Therapeutic Potential of Anti-Interferon α Vaccination on SjS-Related Features in the MRL/lpr Autoimmune Mouse Model.

Sjögren's syndrome (SjS) is a frequent systemic autoimmune disease responsible for a major decrease in patients' quality of life, potentially leading to life-threatening conditions while facing an unmet therapeutic need. Hence, we assessed the immunogenicity, efficacy, and tolerance of IFN-Kinoid (IFN-K), an anti-IFNα vaccination strategy, in a well-known mouse model of systemic autoimmunity with SjS-like features: MRL/MpJ-Faslpr/lpr (MRL/lpr) mice. Two cohorts (with ISA51 or SWE01 as adjuvants) of 26 female MRL/lpr were divided in parallel groups, "controls" (not treated, PBS and Keyhole Limpet Hemocyanin [KLH] groups) or "IFN-K" and followed up for 122 days. Eight-week-old mice received intra-muscular injections (days 0, 7, 28, 56 and 84) of PBS, KLH or IFN-K, emulsified in the appropriate adjuvant, and blood samples were serially collected. At sacrifice, surviving mice were euthanized and their organs were harvested for histopathological analysis (focus score in salivary/lacrimal glands) and IFN signature evaluation. SjS-like features were monitored. IFN-K induced a disease-modifying polyclonal anti-IFNα antibody response in all treated mice with high IFNα neutralization capacities, type 1 IFN signature's reduction and disease features' (ocular and oral sicca syndrome, neuropathy, focus score, glandular production of BAFF) improvement, as reflected by the decrease in Murine Sjögren's Syndrome Disease Activity Index (MuSSDAI) modelled on EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI). No adverse effects were observed. We herein report on the strong efficacy of an innovative anti-IFNα vaccination strategy in a mouse model of SjS, paving the way for further clinical development (a phase IIb trial has just been completed in systemic lupus erythematosus with promising results).

Vitamin C Enhances Antiviral Functions of Lung Epithelial Cells.

Vitamin C is well documented to have antiviral functions; however, there is limited information about its effect on airway epithelial cells-the first cells to encounter infections. Here, we examined the effect of vitamin C on human bronchial epithelium transformed with Ad12-SV40 2B (BEAS-2B) cells, and observed that sodium-dependent vitamin C transporter 2 (SVCT2) was the primary vitamin C transporter. Transcriptomic analysis revealed that treating BEAS-2B cells with vitamin C led to a significant upregulation of several metabolic pathways and interferon-stimulated genes (ISGs) along with a downregulation of pathways involved in lung injury and inflammation. Remarkably, vitamin C also enhanced the expression of the viral-sensing receptors retinoic acid-inducible gene 1 (RIG-1) and melanoma differentiation-associated protein 5 (MDA-5), which was confirmed at the protein and functional levels. In addition, the lungs of l-gulono-γ-lactone oxidase knockout (GULO-KO) mice also displayed a marked decrease in these genes compared to wild-type controls. Collectively, our findings indicate that vitamin C acts at multiple levels to exert its antiviral and protective functions in the lungs.

IFN-α: A key therapeutic target for multiple autoimmune rheumatic diseases.

Interferon (IFN)-α has emerged as a major therapeutic target for several autoimmune rheumatic diseases. In this review, we focus on clinical and preclinical advances in anti-IFN-α treatments in systemic lupus erythematosus (SLE), primary Sjögren syndrome (pSS), systemic sclerosis (SSc), and dermatomyositis (DM), for which a high medical need persists. Promising achievements were obtained following direct IFN-α neutralization, targeting its production through the cytosolic nucleic acid sensor pathways or by blocking its downstream effects through the type I IFN receptor. We further focus on molecular profiling and data integration approaches as crucial steps to select patients most likely to benefit from anti-IFN-α therapies within a precision medicine approach.

Mild COVID-19 despite autoantibodies against type I IFNs in autoimmune polyendocrine syndrome type 1.

Autoantibodies against IFN-α and IFN-ω (type I IFNs) were recently reported as causative for severe COVID-19 in the general population. Autoantibodies against IFN-α and IFN-ω are present in almost all patients with autoimmune polyendocrine syndrome type 1 (APS-1) caused by biallelic deleterious or heterozygous dominant mutations in AIRE. We therefore hypothesized that autoantibodies against type I IFNs also predispose patients with APS-1 to severe COVID-19. We prospectively studied 6 patients with APS-1 between April 1, 2020 and April 1, 2021. Biobanked pre-COVID-19 sera of APS-1 subjects were tested for neutralizing autoantibodies against IFN-α and IFN-ω. The ability of the patients' sera to block recombinant human IFN-α and IFN-ω was assessed by assays quantifying phosphorylation of signal transducer and activator of transcription 1 (STAT1) as well as infection-based IFN-neutralization assays. We describe 4 patients with APS-1 and preexisting high titers of neutralizing autoantibodies against IFN-α and IFN-ω who contracted SARS-CoV-2, yet developed only mild symptoms of COVID-19. None of the patients developed dyspnea, oxygen requirement, or high temperature. All infected patients with APS-1 were females and younger than 26 years of age. Clinical penetrance of neutralizing autoantibodies against type I IFNs for severe COVID-19 is not complete.

Eltrombopag inhibits Type I interferon-mediated antiviral signaling by decreasing cellular iron.

Thrombocytopenia is common among patients with viral hepatitis, limiting the use of antiviral therapy. Eltrombopag (EP) is a thrombopoietin receptor (TPO-R) agonist that has been approved for treatment of immune thrombocytopenia patients with hepatitis virus infection. Interferon-α (IFN-α) plays a crucial role in the antiviral response, and is recommended as the first-line agent for chronic hepatitis B patients. Here, we investigated whether EP inhibits the production of IFN-stimulated genes (ISGs) induced by IFN-α through the TPO-R-independent pathway by mediating reactive oxygen species production by iron chelation. Our results assessed the inhibitory effect of EP on IFN-α signaling, which contributes to the downregulation of ISGs produced by monocytes and sheds light on the underlying mechanisms using iron chelation to treat patients with hepatitis-related immunological thrombocytopenia.

Novel signatures associated with systemic lupus erythematosus clinical response to IFN-α/-ω inhibition.

OBJECTIVES: We aimed to identify transcriptional gene signatures predictive of clinical response, for pharmacodynamic evaluation, and to provide mechanistic insight into JNJ-55920839, a human IgG1κ neutralizing mAb targeting IFN-α/IFN-ω, in participants with systemic lupus erythematosus (SLE). METHODS: Blood samples were obtained from SLE participants at baseline and up to Day 130, who received six 10 mg/kg IV doses of JNJ-55920839/placebo every 2 weeks. Participants with mild-to-moderate SLE who achieved clinical responses using SLE Disease Activity Index 2000 Responder Index 4-point change were considered responders. Transcriptional signatures from longitudinally collected blood were generated by RNA-Seq; signatures were generated by microarray from baseline blood samples exposed in vitro to JNJ-55920839 versus untreated. RESULTS: Two gene signatures (IFN-I Signaling and Immunoglobulin Immune Response) exhibited pharmacodynamic changes among JNJ-55920839 responders. The Immunoglobulin signature, but not the IFN-I signature, was elevated at baseline in JNJ-55920839 responders. A gene cluster associated with neutrophil-mediated immunity was reduced at baseline in JNJ-55920839 responders, substantiated by lower neutrophil counts in responders. An IFN-I signature was suppressed by JNJ-55920839 in vitro treatment versus untreated blood to a greater extent in responders before in vivo dosing. CONCLUSIONS: These signatures may enable enrichment for treatment responders when using IFN-I-suppressing treatments in SLE.

Pharmacokinetics and Pharmacodynamics of JNJ-55920839, an Antibody Targeting Interferon α/ω, in Healthy Subjects and Subjects with Mild-to-Moderate Systemic Lupus Erythematosus.

BACKGROUND: The interferon (IFN) pathway has been correlated with clinical and serological markers of disease activity in patients with systemic lupus erythematosus (SLE). OBJECTIVE: The pharmacokinetics and pharmacodynamics of JNJ-55920839, a fully human immunoglobulin G1κ antibody targeting IFNα/ω, were investigated. METHODS: In a double-blind, first-in-human study, Part A enrolled 48 healthy adults who received a single dose of placebo/JNJ-55920839 between 0.3 and 15 mg/kg intravenous (IV) or at 1 mg/kg subcutaneous (SC). Part B enrolled 26 adults with SLE who received placebo or JNJ-55920839 10 mg/kg IV 6 times biweekly. Pharmacokinetic parameters were calculated by noncompartmental analysis (NCA) and estimated by nonlinear mixed-effects modeling. RESULTS: JNJ-55920839 pharmacokinetics following a single IV infusion exhibited a biphasic disposition in healthy subjects. Maximum plasma concentration (Cmax) and area under the concentration-time curve values increased dose-proportionally. Mean clearance (CL) after a single IV infusion ranged between 2.28 and 3.09 mL/kg/day. Absolute bioavailability after a single SC injection was ≥ 80.0%. Mean terminal elimination half-life (t1/2) was similar after IV (20.7 to 24.6 days) and SC administration (22.6 days). Steady state of JNJ-55920839 was achieved 6 weeks after multiple 10 mg/kg IV doses in subjects with SLE. Mean steady-state CL and t1/2 were 4.73 mL/kg/day and 14.8 days, respectively. A linear 2-compartment population pharmacokinetic model with 1st-order absorption and elimination adequately characterized the pharmacokinetics; parameters were consistent with NCA estimates. Higher CL was estimated in subjects with SLE compared with healthy subjects, after correcting for body weight. A trend of increased total IFNα/ω levels was observed after treatment with JNJ-55920839. CONCLUSION: Pharmacokinetic and pharmacodynamic analyses of the data from this study demonstrated that there was biphasic disposition in both healthy subjects and subjects with SLE, CL was faster in subjects with SLE, and increases in total IFNα/ω levels were observed in both healthy subjects and subjects with SLE after treatment with JNJ-55920839, thus further development is supported. The study is registered at ClinicalTrials.gov NCT02609789.

Type I Interferon Susceptibility Distinguishes SARS-CoV-2 from SARS-CoV.

SARS-CoV-2, a novel coronavirus (CoV) that causes COVID-19, has recently emerged causing an ongoing outbreak of viral pneumonia around the world. While distinct from SARS-CoV, both group 2B CoVs share similar genome organization, origins to bat CoVs, and an arsenal of immune antagonists. In this report, we evaluate type I interferon (IFN-I) sensitivity of SARS-CoV-2 relative to the original SARS-CoV. Our results indicate that while SARS-CoV-2 maintains similar viral replication to SARS-CoV, the novel CoV is much more sensitive to IFN-I. In Vero E6 and in Calu3 cells, SARS-CoV-2 is substantially attenuated in the context of IFN-I pretreatment, whereas SARS-CoV is not. In line with these findings, SARS-CoV-2 fails to counteract phosphorylation of STAT1 and expression of ISG proteins, while SARS-CoV is able to suppress both. Comparing SARS-CoV-2 and influenza A virus in human airway epithelial cultures, we observe the absence of IFN-I stimulation by SARS-CoV-2 alone but detect the failure to counteract STAT1 phosphorylation upon IFN-I pretreatment, resulting in near ablation of SARS-CoV-2 infection. Next, we evaluated IFN-I treatment postinfection and found that SARS-CoV-2 was sensitive even after establishing infection. Finally, we examined homology between SARS-CoV and SARS-CoV-2 in viral proteins shown to be interferon antagonists. The absence of an equivalent open reading frame 3b (ORF3b) and genetic differences versus ORF6 suggest that the two key IFN-I antagonists may not maintain equivalent function in SARS-CoV-2. Together, the results identify key differences in susceptibility to IFN-I responses between SARS-CoV and SARS-CoV-2 that may help inform disease progression, treatment options, and animal model development.IMPORTANCE With the ongoing outbreak of COVID-19, differences between SARS-CoV-2 and the original SARS-CoV could be leveraged to inform disease progression and eventual treatment options. In addition, these findings could have key implications for animal model development as well as further research into how SARS-CoV-2 modulates the type I IFN response early during infection.

Identification and characterization of human interferon alpha inhibitors through a WISH cell line-based reporter gene assay.

Interferons (IFNs) are important glycoproteins which can stimulate or inhibit up to three hundred different genes encoding proteins involved in antiviral defense mechanisms, inflammation, adaptive immunity, angiogenesis and among other processes. Nevertheless, different genetic alterations may lead to interferon alpha (IFN-α) overproduction in human autoimmune diseases like systemic lupus erythematosus. As a consequence, IFN-α is a central molecule whose activity must be regulated to block their harmful effect on those disorders where the endogenous cytokine production constitutes the etiology of the illnesses. In this work, we evaluate the biological activity of eighty-eight compounds, from our own chemo-library, to find potential IFN-α inhibitors by using a reporter gene assay (RGA) WISH-Mx2/EGFP. We identified some compounds able to modulate negatively the IFN-α activity. The most active IFN-α inhibitors were further studied achieving promising results. In addition, some combinations of the most active compounds were analyzed accomplishing a stronger effect to decrease the IFN-α activity than each compound alone. Furthermore, the complete inhibition of the cytokine activity was reached with some combinations of compounds.

NOS1 inhibits the interferon response of cancer cells by S-nitrosylation of HDAC2.

BACKGROUND: The dysfunction of type I interferon (IFN) signaling is an important mechanism of immune escape and metastasis in tumors. Increased NOS1 expression has been detected in melanoma, which correlated with dysfunctional IFN signaling and poor response to immunotherapy, but the specific mechanism has not been determined. In this study, we investigated the regulation of NOS1 on the interferon response and clarified the relevant molecular mechanisms. METHODS: After stable transfection of A375 cells with NOS1 expression plasmids, the transcription and expression of IFNα-stimulated genes (ISGs) were assessed using pISRE luciferase reporter gene analysis, RT-PCR, and western blotting, respectively. The effect of NOS1 on lung metastasis was assessed in melanoma mouse models. A biotin-switch assay was performed to detect the S-nitrosylation of HDAC2 by NOS1. ChIP-qPCR was conducted to measure the binding of HDAC2, H4K16ac, H4K5ac, H3ac, and RNA polymerase II in the promoters of ISGs after IFNα stimulation. This effect was further evaluated by altering the expression level of HDAC2 or by transfecting the HDAC2-C262A/C274A site mutant plasmids into cells. The coimmunoprecipitation assay was performed to detect the interaction of HDAC2 with STAT1 and STAT2. Loss-of-function and gain-of-function approaches were used to examine the effect of HDAC2-C262A/C274A on lung metastasis. Tumor infiltrating lymphocytes were analyzed by flow cytometry. RESULTS: HDAC2 is recruited to the promoter of ISGs and deacetylates H4K16 for the optimal expression of ISGs in response to IFNα treatment. Overexpression of NOS1 in melanoma cells decreases IFNα-responsiveness and induces the S-nitrosylation of HDAC2-C262/C274. This modification decreases the binding of HDAC2 with STAT1, thereby reducing the recruitment of HDAC2 to the ISG promoter and the deacetylation of H4K16. Moreover, expression of a mutant form of HDAC2, which cannot be nitrosylated, reverses the inhibition of ISG expression by NOS1 in vitro and decreases NOS1-induced lung metastasis and inhibition of tumor infiltrating lymphocytes in a melanoma mouse model. CONCLUSIONS: This study provides evidence that NOS1 induces dysfunctional IFN signaling to promote lung metastasis in melanoma, highlighting NOS1-induced S-nitrosylation of HDAC2 in the regulation of IFN signaling via histone modification.

Distinct Roles of Interferon Alpha and Beta in Controlling Chikungunya Virus Replication and Modulating Neutrophil-Mediated Inflammation.

Type I interferons (IFNs) are key mediators of the innate immune response. Although members of this family of cytokines signal through a single shared receptor, biochemical and functional variation exists in response to different IFN subtypes. While previous work has demonstrated that type I IFNs are essential to control infection by chikungunya virus (CHIKV), a globally emerging alphavirus, the contributions of individual IFN subtypes remain undefined. To address this question, we evaluated CHIKV pathogenesis in mice lacking IFN-ß (IFN-ß knockout [IFN-ß-KO] mice or mice treated with an IFN-ß-blocking antibody) or IFN-α (IFN regulatory factor 7 knockout [IRF7-KO] mice or mice treated with a pan-IFN-α-blocking antibody). Mice lacking either IFN-α or IFN-ß developed severe clinical disease following infection with CHIKV, with a marked increase in foot swelling compared to wild-type mice. Virological analysis revealed that mice lacking IFN-α sustained elevated infection in the infected ankle and in distant tissues. In contrast, IFN-ß-KO mice displayed minimal differences in viral burdens within the ankle or at distal sites and instead had an altered cellular immune response. Mice lacking IFN-ß had increased neutrophil infiltration into musculoskeletal tissues, and depletion of neutrophils in IFN-ß-KO but not IRF7-KO mice mitigated musculoskeletal disease caused by CHIKV. Our findings suggest disparate roles for the IFN subtypes during CHIKV infection, with IFN-α limiting early viral replication and dissemination and IFN-ß modulating neutrophil-mediated inflammation.IMPORTANCE Type I interferons (IFNs) possess a range of biological activity and protect against a number of viruses, including alphaviruses. Despite signaling through a shared receptor, there are established biochemical and functional differences among the IFN subtypes. The significance of our research is in demonstrating that IFN-α and IFN-ß both have protective roles during acute chikungunya virus (CHIKV) infection but do so by distinct mechanisms. IFN-α limits CHIKV replication and dissemination, whereas IFN-ß protects from CHIKV pathogenesis by limiting inflammation mediated by neutrophils. Our findings support the premise that the IFN subtypes have distinct biological activities in the antiviral response.

ER intrabody-mediated inhibition of interferon α secretion by mouse macrophages and dendritic cells.

Interferon α (IFNα) counteracts viral infections by activating various IFNα-stimulated genes (ISGs). These genes encode proteins that block viral transport into the host cell and inhibit viral replication, gene transcription and translation. Due to the existence of 14 different, highly homologous isoforms of mouse IFNα, an IFNα knockout mouse has not yet been established by genetic knockout strategies. An scFv intrabody for holding back IFNα isoforms in the endoplasmic reticulum (ER) and thus counteracting IFNα secretion is reported. The intrabody was constructed from the variable domains of the anti-mouse IFNα rat monoclonal antibody 4EA1 recognizing the 5 isoforms IFNα1, IFNα2, IFNα4, IFNα5, IFNα6. A soluble form of the intrabody had a KD of 39 nM to IFNα4. It could be demonstrated that the anti-IFNα intrabody inhibits clearly recombinant IFNα4 secretion by HEK293T cells. In addition, the secretion of IFNα4 was effectively inhibited in stably transfected intrabody expressing RAW 264.7 macrophages and dendritic D1 cells. Colocalization of the intrabody with IFNα4 and the ER marker calnexin in HEK293T cells indicated complex formation of intrabody and IFNα4 inside the ER. Intracellular binding of intrabody and antigen was confirmed by co-immunoprecipitation. Complexes of endogenous IFNα and intrabody could be visualized in the ER of Poly (I:C) stimulated RAW 264.7 macrophages and D1 dendritic cells. Infection of macrophages and dendritic cells with the vesicular stomatitis virus VSV-AV2 is attenuated by IFNα and IFNß. The intrabody increased virus proliferation in RAW 264.7 macrophages and D1 dendritic cells under IFNß-neutralizing conditions. To analyze if all IFNα isoforms are recognized by the intrabody was not in the focus of this study. Provided that binding of the intrabody to all isoforms was confirmed, the establishment of transgenic intrabody mice would be promising for studying the function of IFNα during viral infection and autoimmune diseases.

HIV-1-Mediated Suppression of IFN-α Production Is Associated with Inhibition of IRF-7 Translocation and PI3K/akt Pathway in Plasmacytoid Dendritic Cells.

Interferon-α (IFN-α) plays a vital role in combating viral infections especially in the early control after infection. However, the HIV infection has shown substantial level of suppression of IFN-α secretion during initial phase of infection. The reasons behind this impairment are still obscure. As plasmacytoid dendritic cells (pDCs) are the major producers of this cytokine, the mechanisms of HIV-1-mediated suppression of IFN-α production by pDCs using the primary pDCs were explored. The nuclear translocation of the interferon regulatory factor (IRF)-7, a transcription factor for IFN-α genes, is essential for the initiation of IFN-α production in pDCs. The HIV-1-exposed pDCs did not show the translocation of IRF-7 into the nucleus in our experiments. Furthermore, it was also observed that HIV-1 inhibited AKT phosphorylation of PI3K/akt pathway in pDCs, an important step for IRF-7 translocation to nucleus. HIV-1-induced inhibition of AKT phosphorylation and IRF-7 translocation was evident even in the presence of Toll-like receptor-7 agonist stimulation and correlated with IFN-α suppression. The findings suggest that HIV-1 may alter AKT phosphorylation to inhibit the translocation of IRF-7 into pDC nucleus, leading to IFN-α suppression, and this may be the reason for IFN-α abrogation observed in recently infected HIV patients. Understanding of interactions between HIV-1 and signaling pathways leading to IFN-α secretion may provide targets for immune intervention.

Induction of interleukin 6 impairs the anti-HBV efficiency of IFN-α in human hepatocytes through upregulation of SOCS3.

Interleukin 6 (IL-6) is a pleiotropic cytokine with pivotal functions in the regulation of the biological responses of several target cells, including hepatocytes. Previous studies have shown that serum IL-6 levels are increased in hepatitis B patients. However, the role of IL-6 in modulating the anti-hepatitis B virus (HBV) activity of interferon-α (IFN-α) remains unclear. In this study, we found that both HBV and viral proteins could induce the expression of IL-6 in hepatocytes (LO2 and HepG2). Exogenous IL-6 had no effect on HBV replication, whereas knockdown of IL-6 expression by RNAi inhibited that. Interestingly, IFN-α markedly induced IL-6 expression in hepatocytes, especially in HBV replicating hepatocytes. In turn, IL-6 impaired the anti-HBV efficiency of IFN-α by decreases the expression of IFN-α downstream effectors by upregulation of suppressor of cytokine signaling-3 (SOCS3). Furthermore, we demonstrated that downregulation of SOCS3 improved IFN antiviral activity to some extent in HBV replicating hepatocytes. These data provided new insights for a better understanding of the mechanism of IFN-α resistance and may represent a novel therapeutic strategy to efficiently target HBV infection.

The osteopontin-CD44 axis in hepatic cancer stem cells regulates IFN signaling and HCV replication.

Osteopontin (OPN) is involved in cell proliferation, migration, inflammation, and tumor progression in various tissues. OPN induces stemness by interacting with CD44, but the functional relevance of OPN-mediated interferon (IFN) signaling and hepatitis C virus (HCV) replication in stem cell populations remains unclear. In this study, we investigated the effect of OPN on HCV replication and IFN signaling in cancer stem cells (CSCs) positive for epithelial cell adhesion molecule (EpCAM) and CD44. We show that the EpCAM+/CD44+ CSCs show marked HCV replication when compared to EpCAM-/CD44- cells. In addition, OPN significantly enhances this HCV replication in EpCAM+/CD44+ CSCs and markedly suppresses IFN-stimulated gene expression. The GSK-3ß inhibitor BIO increases the EpCAM+/CD44+ CSC population and OPN expression and impairs IFN signaling via STAT1 degradation. Taken together, our data suggest that OPN enhances HCV replication in the EpCAM+/CD44+ CSCs, while it also negatively regulates the IFN signaling pathway via inhibition of STAT1 phosphorylation and degradation. Therefore, OPN may represent a novel therapeutic target for treating HCV-related hepatocellular carcinoma.

Interferon alpha: The key trigger of type 1 diabetes.

IFNα is a cytokine essential to a vast array of immunologic processes. Its induction early in the innate immune response provides a priming mechanism that orchestrates numerous subsequent pathways in innate and adaptive immunity. Despite its beneficial effects in viral infections IFNα has been reported to be associated with several autoimmune diseases including autoimmune thyroid disease, systemic lupus erythematosus, rheumatoid arthritis, primary biliary cholangitis, and recently emerged as a major cytokine that triggers Type 1 Diabetes. In this review, we dissect the role of IFNα in T1D, focusing on the potential pathophysiological mechanisms involved. Evidence from human and mouse studies indicates that IFNα plays a key role in enhancing islet expression of HLA-I in patients with T1D, thereby increasing autoantigen presentation and beta cell activation of autoreactive cytotoxic CD8 T-lymphocytes. The binding of IFNα to its receptor induces the secretion of chemokines, attracting monocytes, T lymphocytes, and NK cells to the infected tissue triggering autoimmunity in susceptible individuals. Furthermore, IFNα impairs insulin production through the induction of endoplasmic reticulum stress as well as by impairing mitochondrial function. Due to its central role in the early phases of beta cell death, targeting IFNα and its pathways in genetically predisposed individuals may represent a potential novel therapeutic strategy in the very early stages of T1D.

Reversing interferon-alpha neurotoxicity in a HIV-associated neurocognitive disorder mouse model.

OBJECTIVE: Increased brain interferon-alpha (IFNα) is associated with neurodegenerative disorders, including HIV-associated neurocognitive disorders (HAND). HAND occurs in approximately 50% of individuals with HIV despite combined antiretroviral therapy (cART). Therefore, adjunctive therapies must be developed that prevent progression of mild forms of HAND to HIV-associated dementia. Increased IFNα in the CNS has been associated with HAND in patients and in a HAND mouse model. DESIGN AND METHODS: B18R binds IFNα and ameliorates HAND mouse brain histopathology (HIV encephalitis). The HAND model was used to determine if B18R with cART is superior to cART. Behavioral testing [Object recognition Test (ORT)] was used to show that B18R can reverse behavioral deficits. Rat neuronal cultures were used to investigate mechanisms of IFNα neurotoxicity. RESULTS: Mouse brain immunohistochemistry and densitometry suggests that B18R with a common cART regimen improve histopathological markers better than cART alone. B18R reverses ORT behavioral abnormalities in HAND mice. IFNα-treated rat neurons show decreases in PSD-95, suggesting that dendritic spine architecture is disrupted. Decreases in Arf1, a GTP-binding protein, and AMPA receptors on the surface of rat neurons exposed to IFNα suggest the mechanism of IFNα neurotoxicity may relate to decreased Arf1 resulting in destabilization of dendritic spines, decreased PSD-95 expression, and internalization of AMPA receptors. CONCLUSION: B18R reversal of HAND in the mouse model is further evidence that the treatment of IFNα in individuals with HAND could be a viable adjunctive treatment. Investigating pathways of IFNα neurotoxicity may lead to more specific treatments.

Interferon-α Silencing by Small Interference RNA Increases Adenovirus Transduction and Transgene Expression in Huh7 Cells.

Adenoviruses are the most common vectors used in clinical trials of gene therapy. In 2017, 21.2% of clinical trials used rAds as vectors. Systemic administration of rAds results in high tropism in the liver. Interferon types α and ß are the major antiviral cytokines which orchestrate the host's immune response against rAd, limiting therapeutic gene expression and preventing subsequent vector administration. siRNA is small double-strand RNAs that temporally inhibit the expression of a specific gene. The aim is to evaluate the effect of IFN-α blocking by a specific siRNA on Ad-GFP transduction and on transgene expression in Huh7 cells in culture. Huh7 cells were cultured in DMEM and transfected with 70 nM of siRNA-IFN-α. Six hours later, the cells were exposed to 1 × 109 vp/ml of rAd-GFP for 24 h. Expression of IFN-α, TNF-α and the PKR gene was determined by RT-qPCR. Percentage of transduction was analyzed by flow cytometry and by qPCR. GFP expression was determined by western blot. 70 nM of siRNA-IFN-α inhibited 96% of IFN-α and 65% of TNF-α gene expression compared to an irrelevant siRNA. Percentage of transduction and transgene expression increased in these cells compared to an irrelevant siRNA. Inhibition of IFN-α expression by siRNA-IFN-α enabled a higher level of transduction and transgene expression GFP, highlighting the role of IFN-α in the elimination of adenovirus in transduced cells and thus suggesting that its inhibition could be an important strategy for gene therapy in clinical trials using adenovirus as a vector directed to liver diseases.

Reduced Chronic Lymphocyte Activation following Interferon Alpha Blockade during the Acute Phase of Simian Immunodeficiency Virus Infection in Rhesus Macaques.

Pathogenic human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection of humans and rhesus macaques (RMs) induces persistently high production of type I interferon (IFN-I), which is thought to contribute to disease progression. To elucidate the specific role of interferon alpha (IFN-α) in SIV pathogenesis, 12 RMs were treated prior to intravenous (i.v.) SIVmac239 infection with a high or a low dose of an antibody (AGS-009) that neutralizes most IFN-α subtypes and were compared with six mock-infused, SIV-infected controls. Plasma viremia was measured postinfection to assess the effect of IFN-α blockade on virus replication, and peripheral blood and lymphoid tissue samples were analyzed by immunophenotypic staining. Consistent with the known antiviral effect of IFN-I, high-dose AGS-009 treatment induced a modest increase in acute-phase viral loads versus controls. Four out of 6 RMs receiving a high dose of AGS-009 also experienced an early decline in CD4+ T cell counts that was associated with progression to AIDS. Interestingly, 50% of the animals treated with AGS-009 (6/12) developed AIDS within 1 year of infection compared with 17% (1/6) of untreated controls. Finally, blockade of IFN-α decreased the levels of activated CD4+ and CD8+ T cells, as well as B cells, as measured by PD-1 and/or Ki67 expression. The lower levels of activated lymphocytes in IFN-α-blockaded animals supports the hypothesis that IFN-α signaling contributes to lymphocyte activation during SIV infection and suggests that this signaling pathway is involved in controlling virus replication during acute infection. The potential anti-inflammatory effect of IFN-α blockade should be explored as a strategy to reduce immune activation in HIV-infected individuals.IMPORTANCE Interferon alpha (IFN-α) is a member of a family of molecules (type I interferons) that prevent or limit virus infections in mammals. However, IFN-α production may contribute to the chronic immune activation that is thought to be the primary cause of immune decline and AIDS in HIV-infected patients. The study presented here attempts to understand the contribution of IFN-α to the natural history and progression of SIV infection of rhesus macaques, the primary nonhuman primate model system for testing hypotheses about HIV infection in humans. Here, we show that blockade of IFN-α action promotes lower chronic immune activation but higher early viral loads, with a trend toward faster disease progression. This study has significant implications for new treatments designed to impact the type I interferon system.

Immunogenicity of branched polyethylene glycol modified interferon alpha.

AIM: To assess the immunogenicity of Peginterferon alpha-2 b(Pegberon) and its effect on the efficacy and safety in phase III clinical trial, by comparing it with the control drug Pegasys. METHODS: 770 patients were recruited in total. 509 were treated with Pegberon plus ribavirin and 261 were treated with Pegasys plus ribavirin. After treatment of 12 and 24 weeks, plasma samples were collected from individual patients for detecting the anti-therapeutic antibodies (ATA) and hepatitis C RNA(HCV RNA), to evaluate the production of antibodies and their adverse effect on the efficacy and safety of the treatments. With data obtained from the treatments with Pegberon or Pegasys, gross comparison analysis was performed. RESULTS: The incidence of treatment-induced neutralizing antibodies (NAb) of Pegberon group (0.7%, 3/454) was significantly lower than Pegasys group (5.0%,12/238)(p < .001). Among all patients, the rates of sustained virological response 24 (SVR24) were significantly different between baseline ATA positive (60.7%,34/56) and baseline ATA negative patients (76.2%,544/714)(p = .010), between baseline NAb positive (36.0%,9/25) and baseline NAb negative patients (76.4%,569/745)(p < .001) and between induced ATA positive (72.7%,40/55) and sustained ATA negative patients(84.0%,492/586)(p = .034). The incidence of potential immunogenicity-related adverse reactions (AR) showed no significant difference between Pegberon (55.6%,283/509) and Pegasys groups (53.6%,140/261)(p = .605) and the profiles of these AR were also similar between the two groups. CONCLUSION: The incidence of treatment-induced Nab in Pegasys group was significantly higher than the Pegberon group. Baseline ATA, induced ATA and baseline NAb all affected the efficacy. The profiles of potential immunogenicity-related AR were similar between two drug groups, indicating the immunogenicity had no significant adverse effect on safety.