral programs (51, 52). In chronic HIV infection, however, plasma viremia is largely controlled by ART, and therapy shifts from suppressing replication to disrupting viral persistence. Accordingly, STING agonists are not intended as direct antivirals. Instead, they are used to perturb the latent reservoir by (i) promoting proviral transcription and chromatin changes that increase “visibility” of infected cells, and (ii) enhancing innate sensing and antigen presentation in lymphoid tissues to facilitate immune clearance. Sustained systemic STING activation is neither necessary nor desirable, as excessive interferon can reproduce immune dysfunction. Current strategies therefore emphasize transient or localized activation to achieve reservoir-directed effects while limiting inflammation. Intercellular transfer of cGAMP can further amplify STING signaling within tissue microenvironments, supporting this localized approach (101).

4.2 ncRNA-targeted therapy

The regulatory role of ncRNAs in IFN signaling offers novel therapeutic opportunities. Type I IFN-induced lncRNA ISR2 can enhance antiviral responses when delivered via nanoparticle systems (102), miR-146a—an immunosuppressive miRNA upregulated during HIV infection—can be inhibited by anti-miR-146a, thereby augmenting IFN-mediated T-cell activation (103). Importantly, in this context, “T-cell activation” refers to restoration of antiviral competence (e.g., cytotoxic activity and responsiveness to antigenic stimulation) rather than nonspecific inflammatory activation, which is already excessive in chronic HIV-1 infection. In chronic disease, persistent miR-146a expression may blunt antiviral signaling as part of a negative-feedback program restraining IFN and NF-κB pathways; although anti-inflammatory in principle, this may also contribute to immune dysfunction and incomplete viral control when sustained. ncRNA-based therapy remains conceptual rather than clinical: efficient and cell-specific delivery to CD4+ T cells or macrophages is still a major obstacle. Technical barriers include vector safety, off-target effects, and metabolic stability (104, 105).Incorporating ncRNA regulation into IFN-pathway modulation could eventually complement latency-reversing or immune-boosting strategies, but requires significant preclinical validation.

4.3 TLR7 agonists

TLR7 agonists, represented by vesatolimod (GS-9620), selectively activate innate immune signaling pathways and induce type I IFN responses. In HIV-infected individuals receiving suppressive ART, vesatolimod has demonstrated a favorable safety profile, eliciting transient increases in ISGs, plasma cytokines, and activation markers on peripheral immune cells without causing sustained inflammation or viral rebound (106). Notably, this contrasts with pegylated IFN-α therapy, in which continuous systemic exposure results in prolonged interferon signaling and cumulative toxicity. In comparison, TLR7 agonists induce short, intermittent interferon “pulses” that more closely resemble physiological innate immune activation rather than sustained pharmacologic exposure.In preclinical nonhuman primate models, TLR7-driven immune stimulation in combination with broadly neutralizing antibodies (bNAbs) significantly delayed viral rebound following ART interruption (107). Parallel studies have shown that combining therapeutic vaccination (Ad26/MVA ± gp140) with intermittent TLR7 administration enhances virologic control and strengthens antiviral T-cell responses, particularly when ART is initiated during acute infection (108). Current translational research focuses on optimizing the timing and sequence of TLR7 agonist administration relative to ART and immunotherapeutic interventions—for instance, priming with bNAbs or therapeutic vaccines before innate immune activation—to maximize efficacy while minimizing immune hyperactivation. In summary, TLR7 agonists targeting the IFN signaling pathway hold considerable promise in HIV cure research and warrant further mechanistic refinement and preclinical evaluation.

5 Conclusion

Interferons represent a pivotal bridge between innate and adaptive immunity, exerting potent antiviral and immunomodulatory effects. Among them, type I IFN-α remains the most extensively characterized and therapeutically explored in HIV-1 infection. Evidence from animal models and human trials indicates that early IFN-α administration can restrict viral replication and reservoir establishment. However, during chronic infection, prolonged IFN-α signaling fuels immune activation and T-cell exhaustion. Future approaches must adopt decoupling as a governing principle—preserving antiviral efficacy while disengaging pathways that fuel pathological immune activation.

The clinical limitations of IFN-α therapy in established infection reflect several fundamental barriers, including cumulative toxicity from sustained exposure, reinforcement of immune exhaustion, failure to eradicate the latent reservoir, and viral antagonism of interferon signaling. Collectively, these mechanisms explain why robust induction of interferon-stimulated genes has not translated into durable control in vivo. Importantly, these constraints do not negate the therapeutic potential of interferons but redefine the context in which they may be effective.

Recent advances indicate that interferon activity can be repositioned rather than abandoned. Therapeutic strategies that confine interferon exposure to the acute phase of HIV infection, prior to reservoir establishment, may exploit antiviral function when it is biologically most effective and least immunopathogenic. In established infection, interventions that primarily target innate pathways—such as STING agonists, TLR7 agonists, and selected ncRNA-based strategies—are being developed not simply to further amplify cytokine output, but to better control the spatial and temporal dimensions of interferon signaling. By concentrating antiviral signals in relevant tissues and limiting their duration, these approaches aim to reshape the local immune microenvironment while reducing the risk of chronic systemic activation. In this sense, conditioning innate immunity may provide an important foundation for rational combination regimens and enhance the effectiveness of downstream adaptive interventions.

Interferons in HIV should no longer be regarded merely as antiviral cytokines, but as master regulators of immune organization. The future of HIV cure research depends less on intensifying interferon exposure than on programming its deployment—transforming a double-edged pathway into a calibrated therapeutic tool capable of durable impact.

Author contributions

LZ: Investigation, Data curation, Writing – review & editing, Resources, Visualization, Writing – original draft. JJ: Data curation, Writing – review & editing. JX: Data curation, Writing – review & editing. FW: Writing – review & editing, Resources. JY: Writing – review & editing, Data curation. YL: Writing – review & editing, Conceptualization, Data curation. YZ: Data curation, Methodology, Writing – review & editing. HW: Supervision, Writing – review & editing. BS: Supervision, Writing – review & editing. XL: Supervision, Writing – review & editing, Methodology. TZ: Writing – review & editing, Supervision, Formal Analysis.

Funding

The author(s) declared that financial support was received for work and/or its publication. This work was supported by the Beijing Hospital Management Center Phase III “Sailing” Program: Clinical Technology Innovation Project (ZLRK202532 to TZ), the National Science and Technology Major Project for the Prevention and Control of Emerging and Major Infectious Diseases (2025ZD01905400 to TZ; 2025ZD01905404 to XL), the High-level Public Health Technical Personnel Construction Project (2022-1-007 to TZ; 2023-02-21 to XL), and the Beijing Key Laboratory for HIV/AIDS Research (BZ0089). No commercial funding was involved in this work.

Conflict of interest

The author(s) declared that this work 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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References

1. Schoggins JW, Wilson SJ, Panis M, Murphy MY, Jones CT, Bieniasz P, et al. A diverse range of gene products are effectors of the type I interferon antiviral response. Nature. (2011) 472:481–5. doi: 10.1038/nature09907

PubMed Abstract | Crossref Full Text | Google Scholar

2. Kane M, Yadav SS, Bitzegeio J, Kutluay SB, Zang T, Wilson SJ, et al. MX2 is an interferon-induced inhibitor of HIV-1 infection. Nature. (2013) 502:563–6. doi: 10.1038/nature12653

PubMed Abstract | Crossref Full Text | Google Scholar

3. Goujon C, Moncorge O, Bauby H, Doyle T, Ward CC, Schaller T, et al. Human MX2 is an interferon-induced post-entry inhibitor of HIV-1 infection. Nature. (2013) 502:559–62. doi: 10.1038/nature12542

PubMed Abstract | Crossref Full Text | Google Scholar

4. Casanova JL and Abel L. From rare disorders of immunity to common determinants of infection: Following the mechanistic thread. Cell. (2022) 185:3086–103. doi: 10.1016/j.cell.2022.07.004

PubMed Abstract | Crossref Full Text | Google Scholar

5. Der E, Suryawanshi H, Morozov P, Kustagi M, Goilav B, Ranabothu S, et al. Tubular cell and keratinocyte single-cell transcriptomics applied to lupus nephritis reveal type I IFN and fibrosis relevant pathways. Nat Immunol. (2019) 20:915–27. doi: 10.1038/s41590-019-0386-1

PubMed Abstract | Crossref Full Text | Google Scholar

6. Crow MK. Type I interferon in the pathogenesis of lupus. J Immunol. (2014) 192:5459–68. doi: 10.4049/jimmunol.1002795

PubMed Abstract | Crossref Full Text | Google Scholar

7. Oke V, Gunnarsson I, Dorschner J, Eketjall S, Zickert A, Niewold TB, et al. High levels of circulating interferons type I, type II and type III associate with distinct clinical features of active systemic lupus erythematosus. Arthritis Res Ther. (2019) 21:107. doi: 10.1186/s13075-019-1878-y

PubMed Abstract | Crossref Full Text | Google Scholar

8. Lubbers J, Brink M, van de Stadt LA, Vosslamber S, Wesseling JG, van Schaardenburg D, et al. The type I IFN signature as a biomarker of preclinical rheumatoid arthritis. Ann Rheum Dis. (2013) 72:776–80. doi: 10.1136/annrheumdis-2012-202753

PubMed Abstract | Crossref Full Text | Google Scholar

9. Ha YJ, Choi YS, Kang EH, Chung JH, Cha S, Song YW, et al. Increased expression of interferon-lambda in minor salivary glands of patients with primary Sjogren’s syndrome and its synergic effect with interferon-alpha on salivary gland epithelial cells. Clin Exp Rheumatol. (2018) 36 Suppl 112:31–40.

Google Scholar

10. Yang R, Mele F, Worley L, Langlais D, Rosain J, Benhsaien I, et al. Human T-bet governs innate and innate-like adaptive IFN-gamma immunity against mycobacteria. Cell. (2020) 183:1826–47 e31.

PubMed Abstract | Google Scholar

11. Nathan CF, Kaplan G, Levis WR, Nusrat A, Witmer MD, Sherwin SA, et al. Local and systemic effects of intradermal recombinant interferon-gamma in patients with lepromatous leprosy. N Engl J Med. (1986) 315:6–15. doi: 10.1056/NEJM198607033150102

PubMed Abstract | Crossref Full Text | Google Scholar

12. Mordstein M, Neugebauer E, Ditt V, Jessen B, Rieger T, Falcone V, et al. Lambda interferon renders epithelial cells of the respiratory and gastrointestinal tracts resistant to viral infections. J Virol. (2010) 84:5670–7. doi: 10.1128/JVI.00272-10

PubMed Abstract | Crossref Full Text | Google Scholar

13. Sommereyns C, Paul S, Staeheli P, and Michiels T. IFN-lambda (IFN-lambda) is expressed in a tissue-dependent fashion and primarily acts on epithelial cells in vivo. PloS Pathog. (2008) 4:e1000017. doi: 10.1371/journal.ppat.1000017

PubMed Abstract | Crossref Full Text | Google Scholar

14. Hernandez PP, Mahlakoiv T, Yang I, Schwierzeck V, Nguyen N, Guendel F, et al. Interferon-lambda and interleukin 22 act synergistically for the induction of interferon-stimulated genes and control of rotavirus infection. Nat Immunol. (2015) 16:698–707.

PubMed Abstract | Google Scholar

15. Blazek K, Eames HL, Weiss M, Byrne AJ, Perocheau D, Pease JE, et al. IFN-lambda resolves inflammation via suppression of neutrophil infiltration and IL-1beta production. J Exp Med. (2015) 212:845–53. doi: 10.1084/jem.20140995

PubMed Abstract | Crossref Full Text | Google Scholar

16. Koltsida O, Hausding M, Stavropoulos A, Koch S, Tzelepis G, Ubel C, et al. IL-28A (IFN-lambda2) modulates lung DC function to promote Th1 immune skewing and suppress allergic airway disease. EMBO Mol Med. (2011) 3:348–61. doi: 10.1002/emmm.201100142

PubMed Abstract | Crossref Full Text | Google Scholar

17. Espinosa V, Dutta O, McElrath C, Du P, Chang YJ, Cicciarelli B, et al. Type III interferon is a critical regulator of innate antifungal immunity. Sci Immunol. (2017) 2. doi: 10.1126/sciimmunol.aan5357

PubMed Abstract | Crossref Full Text | Google Scholar

18. Brenchley JM, Schacker TW, Ruff LE, Price DA, Taylor JH, Beilman GJ, et al. CD4+ T cell depletion during all stages of HIV disease occurs predominantly in the gastrointestinal tract. J Exp Med. (2004) 200:749–59. doi: 10.1084/jem.20040874

PubMed Abstract | Crossref Full Text | Google Scholar

19. Terrault NA, Lok ASF, McMahon BJ, Chang KM, Hwang JP, Jonas MM, et al. Update on prevention, diagnosis, and treatment of chronic hepatitis B: AASLD 2018 hepatitis B guidance. Hepatology. (2018) 67:1560–99. doi: 10.1002/hep.29800

PubMed Abstract | Crossref Full Text | Google Scholar

20. World Gastroenterology Organisation. Hepatitis C: Diagnosis, Management, and Prevention – Global Guidelines. (Munich: World Gastroenterology Organisation). (2017).

Google Scholar

21. Li SF, Gong MJ, Zhao FR, Shao JJ, Xie YL, Zhang YG, et al. Type I interferons: distinct biological activities and current applications for viral infection. Cell Physiol Biochem. (2018) 51:2377–96. doi: 10.1159/000495897

PubMed Abstract | Crossref Full Text | Google Scholar

22. Todt D, Francois C, Anggakusuma, Behrendt P, Engelmann M, Knegendorf L, et al. Antiviral activities of different interferon types and subtypes against hepatitis E virus replication. Antimicrob Agents Chemother. (2016) 60:2132–9. doi: 10.1128/AAC.02427-15

PubMed Abstract | Crossref Full Text | Google Scholar

23. Kane M, Zang TM, Rihn SJ, Zhang F, Kueck T, Alim M, et al. Identification of interferon-stimulated genes with antiretroviral activity. Cell Host Microbe. (2016) 20:392–405. doi: 10.1016/j.chom.2016.08.005

PubMed Abstract | Crossref Full Text | Google Scholar

24. Sun H, Buzon MJ, Shaw A, Berg RK, Yu XG, Ferrando-Martinez S, et al. Hepatitis C therapy with interferon-alpha and ribavirin reduces CD4 T-cell-associated HIV-1 DNA in HIV-1/hepatitis C virus-coinfected patients. J Infect Dis. (2014) 209:1315–20. doi: 10.1093/infdis/jit628

PubMed Abstract | Crossref Full Text | Google Scholar

25. Emilie D, Burgard M, Lascoux-Combe C, Laughlin M, Krzysiek R, Pignon C, et al. Early control of HIV replication in primary HIV-1 infection treated with antiretroviral drugs and pegylated IFN alpha: results from the Primoferon A (ANRS 086) Study. AIDS. (2001) 15:1435–7. doi: 10.1097/00002030-200107270-00014

PubMed Abstract | Crossref Full Text | Google Scholar

26. Asmuth DM, Murphy RL, Rosenkranz SL, Lertora JJ, Kottilil S, Cramer Y, et al. Safety, tolerability, and mechanisms of antiretroviral activity of pegylated interferon Alfa-2a in HIV-1-monoinfected participants: a phase II clinical trial. J Infect Dis. (2010) 201:1686–96. doi: 10.1086/652420

PubMed Abstract | Crossref Full Text | Google Scholar

27. Gollob JA, Rathmell WK, Richmond TM, Marino CB, Miller EK, Grigson G, et al. Phase II trial of sorafenib plus interferon alfa-2b as first- or second-line therapy in patients with metastatic renal cell cancer. J Clin Oncol. (2007) 25:3288–95. doi: 10.1200/JCO.2007.10.8613

PubMed Abstract | Crossref Full Text | Google Scholar

28. Assanto GM, Riemma C, Malaspina F, Perrone S, De Luca ML, Annechini G, et al. Long-term treatment of hairy cell leukemia patients with interferon: clinical and molecular aspects. Blood. (2020) 136:37. doi: 10.1182/blood-2020-136660

Crossref Full Text | Google Scholar

29. Webster JA, Robinson TM, Blackford AL, Warlick E, Ferguson A, Borrello I, et al. A randomized, phase II trial of adjuvant immunotherapy with durable TKI-free survival in patients with chronic phase CML. Leuk Res. (2021) 111:106737. doi: 10.1016/j.leukres.2021.106737

PubMed Abstract | Crossref Full Text | Google Scholar

30. Chan HLY, Ahn SH, Chang TT, Peng CY, Wong D, Coffin CS, et al. Peginterferon lambda for the treatment of HBeAg-positive chronic hepatitis B: A randomized phase 2b study (LIRA-B). J Hepatol. (2016) 64:1011–9. doi: 10.1016/j.jhep.2015.12.018

PubMed Abstract | Crossref Full Text | Google Scholar

31. Cisse B, Caton ML, Lehner M, Maeda T, Scheu S, Locksley R, et al. Transcription factor E2–2 is an essential and specific regulator of plasmacytoid dendritic cell development. Cell. (2008) 135:37–48. doi: 10.1016/j.cell.2008.09.016

PubMed Abstract | Crossref Full Text | Google Scholar

32. Fitzgerald-Bocarsly P and Jacobs ES. Plasmacytoid dendritic cells in HIV infection: striking a delicate balance. J Leukoc Biol. (2010) 87:609–20. doi: 10.1189/jlb.0909635

PubMed Abstract | Crossref Full Text | Google Scholar

33. Sheehy AM, Gaddis NC, Choi JD, and Malim MH. Isolation of a human gene that inhibits HIV-1 infection and is suppressed by the viral Vif protein. Nature. (2002) 418:646–50. doi: 10.1038/nature00939

PubMed Abstract | Crossref Full Text | Google Scholar

34. Laguette N, Sobhian B, Casartelli N, Ringeard M, Chable-Bessia C, Segeral E, et al. SAMHD1 is the dendritic- and myeloid-cell-specific HIV-1 restriction factor counteracted by Vpx. Nature. (2011) 474:654–7. doi: 10.1038/nature10117

PubMed Abstract | Crossref Full Text | Google Scholar

35. Stacey AR, Norris PJ, Qin L, Haygreen EA, Taylor E, Heitman J, et al. Induction of a striking systemic cytokine cascade prior to peak viremia in acute human immunodeficiency virus type 1 infection, in contrast to more modest and delayed responses in acute hepatitis B and C virus infections. J Virol. (2009) 83:3719–33. doi: 10.1128/JVI.01844-08

PubMed Abstract | Crossref Full Text | Google Scholar

36. Foster TL, Wilson H, Iyer SS, Coss K, Doores K, Smith S, et al. Resistance of transmitted founder HIV-1 to IFITM-mediated restriction. Cell Host Microbe. (2016) 20:429–42. doi: 10.1016/j.chom.2016.08.006

PubMed Abstract | Crossref Full Text | Google Scholar

37. Sandler NG, Bosinger SE, Estes JD, Zhu RT, Tharp GK, Boritz E, et al. Type I interferon responses in rhesus macaques prevent SIV infection and slow disease progression. Nature. (2014) 511:601–5. doi: 10.1038/nature13554

PubMed Abstract | Crossref Full Text | Google Scholar

38. Zhen A, Rezek V, Youn C, Lam B, Chang N, Rick J, et al. Targeting type I interferon-mediated activation restores immune function in chronic HIV infection. J Clin Invest. (2017) 127:260–8. doi: 10.1172/JCI89488

PubMed Abstract | Crossref Full Text | Google Scholar

39. Hardy GA, Sieg S, Rodriguez B, Anthony D, Asaad R, Jiang W, et al. Interferon-alpha is the primary plasma type-I IFN in HIV-1 infection and correlates with immune activation and disease markers. PloS One. (2013) 8:e56527.

PubMed Abstract | Google Scholar

40. Finkel TH, Tudor-Williams G, Banda NK, Cotton MF, Curiel T, Monks C, et al. Apoptosis occurs predominantly in bystander cells and not in productively infected cells of HIV- and SIV-infected lymph nodes. Nat Med. (1995) 1:129–34. doi: 10.1038/nm0295-129

PubMed Abstract | Crossref Full Text | Google Scholar

41. Doitsh G, Cavrois M, Lassen KG, Zepeda O, Yang Z, Santiago ML, et al. Abortive HIV infection mediates CD4 T cell depletion and inflammation in human lymphoid tissue. Cell. (2010) 143:789–801. doi: 10.1016/j.cell.2010.11.001

PubMed Abstract | Crossref Full Text | Google Scholar

42. Herbeuval JP, Nilsson J, Boasso A, Hardy AW, Kruhlak MJ, Anderson SA, et al. Differential expression of IFN-alpha and TRAIL/DR5 in lymphoid tissue of progressor versus nonprogressor HIV-1-infected patients. Proc Natl Acad Sci U S A. (2006) 103:7000–5. doi: 10.1073/pnas.0600363103

PubMed Abstract | Crossref Full Text | Google Scholar

43. McMichael AJ, Borrow P, Tomaras GD, Goonetilleke N, and Haynes BF. The immune response during acute HIV-1 infection: clues for vaccine development. Nat Rev Immunol. (2010) 10:11–23. doi: 10.1038/nri2674

PubMed Abstract | Crossref Full Text | Google Scholar

44. Borrow P. Innate immunity in acute HIV-1 infection. Curr Opin HIV AIDS. (2011) 6:353–63. doi: 10.1097/COH.0b013e3283495996

PubMed Abstract | Crossref Full Text | Google Scholar

45. Kazer SW, Aicher TP, Muema DM, Carroll SL, Ordovas-Montanes J, Miao VN, et al. Integrated single-cell analysis of multicellular immune dynamics during hyperacute HIV-1 infection. Nat Med. (2020) 26:511–8. doi: 10.1038/s41591-020-0799-2

PubMed Abstract | Crossref Full Text | Google Scholar

46. Cheret A. Acute HIV-1 infection: paradigm and singularity. Viruses. (2025) 17. doi: 10.3390/v17030366

PubMed Abstract | Crossref Full Text | Google Scholar

47. Ndhlovu ZM, Kamya P, Mewalal N, Kloverpris HN, Nkosi T, Pretorius K, et al. Magnitude and kinetics of CD8+ T cell activation during hyperacute HIV infection impact viral set point. Immunity. (2015) 43:591–604. doi: 10.1016/j.immuni.2015.08.012

PubMed Abstract | Crossref Full Text | Google Scholar

48. Rojas M, Luz-Crawford P, Soto-Rifo R, Reyes-Cerpa S, and Toro-Ascuy D. The landscape of IFN/ISG signaling in HIV-1-infected macrophages and its possible role in the HIV-1 latency. Cells. (2021) 10. doi: 10.3390/cells10092378

PubMed Abstract | Crossref Full Text | Google Scholar

49. Sabado RL, O’Brien M, Subedi A, Qin L, Hu N, Taylor E, et al. Evidence of dysregulation of dendritic cells in primary HIV infection. Blood. (2010) 116:3839–52. doi: 10.1182/blood-2010-03-273763

PubMed Abstract | Crossref Full Text | Google Scholar

50. Ma F, Li B, Liu SY, Iyer SS, Yu Y, Wu A, et al. Positive feedback regulation of type I IFN production by the IFN-inducible DNA sensor cGAS. J Immunol. (2015) 194:1545–54. doi: 10.4049/jimmunol.1402066

PubMed Abstract | Crossref Full Text | Google Scholar

51. Gao D, Wu J, Wu YT, Du F, Aroh C, Yan N, et al. Cyclic GMP-AMP synthase is an innate immune sensor of HIV and other retroviruses. Science. (2013) 341:903–6. doi: 10.1126/science.1240933

PubMed Abstract | Crossref Full Text | Google Scholar

52. Jakobsen MR, Bak RO, Andersen A, Berg RK, Jensen SB, Tengchuan J, et al. IFI16 senses DNA forms of the lentiviral replication cycle and controls HIV-1 replication. Proc Natl Acad Sci U S A. (2013) 110:E4571–80. doi: 10.1073/pnas.1311669110

PubMed Abstract | Crossref Full Text | Google Scholar

53. Goujon C and Malim MH. Characterization of the alpha interferon-induced postentry block to HIV-1 infection in primary human macrophages and T cells. J Virol. (2010) 84:9254–66. doi: 10.1128/JVI.00854-10

PubMed Abstract | Crossref Full Text | Google Scholar

54. Pillai SK, Abdel-Mohsen M, Guatelli J, Skasko M, Monto A, Fujimoto K, et al. Role of retroviral restriction factors in the interferon-alpha-mediated suppression of HIV-1 in vivo. Proc Natl Acad Sci U.S.A. (2012) 109:3035–40.

PubMed Abstract | Google Scholar

55. Manion M, Rodriguez B, Medvik K, Hardy G, Harding CV, Schooley RT, et al. Interferon-alpha administration enhances CD8+ T cell activation in HIV infection. PloS One. (2012) 7:e30306. doi: 10.1371/journal.pone.0030306

PubMed Abstract | Crossref Full Text | Google Scholar

56. Kwaa AKR, Talana CAG, and Blankson JN. Interferon alpha enhances NK cell function and the suppressive capacity of HIV-specific CD8(+) T cells. J Virol. (2019) 93. doi: 10.1128/JVI.01541-18

PubMed Abstract | Crossref Full Text | Google Scholar

57. Ngo C, Garrec C, Tomasello E, and Dalod M. The role of plasmacytoid dendritic cells (pDCs) in immunity during viral infections and beyond. Cell Mol Immunol. (2024) 21:1008–35. doi: 10.1038/s41423-024-01167-5

PubMed Abstract | Crossref Full Text | Google Scholar

58. Soper A, Kimura I, Nagaoka S, Konno Y, Yamamoto K, Koyanagi Y, et al. Type I interferon responses by HIV-1 infection: association with disease progression and control. Front Immunol. (2017) 8:1823. doi: 10.3389/fimmu.2017.01823

PubMed Abstract | Crossref Full Text | Google Scholar

59. Chen K, Huang J, Zhang C, Huang S, Nunnari G, Wang FX, et al. Alpha interferon potently enhances the anti-human immunodeficiency virus type 1 activity of APOBEC3G in resting primary CD4 T cells. J Virol. (2006) 80:7645–57. doi: 10.1128/JVI.00206-06

PubMed Abstract | Crossref Full Text | Google Scholar

60. Fleith RC, Mears HV, Leong XY, Sanford TJ, Emmott E, Graham SC, et al. IFIT3 and IFIT2/3 promote IFIT1-mediated translation inhibition by enhancing binding to non-self RNA. Nucleic Acids Res. (2018) 46:5269–85. doi: 10.1093/nar/gky191

PubMed Abstract | Crossref Full Text | Google Scholar

61. Goldstone DC, Ennis-Adeniran V, Hedden JJ, Groom HC, Rice GI, Christodoulou E, et al. HIV-1 restriction factor SAMHD1 is a deoxynucleoside triphosphate triphosphohydrolase. Nature. (2011) 480:379–82. doi: 10.1038/nature10623

PubMed Abstract | Crossref Full Text | Google Scholar

62. El-Diwany R, Soliman M, Sugawara S, Breitwieser F, Skaist A, Coggiano C, et al. CMPK2 and BCL-G are associated with type 1 interferon-induced HIV restriction in humans. Sci Adv. (2018) 4:eaat0843. doi: 10.1126/sciadv.aat0843

PubMed Abstract | Crossref Full Text | Google Scholar

63. Dicks MDJ, Betancor G, Jimenez-Guardeno JM, Pessel-Vivares L, Apolonia L, Goujon C, et al. Multiple components of the nuclear pore complex interact with the amino-terminus of MX2 to facilitate HIV-1 restriction. PloS Pathog. (2018) 14:e1007408. doi: 10.1371/journal.ppat.1007408

PubMed Abstract | Crossref Full Text | Google Scholar

64. Jimenez-Guardeno JM, Apolonia L, Betancor G, and Malim MH. Immunoproteasome activation enables human TRIM5alpha restriction of HIV-1. Nat Microbiol. (2019) 4:933–40.

PubMed Abstract | Google Scholar

65. Pincetic A, Kuang Z, Seo EJ, and Leis J. The interferon-induced gene ISG15 blocks retrovirus release from cells late in the budding process. J Virol. (2010) 84:4725–36. doi: 10.1128/JVI.02478-09

PubMed Abstract | Crossref Full Text | Google Scholar

66. Neil SJ, Zang T, and Bieniasz PD. Tetherin inhibits retrovirus release and is antagonized by HIV-1 Vpu. Nature. (2008) 451:425–30. doi: 10.1038/nature06553

PubMed Abstract | Crossref Full Text | Google Scholar

67. Itell HL, Humes D, and Overbaugh J. Several cell-intrinsic effectors drive type I interferon-mediated restriction of HIV-1 in primary CD4(+) T cells. Cell Rep. (2023) 42:112556. doi: 10.1016/j.celrep.2023.112556

PubMed Abstract | Crossref Full Text | Google Scholar

68. Soliman M, El-Diwany R, Wheelan S, Thomas DL, and Balagopal A. Identification of CMPK2 as an interferon stimulated gene that restricts HIV infection. J Immunol. (2017) 198:158.12–.12. doi: 10.4049/jimmunol.198.Supp.158.12

Crossref Full Text | Google Scholar

69. Rasaiyaah J, Tan CP, Fletcher AJ, Price AJ, Blondeau C, Hilditch L, et al. HIV-1 evades innate immune recognition through specific cofactor recruitment. Nature. (2013) 503:402–5. doi: 10.1038/nature12769

PubMed Abstract | Crossref Full Text | Google Scholar

70. Andresini O, Rossi MN, Matteini F, Petrai S, Santini T, and Maione R. The long non-coding RNA Kcnq1ot1 controls maternal p57 expression in muscle cells by promoting H3K27me3 accumulation to an intragenic MyoD-binding region. Epigenet Chromatin. (2019) 12:8. doi: 10.1186/s13072-019-0253-1

PubMed Abstract | Crossref Full Text | Google Scholar

71. Mori H, Masahata K, Umeda S, Morine Y, Ishibashi H, Usui N, et al. Risk of carcinogenesis in the biliary epithelium of children with congenital biliary dilatation through epigenetic and genetic regulation. Surg Today. (2022) 52:215–23. doi: 10.1007/s00595-021-02325-2

PubMed Abstract | Crossref Full Text | Google Scholar

72. Mohammad F, Mondal T, and Kanduri C. Epigenetics of imprinted long non-coding RNAs. Epigenetics. (2009) 4:277–86. doi: 10.4161/epi.4.5.9242

PubMed Abstract | Crossref Full Text | Google Scholar

73. Sun W, Yang Y, Xu C, and Guo J. Regulatory mechanisms of long noncoding RNAs on gene expression in cancers. Cancer Genet. (2017) 216-217:105–10. doi: 10.1016/j.cancergen.2017.06.003

PubMed Abstract | Crossref Full Text | Google Scholar

74. Dave VP, Hajjar F, Dieng MM, Haddad É, and Cohen ÉA. Efficient BST2 antagonism by Vpu is critical for early HIV-1 dissemination in humanized mice. Retrovirology. (2013) 10:128. doi: 10.1186/1742-4690-10-128

PubMed Abstract | Crossref Full Text | Google Scholar

75. Pierini V, Gallucci L, Stürzel CM, Kirchhoff F, and Fackler OT. SERINC5 can enhance proinflammatory cytokine production by primary human myeloid cells in response to challenge with HIV-1 particles. J Virol. (2021) 95. doi: 10.1128/JVI.02372-20

PubMed Abstract | Crossref Full Text | Google Scholar

76. Friedman J, Cho WK, Chu CK, Keedy KS, Archin NM, Margolis DM, et al. Epigenetic silencing of HIV-1 by the histone H3 lysine 27 methyltransferase enhancer of Zeste 2. J Virol. (2011) 85:9078–89. doi: 10.1128/JVI.00836-11

PubMed Abstract | Crossref Full Text | Google Scholar

77. Khan S, Iqbal M, Tariq M, Baig SM, and Abbas W. Epigenetic regulation of HIV-1 latency: focus on polycomb group (PcG) proteins. Clin Epigenetics. (2018) 10:14. doi: 10.1186/s13148-018-0441-z

PubMed Abstract | Crossref Full Text | Google Scholar

78. Kauder SE, Bosque A, Lindqvist A, Planelles V, and Verdin E. Epigenetic regulation of HIV-1 latency by cytosine methylation. PloS Pathog. (2009) 5:e1000495. doi: 10.1371/journal.ppat.1000495

PubMed Abstract | Crossref Full Text | Google Scholar

79. Han P and Chang CP. Long non-coding RNA and chromatin remodeling. RNA Biol. (2015) 12:1094–8. doi: 10.1080/15476286.2015.1063770

PubMed Abstract | Crossref Full Text | Google Scholar

80. Taganov KD, Boldin MP, Chang KJ, and Baltimore D. NF-kappaB-dependent induction of microRNA miR-146, an inhibitor targeted to signaling proteins of innate immune responses. Proc Natl Acad Sci U S A. (2006) 103:12481–6. doi: 10.1073/pnas.0605298103

PubMed Abstract | Crossref Full Text | Google Scholar

81. Yu T, Ju Z, Luo M, Hu R, Teng Y, Xie L, et al. Elevated expression of miR-146a correlates with high levels of immune cell exhaustion markers and suppresses cellular immune function in chronic HIV-1-infected patients. Sci Rep. (2019) 9:18829. doi: 10.1038/s41598-019-55100-2

PubMed Abstract | Crossref Full Text | Google Scholar

82. Harper MS, Guo K, Gibbert K, Lee EJ, Dillon SM, Barrett BS, et al. Interferon-alpha subtypes in an ex vivo model of acute HIV-1 infection: expression, potency and effector mechanisms. PloS Pathog. (2015) 11:e1005254.

PubMed Abstract | Google Scholar

83. Tauzin A, Espinosa Ortiz A, Blake O, Soundaramourty C, Joly-Beauparlant C, Nicolas A, et al. Differential inhibition of HIV replication by the 12 interferon alpha subtypes. J Virol. (2021) 95:e0231120. doi: 10.1128/JVI.02311-20

PubMed Abstract | Crossref Full Text | Google Scholar

84. Karakoese Z, Schwerdtfeger M, Karsten CB, Esser S, Dittmer U, and Sutter K. Distinct type I interferon subtypes differentially stimulate T cell responses in HIV-1-infected individuals. Front Immunol. (2022) 13:936918. doi: 10.3389/fimmu.2022.936918

PubMed Abstract | Crossref Full Text | Google Scholar

85. Frissen PHJ, van der Ende ME, Ten Napel CHH, Weigel HM, Schreij GS, Kauffmann RH, et al. Zidovudine and Interferon- Combination Therapy versus Zidovudine Mono therapy in Subjects with Symptomatic Human Immunodeficiency Virus Type 1 Infection. J Infect Dis. (1994) 169:1351–5. doi: 10.1093/infdis/169.6.1351

PubMed Abstract | Crossref Full Text | Google Scholar

86. Emilie D, Burgard M, Lascoux-Combe C, Laughlin M, Krzysiek R, Pignon C, et al. Early control of HIV replication in primary HIV-1 infection treated wi th antiretroviral drugs and pegylated IFNα: results from the Primofero n A (ANRS 086) Study. AIDS. (2001) 15:1435–7. doi: 10.1097/00002030-200107270-00014

PubMed Abstract | Crossref Full Text | Google Scholar

87. Adalid-Peralta L, Godot V, Colin C, Krzysiek R, Tran T, Poignard P, et al. Stimulation of the primary anti-HIV antibody response by IFN-alpha in patients with acute HIV-1 infection. J Leukoc Biol. (2008) 83:1060–7. doi: 10.1189/jlb.1007675

PubMed Abstract | Crossref Full Text | Google Scholar

88. Boue F, Reynes J, Rouzioux C, Emilie D, Souala F, Tubiana R, et al. Alpha interferon administration during structured interruptions of combination antiretroviral therapy in patients with chronic HIV-1 infection: INTERVAC ANRS 105 trial. AIDS. (2011) 25:115–8. doi: 10.1097/QAD.0b013e328340a1e7

PubMed Abstract | Crossref Full Text | Google Scholar

89. Azzoni L, Foulkes AS, Papasavvas E, Mexas AM, Lynn KM, Mounzer K, et al. Pegylated Interferon alfa-2a monotherapy results in suppression of HIV type 1 replication and decreased cell-associated HIV DNA integration. J Infect Dis. (2013) 207:213–22. doi: 10.1093/infdis/jis663

PubMed Abstract | Crossref Full Text | Google Scholar

90. Pinkevych M, Cromer D, Tolstrup M, Grimm AJ, Cooper DA, Lewin SR, et al. HIV reactivation from latency after treatment interruption occurs on average every 5–8 days–implications for HIV remission. PloS Pathog. (2015) 11:e1005000. doi: 10.1371/journal.ppat.1005000

PubMed Abstract | Crossref Full Text | Google Scholar

91. Li JZ, Etemad B, Ahmed H, Aga E, Bosch RJ, Mellors JW, et al. The size of the expressed HIV reservoir predicts timing of viral rebound after treatment interruption. AIDS. (2016) 30:343–53.

Google Scholar

92. Cha L, de Jong E, French MA, and Fernandez S. IFN-alpha exerts opposing effects on activation-induced and IL-7-induced proliferation of T cells that may impair homeostatic maintenance of CD4+ T cell numbers in treated HIV infection. J Immunol. (2014) 193:2178–86. doi: 10.4049/jimmunol.1302536

PubMed Abstract | Crossref Full Text | Google Scholar

93. Nguyen TP, Bazdar DA, Mudd JC, Lederman MM, Harding CV, Hardy GA, et al. Interferon-alpha inhibits CD4 T cell responses to interleukin-7 and interleukin-2 and selectively interferes with Akt signaling. J Leukoc Biol. (2015) 97:1139–46. doi: 10.1189/jlb.4A0714-345RR

PubMed Abstract | Crossref Full Text | Google Scholar

94. Di Martino V, Thevenot T, Colin JF, Boyer N, Martinot M, Degos F, et al. Influence of HIV infection on the response to interferon therapy and the long-term outcome of chronic hepatitis B. Gastroenterology. (2002) 123:1812–22. doi: 10.1053/gast.2002.37061

PubMed Abstract | Crossref Full Text | Google Scholar

95. Lane HC, Kovacs JA, Feinberg J, Herpin B, Davey V, Walker R, et al. Anti-retroviral effects of interferon-alpha in AIDS-associated Kaposi’s sarcoma. Lancet. (1988) 2:1218–22.

PubMed Abstract | Google Scholar

96. Prestileo T, Mazzola G, Di Lorenzo F, Colletti P, Vitale F, Ferraro D, et al. Response-adjusted alpha-interferon therapy for chronic hepatitis C in HIV-infected patients. Int J Antimicrob Agents. (2000) 16:373–8. doi: 10.1016/S0924-8579(00)00259-4

PubMed Abstract | Crossref Full Text | Google Scholar

97. Giron LB, Colomb F, Papasavvas E, Azzoni L, Yin X, Fair M, et al. Interferon-alpha alters host glycosylation machinery during treated HIV infection. EBioMedicine. (2020) 59:102945. doi: 10.1016/j.ebiom.2020.102945

PubMed Abstract | Crossref Full Text | Google Scholar

98. Angel JB, Greaves W, Long J, Ward D, Rodriguez AE, Scevola D, et al. Virologic and immunologic activity of PegIntron in HIV disease. AIDS. (2009) 23:2431–8. doi: 10.1097/QAD.0b013e32832f30ca

PubMed Abstract | Crossref Full Text | Google Scholar

99. Skillman DR, Malone JL, Decker CF, Wagner KF, Mapou RL, Liao MJ, et al. Phase I trial of interferon alfa-n3 in early-stage human immunodeficiency virus type 1 disease: evidence for drug safety, tolerance, and antiviral activity. J Infect Dis. (1996) 173:1107–14. doi: 10.1093/infdis/173.5.1107

PubMed Abstract | Crossref Full Text | Google Scholar

100. Lane HC, Davey V, Kovacs JA, Feinberg J, Metcalf JA, Herpin B, et al. Interferon-alpha in patients with asymptomatic human immunodeficiency virus (HIV) infection. A randomized, placebo-controlled trial. Ann Intern Med. (1990) 112:805–11. doi: 10.7326/0003-4819-112-11-805

PubMed Abstract | Crossref Full Text | Google Scholar

101. Wei X, Zhang L, Yang Y, Hou Y, Xu Y, Wang Z, et al. LL-37 transports immunoreactive cGAMP to activate STING signaling and enhance interferon-mediated host antiviral immunity. Cell Rep. (2022) 39:110880. doi: 10.1016/j.celrep.2022.110880

PubMed Abstract | Crossref Full Text | Google Scholar

102. Carnero E, Barriocanal M, Segura V, Guruceaga E, Prior C, Borner K, et al. Type I interferon regulates the expression of long non-coding RNAs. Front Immunol. (2014) 5:548. doi: 10.3389/fimmu.2014.00548

PubMed Abstract | Crossref Full Text | Google Scholar

103. Adams BD, Parsons C, Walker L, Zhang WC, and Slack FJ. Targeting noncoding RNAs in disease. J Clin Invest. (2017) 127:761–71. doi: 10.1172/JCI84424

PubMed Abstract | Crossref Full Text | Google Scholar

104. Valadkhan S and Fortes P. Regulation of the interferon response by lncRNAs in HCV infection. Front Microbiol. (2018) 9:181. doi: 10.3389/fmicb.2018.00181

PubMed Abstract | Crossref Full Text | Google Scholar

105. Fu D, Shi Y, Liu JB, Wu TM, Jia CY, Yang HQ, et al. Targeting long non-coding RNA to therapeutically regulate gene expression in cancer. Mol Ther Nucleic Acids. (2020) 21:712–24. doi: 10.1016/j.omtn.2020.07.005

PubMed Abstract | Crossref Full Text | Google Scholar

106. Riddler SA, Para M, Benson CA, Mills A, Ramgopal M, DeJesus E, et al. Vesatolimod, a toll-like receptor 7 agonist, induces immune activation in virally suppressed adults living with human immunodeficiency virus-1. Clin Infect Dis. (2021) 72:e815–e24. doi: 10.1093/cid/ciaa1534

PubMed Abstract | Crossref Full Text | Google Scholar

107. Borducchi EN, Liu J, Nkolola JP, Cadena AM, Yu WH, Fischinger S, et al. Publisher Correction: Antibody and TLR7 agonist delay viral rebound in SHIV-infected monkeys. Nature. (2018) 564:E8. doi: 10.1038/s41586-018-0721-y

PubMed Abstract | Crossref Full Text | Google Scholar

108. Borducchi EN, Cabral C, Stephenson KE, Liu J, Abbink P, Ng’ang’a D, et al. Ad26/MVA therapeutic vaccination with TLR7 stimulation in SIV-infected rhesus monkeys. Nature. (2016) 540:284–7. doi: 10.1038/nature20583

PubMed Abstract | Crossref Full Text | Google Scholar

Keywords: antiviral mechanisms, HIV-1 infection, IFN-α therapy, immunomodulation, interferons

Citation: Zhu L, Ji J, Xiao J, Wang F, Yu J, Liu Y, Zhang Y, Wu H, Su B, Lu X and Zhang T (2025) Interferons in HIV-1 infection: mechanisms, antiviral potentials, and therapeutic challenges. Front. Immunol. 16:1736658. doi: 10.3389/fimmu.2025.1736658

Received: 31 October 2025; Accepted: 05 December 2025; Revised: 02 December 2025;
Published: 18 December 2025.

Edited by:

Laura Fantuzzi, National Institute of Health (ISS), Italy

Reviewed by:

Elena Martinelli, Northwestern University, United States
Daniel Sepúlveda-Crespo, Carlos III Health Institute (ISCIII), Spain

Copyright © 2025 Zhu, Ji, Xiao, Wang, Yu, Liu, Zhang, Wu, Su, Lu and Zhang. 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: Bin Su, Ymluc3VAY2NtdS5lZHUuY24=; Xiaofan Lu, bHV4aWFvZmFuMjAwOGhrQGNjbXUuZWR1LmNu; Tong Zhang, enRfZG9jQGNjbXUuZWR1LmNu

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