Impaired Viral Clearance Research Articles

Peritubular and Tubulointerstitial Inflammation as Predictors of Impaired Viral Clearance in Polyomavirus Nephropathy.

Introduction: Polyomavirus-associated nephropathy (BKPyVAN) is a common complication in kidney transplant recipients. The histological changes in the context of BKPyVAN and their association with the viral load and outcomes are still being investigated. Methods: This retrospective study involved 100 adult patients transplanted between 2000 and 2021, with available archived biopsy slides, aiming to analyze associations between viral load clearance in the blood (reduction in BKPyVAN-DNAemia below detection level) and histological features in biopsy-proven BKPyVAN. A kidney pathologist blinded to the clinical data reassessed the BANFF 2019 lesion scores in the BKPyVAN index biopsy. The primary endpoint was viral clearance three months after the diagnosis. Results: The presence of tubulointerstitial inflammation, peritubular capillaritis, and higher PVN Class at the diagnosis was linked to a reduced likelihood of viral clearance three months later (interstitial inflammation OR = 0.2, 95% CI [0.07-0.55], tubulitis OR = 0.39, 95% CI [0.21-0.73], peritubular capillaritis OR = 0.25, 95% CI [0.08-0.82], PVN Score OR = 0.1, 95% CI [0.03-0.4]), independently of other covariates. Combining the four lesions using the ROC analysis enhanced their capability to predict persistent BK viremia after 3 months with an AUC of 0.94. Conclusions: The presence of interstitial inflammation, tubulitis, and peritubular capillaritis, as well as the higher PVN Score, was associated with an up to 90% lower likelihood of viral load clearance three months post-diagnosis. These findings underscore the importance of histological evaluation as a surrogate of subsequent viral clearance and offer valuable insights for the management of BKPyVAN.

Immune dysregulation as a leading principle for lymphoma development in diverse immunological backgrounds

Lymphoma is a heterogeneous group of malignancies arising from lymphocytes, which poses a significant challenge in terms of diagnosis and treatment due to its diverse subtypes and underlying mechanisms. This review aims to explore the shared and distinct features of various forms of lymphoma predisposing conditions, with a focus on genetic, immunological and molecular aspects. While diseases such as autoimmune disorders, inborn errors of immunity and iatrogenic immunodeficiencies are biologically and immunologically distinct, each of these diseases results in profound immune dysregulation and a predisposition to lymphoma development. Interestingly, the increased risk is often skewed towards a particular subtype of lymphoma. Patients with inborn errors of immunity in particular present with extreme forms of lymphoma predisposition, providing a unique opportunity to study the underlying mechanisms. External factors such as chronic infections and environmental exposures further modulate the risk of lymphoma development. Common features of conditions predisposing to lymphoma include: persistent inflammation, recurrent DNA damage or malfunctioning DNA repair, impaired tumor surveillance and viral clearance, and dysregulation of fundamental cellular processes such as activation, proliferation and apoptosis. Our growing understanding of the underlying mechanisms of lymphomagenesis provides opportunities for early detection, prevention and tailored treatment of lymphoma development.

Vitamin A deficient mice exhibit impaired viral clearance, increased inflammation and altered immune response during respiratory viral infection

Abstract Vitamin A deficiency (VAD) is prevalent in developing countries and is associated with increased mortality after respiratory viral infections. Vitamin A can only be acquired through the diet, and millions of pregnant women and young children are deficient; however, the effects of VAD on the immune response are not completely understood. Pregnant C57BL/6 mice were placed on a VAD diet at gestational day five, pups remained on this diet after birth. At 8 weeks of age, control and VAD mice were infected intranasally with a sub-lethal dose of Sendai Virus (SeV), a natural mouse pathogen. Body weight loss in control mice peaked at day 7 post-infection, while VAD mice continued to lose weight until day 11 post-infection. This was associated with delayed clearance of virus, elevated cytokines TNFα, IL-4, and IL-17, and increased numbers of inflammatory cells in the VAD lungs. Flow cytometry showed significantly increased percentages of neutrophils on days 7 and 21, increased NK cells on day 7, increased macrophages on day 7 and increased MHC Class IIhi macrophages on days 7 and 21. In the adaptive response, CD4+ and CD8+ T cells were decreased on day 7 and increased on day 21. CD4+ T cell subsets showed increased CD4+Foxp3+ T cells on day 7 and increased CD4+Tbet+ T cells on day 21. B lymphocytes were lower at all time points. Together, this suggests that VAD affects multiple cell populations in both the innate and adaptive immune responses to viral infection in the lung, Supported by Grants from Sigma Xi Grant in Aid of Research, Saint Louis University College of Arts and Sciences Knoedler Award, and Saint Louis University College of Arts and Sciences Graduate Undergraduate Award.

Valosin-containing protein (VCP/p97) inhibition reduces viral clearance and induces toxicity associated with muscular damage

Valosin-containing protein (VCP)/p97 has emerged as a central regulator of the ubiquitin–proteasome system by connecting ubiquitylation and degradation. The development of CB-5083, an ATPase D2-domain-selective and orally bioavailable inhibitor of VCP/p97, allows targeting of the ubiquitin–proteasome system in human diseases. In this study, we evaluated the effect of CB-5083 on the immune response in mice by using the lymphocytic choriomeningitis virus (LCMV) as an infection model. We demonstrate that LCMV infection increased the susceptibility to CB-5083 treatment in a CD8-independent manner. Administration of CB-5083 to mice reduced the cytotoxic T cell response and impaired viral clearance. Compared to uninfected cells, CB-5083 treatment enhanced the unfolded protein response in LCMV-infected cells. Administration of CB-5083 during the expansion of CD8+ T cells led to strong toxicity in mice within hours, which resulted in enhanced IL-6 levels in the serum and accumulation of poly-ubiquitinated proteins. Furthermore, we linked the observed toxicity to the specific formation of aggregates in the skeletal muscle tissue and the upregulation of both lactate dehydrogenase and creatine kinase in the serum.

Uptake of Plasmodium chabaudi hemozoin drives Kupffer cell death and fuels superinfections

Kupffer cells (KCs) are self-maintained tissue-resident macrophages that line liver sinusoids and play an important role on host defense. It has been demonstrated that upon infection or intense liver inflammation, KCs might be severely depleted and replaced by immature monocytic cells; however, the mechanisms of cell death and the alterations on liver immunity against infections deserves further investigation. We explored the impact of acute Plasmodium infection on KC biology and on the hepatic immune response against secondary infections. Similar to patients, infection with Plasmodium chabaudi induced acute liver damage as determined by serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) elevation. This was associated with accumulation of hemozoin, increased of proinflammatory response and impaired bacterial and viral clearance, which led to pathogen spread to other organs. In line with this, mice infected with Plasmodium had enhanced mortality during secondary infections, which was associated with increased production of mitochondrial superoxide, lipid peroxidation and increased free iron within KCs—hallmarks of cell death by ferroptosis. Therefore, we revealed that accumulation of iron with KCs, triggered by uptake of circulating hemozoin, is a novel mechanism of macrophage depletion and liver inflammation during malaria, providing novel insights on host susceptibility to secondary infections. Malaria can cause severe liver damage, along with depletion of liver macrophages, which can predispose individuals to secondary infections and enhance the chances of death.

COVID-19 in Immunocompromised Children and Adolescents.

COVID-19 in Immunocompromised Children and Adolescents.

Autoreactive CD8+ T cells are restrained by an exhaustion-like program that is maintained by LAG3.

Impaired chronic viral and tumor clearance has been attributed to CD8+ T cell exhaustion, a differentiation state in which T cells have reduced and altered effector function that can be partially reversed upon blockade of inhibitory receptors. The role of the exhaustion program and transcriptional networks that control CD8+ T cell function and fate in autoimmunity is not clear. Here we show that intra-islet CD8+ T cells phenotypically, transcriptionally, epigenetically and metabolically possess features of canonically exhausted T cells, yet maintain important differences. This 'restrained' phenotype can be perturbed and disease accelerated by CD8+ T cell-restricted deletion of the inhibitory receptor lymphocyte activating gene 3 (LAG3). Mechanistically, LAG3-deficient CD8+ T cells have enhanced effector-like functions, trafficking to the islets, and have a diminished exhausted phenotype, highlighting a physiological role for an exhaustion program in limiting autoimmunity and implicating LAG3 as a target for autoimmune therapy.

Serum Level of Anti-Nucleocapsid, but Not Anti-Spike Antibody, Is Associated with Improvement of Long COVID Symptoms.

Background: Long COVID is a condition characterized by long-term sequelae persisting after the typical convalescence period of COVID-19. Previous reports have suggested the role of an unsatisfactory immune response and impaired viral clearance in the pathogenesis of long COVID syndrome. We focused on potential associations between post-vaccination changes of antibody titers and the severity of long COVID symptoms and factors influencing the state of remission observed in patients with long COVID after vaccination. Methods: The severity of long COVID symptoms and serum anti-SARS-CoV-2 spike (S-Ig) and nucleocapsid (NC-Ig) levels were assessed in 107 post-COVID subjects at two time points: at baseline, and 17–24 weeks later. Besides, vaccination status was also assessed. Symptoms were evaluated based on the Chalder fatigue scale (CFQ-11) and visual analogue scale (VAS). Results: Serum level of S-Ig and NC-Ig at baseline were significantly higher in the patients with non-severe fatigue than those with severe fatigue, and this difference remained significant at follow-up in the case of NC-Ig. NC-Ig level above median was as an independent predictor for complete remission at follow-up. The difference in NC-Ig levels in subgroup analyses (severe fatigue vs. non-severe fatigue; complete remission vs. incomplete remission or progression) was found to be significant only in patients who received vaccination. Conclusions: The immune response against the SARS-CoV-2 nucleocapsid may play a more important role than the spike in the course of long-term COVID syndrome.

Dual oxidase 1 promotes antiviral innate immunity

Dual oxidase 1 (DUOX1) is an NADPH oxidase that is highly expre-ssed in respiratory epithelial cells and produces H2O2 in the airway lumen. While a line of prior in vitro observations suggested that DUOX1 works in partnership with an airway peroxidase, lactoperoxidase (LPO), to produce antimicrobial hypothiocyanite (OSCN-) in the airways, the in vivo role of DUOX1 in mammalian organisms has remained unproven to date. Here, we show that Duox1 promotes antiviral innate immunity in vivo. Upon influenza airway challenge, Duox1-/- mice have enhanced mortality, morbidity, and impaired lung viral clearance. Duox1 increases the airway levels of several cytokines (IL-1β, IL-2, CCL1, CCL3, CCL11, CCL19, CCL20, CCL27, CXCL5, and CXCL11), contributes to innate immune cell recruitment, and affects epithelial apoptosis in the airways. In primary human tracheobronchial epithelial cells, OSCN- is generated by LPO using DUOX1-derived H2O2 and inactivates several influenza strains in vitro. We also show that OSCN- diminishes influenza replication and viral RNA synthesis in infected host cells that is inhibited by the H2O2 scavenger catalase. Binding of the influenza virus to host cells and viral entry are both reduced by OSCN- in an H2O2-dependent manner in vitro. OSCN- does not affect the neuraminidase activity or morphology of the influenza virus. Overall, this antiviral function of Duox1 identifies an in vivo role of this gene, defines the steps in the infection cycle targeted by OSCN-, and proposes that boosting this mechanism in vivo can have therapeutic potential in treating viral infections.

Neurologic Manifestations of COVID-19 in Children: Emerging Pathophysiologic Insights.

The COVID-19 pandemic has affected mortality and morbidity across all ages, including children. Neurologic manifestations of coronavirus disease 2019, ranging from headaches to cerebrovascular stroke, may involve the CNS or peripheral nervous system. Neurologic involvement is also noted in the multisystem inflammatory syndrome in children, a pediatric condition that occurs weeks after infection with severe acute respiratory syndrome coronavirus 2, the virus that causes COVID-19. Knowledge about mechanisms of neurologic disease and immunologic response to severe acute respiratory syndrome coronavirus 2 is scarce but rapidly growing. Here, we concisely review experimental and clinical data relevant to pathophysiologic hypotheses regarding neurologic manifestations of coronavirus disease 2019. We highlight important knowledge gaps in differences between adults and children in their response to coronavirus disease 2019.

Intra-islet CD8+ T cells are restrained by an exhaustion program that can be reversed by LAG3 deletion

Abstract CD8+ T cell exhaustion or dysfunction is a differentiation state in which T cells become unresponsive to stimulation and lose effector function1. Impaired chronic viral and tumor clearance has been attributed to CD8+ T cell exhaustion and can be partially reversed upon blockade of inhibitory receptors (IR) such as programmed cell death protein 1 (PD1). Despite detailed analysis of CD8+T cell in tumors and chronic viral infection, the role of the exhaustion program and the transcriptional networks that control CD8+T cell function and fate in autoimmunity are still unknown. Here we show that intra-islet CD8+T cells phenotypically and transcriptionally possess features of exhausted T cells, yet maintain key differences, such as an expanded repertoire of effector mechanisms, that contribute to their persistent pathogenicity in autoimmune diabetes. This dual identity, which we refer to as a ‘divergent’ exhaustion program, can be perturbed substantively by CD8+ T cell-restricted deletion of the IR Lymphocyte Activating Gene 3 (LAG3), causing enhanced effector-like function and pathogenicity. Understanding this divergent exhaustion program and its key mediators will guide future immunotherapeutic interventions by characterizing ways to promote exhaustion in autoimmunity and reversing exhaustion programs in chronic viral infections and tumors.

Tai Chi to Preserve General Health of Elderly during the COVID-19 Pandemic

SARS-CoV-2 virus is more severe in the elderly and contributes to most death cases. This is postulated due to the presence of multiple comorbidities and age-related immunological changes like immunosenescence and inflameaging. Immunesenescence causes impaired viral clearance, while inflameaging causes exaggerated response inappropriate to stimuli that triggers life-threatening cytokine storm. Hence, home-isolation prevents infection among the elderly and this limits their physical activity. Sedentary lifestyle eventually worsens pre-existing chronic disease and increases the risk of acquiring a new one. Tai Chi is one of the exercises recommended for the elderly during home-isolation. This literature review aims to provide information regarding the groups suggested for Tai Chi, its benefits, as an exercise to be practiced by elderly to maintain general health during COVID-19 and adverse effects. Tai Chi is for those aged 50 years and above or individuals with certain chronic, degenerative or psychological conditions. The systemic benefits are reduction in blood pressure, improves lipid profile, reduction in bone loss and musculoskeletal improvements; whereas neurologically, it reduces cortical shrinkage and improves depression, anxiety and insomnia. Moreover, it induces immune-regulation, which leads to enhancement of the immune system and inhibition of age-related chronic inflammatory condition, inflameaging. These may be protective against severe COVID-19 illness yet further studies are warranted. The adverse effect includes minor musculoskeletal pain and aches. In conclusion, Tai Chi is an ideal exercise for the elderly to maintain health during this challenging pandemic. However, the elderly need to be guided for the proper technique to perform this exercise at home.

Obesity as a Risk Factor for Severe COVID-19 and Complications: A Review.

Emerging data suggest that obesity is a major risk factor for the progression of major complications such as acute respiratory distress syndrome (ARDS), cytokine storm and coagulopathy in COVID-19. Understanding the mechanisms underlying the link between obesity and disease severity as a result of SARS-CoV-2 infection is crucial for the development of new therapeutic interventions and preventive measures in this high-risk group. We propose that multiple features of obesity contribute to the prevalence of severe COVID-19 and complications. First, viral entry can be facilitated by the upregulation of viral entry receptors, like angiotensin-converting enzyme 2 (ACE2), among others. Second, obesity-induced chronic inflammation and disruptions of insulin and leptin signaling can result in impaired viral clearance and a disproportionate or hyper-inflammatory response, which together with elevated ferritin levels can be a direct cause for ARDS and cytokine storm. Third, the negative consequences of obesity on blood coagulation can contribute to the progression of thrombus formation and hemorrhage. In this review we first summarize clinical findings on the relationship between obesity and COVID-19 disease severity and then further discuss potential mechanisms that could explain the risk for major complications in patients suffering from obesity.

Hypothesized mechanisms explaining poor prognosis in type 2 diabetes patients with COVID-19: a review.

PurposeEpidemiological data suggest that comorbid patients, mostly those with type 2 diabetes (T2D), are predisposed to poor prognosis in Coronavirus disease 2019 (COVID-19), leading to serious healthcare concerns. The aim of the present manuscript is to review the main relevant mechanisms possibly contributing to worsen the clinical course of COVID-19 in T2D.ResultsPoor glucose control, high glycaemic variability and diabetes-related comorbidities at baseline, particularly cardiovascular diseases and obesity, contribute in worsening the prognosis in the above-mentioned cluster of patients. Moreover, both a lower efficient innate immune system response and cytokine dysregulation predispose patients with T2D to impaired viral clearance and more serious pulmonary and systemic inflammation once the SARS-CoV-2 infection occurred. Inconclusive data are currently available for specifically indicate or contraindicate concurrent medications for managing T2D and its comorbidities in infected patients.ConclusionsT2D individuals should be considered as more vulnerable to COVID-19 than general population, and thus require adequate advices about hygienic tips to protect themselves during the pandemic. A careful management of glucose levels and diabetes-related comorbidities remains essential for avoiding further complications, and patient monitoring during the pandemic should be performed also at distance by means of telemedicine. Further studies are needed to clarify whether medications normally used for managing T2D and its associated comorbidities could have a protective or detrimental effect on COVID-19 clinical course.

Worse progression of COVID-19 in men: Is testosterone a key factor?

BackgroundThe novel severe acute respiratory syndrome coronavirus (SARS‐CoV‐2) disease 2019 (COVID‐19) seems to have a worse clinical course among infected men compared with women, thus highlighting concerns about gender predisposition to serious prognosis. Therefore, androgens, particularly testosterone (T), could be suspected as playing a critical role in driving this excess of risk. However, gonadal function in critically ill men is actually unknown, mainly because serum T concentration is not routinely measured in clinical practice, even more in this clinical context.ObjectiveTo overview on possible mechanisms by which serum T levels could affect the progression of COVID‐19 in men.MethodsAuthors searched PubMed/MEDLINE, Web of Science, EMBASE, Cochrane Library, Google, and institutional websites for medical subject headings terms and free text words referred to “SARS‐CoV‐2,” “COVID‐19,” “testosterone,” “male hypogonadism,” “gender” “immune system,” “obesity,” “thrombosis” until May 19th 2020.ResultsT, co‐regulating the expression of angiotensin‐converting enzyme 2 and transmembrane protease serine 2 in host cells, may facilitate SARS‐CoV‐2 internalization. Instead, low serum T levels may predispose to endothelial dysfunction, thrombosis and defective immune response, leading to both impaired viral clearance and systemic inflammation. Obesity, one of the leading causes of severe prognosis in infected patients, is strictly associated with functional hypogonadism, and may consistently strengthen the aforementioned alterations, ultimately predisposing to serious respiratory and systemic consequences.Discussion and conclusionT in comparison to estrogen may predispose men to a widespread COVID‐19 infection. Low serum levels of T, which should be supposed to characterize the hormonal milieu in seriously ill individuals, may predispose men, especially elderly men, to poor prognosis or death. Further studies are needed to confirm these pathophysiological assumptions and to promptly identify adequate therapeutic strategies.

COVID-19 and MS disease-modifying therapies.

ObjectiveTo address concerns regarding the effect of MS disease-modifying therapies (DMTs) on the expression of coronavirus 2019 (COVID-19).MethodsReview of the current state of knowledge regarding the viral etiology of COVID-19, mechanisms of injury by SARS-CoV-2 infection, and the effect of individual DMTs on the risk of infection and COVID-19 disease expression.ResultsAlthough data are limited, MS DMTs do not obviously increase the risk of acquiring symptomatic SARS-CoV-2 infection. The severe morbidity and mortality of SARS-CoV-2 appear to be largely the consequence of an overly robust immune response rather than the consequence of unchecked viral replication. The effects of specific MS DMTs on the immune response that may increase the risk of impaired viral clearance and their potential counterbalancing beneficial effects on the development of COVID-19–associated acute respiratory distress syndrome are reviewed.ConclusionAlthough there is currently insufficient real-world experience to definitively answer the question of the effect of a specific MS DMT on COVID-19, registries presently in nascent form should provide these answers. This review provides an approach to addressing these concerns while the data are being accumulated. Early insights suggest that the risk of infection and associated morbidity of COVID-19 in this population is little different than that of the population at large.

Bacterial neuraminidase C reverts neuraminidase A and B mediated suppression of anti-influenza immunity and aggravates the disease in influenza with pneumococcal superinfection

Abstract Bacterial superinfection aggravates the disease of influenza virus infection. Streptococcus pneumoniae is a frequently encountered bacterial pathogen. Superinfection with neuraminidase (Nan) C deficient wild type pneumococcus, which expresses NanA and NanB only, suppressed antigen-specific anti-influenza immunity, with impaired viral clearance. There was augmented TGF-β activation in the lung-infiltrating influenza hemagglutinin (HA)-specific CD4+ T cells. Mice suffered from exacerbated disease and died with higher virus loads in the lung. We modified this wild type strain with NanC insertion. This modified strain expresses all neuraminidases A, B and C. Superinfection with this NanC inserted pneumococcus reverted the immune-suppressive effect of the wild type pneumococcus with NanA and NanB only. There were augmented inflammatory cytokines IFN-γ and TNF-α production and suppressed TGF-β activation in the lung-infiltrating influenza HA-specific CD4+ T cells. The pro-inflammatory response enhanced viral clearance. Even the virus eradication is enhanced, the mice actually suffered from even more severe disease. Our results demonstrated the important role of NanC-mediated inflammation in the disease of severe influenza with pneumococcal superinfection.

LAG-3 marks effector to regulatory evolution of Th1 immunity in influenza

Abstract Naïve CD4+ T cells respond in influenza with T-bet expression, a transcription factor up-regulated with Th1 commitment. We report concomitant LAG-3 expression on these Th1 committed cells with evolution into regulatory T cells. LAG-3 expression increases with activation as revealed by CFSE cell division study. Cells with moderate LAG-3 expression produce IFN-γ and contribute to inflammation and disease. They no longer produce IFN-γ with higher LAG-3 expression upon further activation. High LAG-3 cells suppress and decouple effector function from the preserved proliferation of CD8+ T cells. They restrain inflammation with facilitated viral clearance and ameliorate the disease of severe influenza. Foxp-3+CD4+ T cells suppress both effector and proliferative responses with impaired viral clearance and they are less potent in disease amelioration. Principal component analysis of genome-wide expression further confirmed the stepwise evolution from effector to regulatory T cells. Regulatory genes are up-regulated progressively from LAG-3Neg to LAG-3Med and to LAG-3High cells.

Computer Modeling of Clonal Dominance: Memory-Anti-Naïve and Its Curbing by Attrition.

Experimental and computational studies have revealed that T-cell cross-reactivity is a widespread phenomenon that can either be advantageous or detrimental to the host. In particular, detrimental effects can occur whenever the clonal dominance of memory cells is not justified by their infection-clearing capacity. Using an agent-based model of the immune system, we recently predicted the “memory anti-naïve” phenomenon, which occurs when the secondary challenge is similar but not identical to the primary stimulation. In this case, the pre-existing memory cells formed during the primary infection may be rapidly deployed in spite of their low affinity and can actually prevent a potentially higher affinity naïve response from emerging, resulting in impaired viral clearance. This finding allowed us to propose a mechanistic explanation for the concept of “antigenic sin” originally described in the context of the humoral response. However, the fact that antigenic sin is a relatively rare occurrence suggests the existence of evolutionary mechanisms that can mitigate the effect of the memory anti-naïve phenomenon. In this study we use computer modeling to further elucidate clonal dominance and the memory anti-naïve phenomenon, and to investigate a possible mitigating factor called attrition. Attrition has been described in the experimental and computational literature as a combination of competition for space and apoptosis of lymphocytes via type-I interferon in the early stages of a viral infection. This study systematically explores the relationship between clonal dominance and the mechanism of attrition. Our results suggest that attrition can indeed mitigate the memory anti-naïve effect by enabling the emergence of a diverse, higher affinity naïve response against the secondary challenge. In conclusion, modeling attrition allows us to shed light on the nature of clonal interaction and dominance.

β Cell Hypoxia-Inducible Factor-1α Is Required for the Prevention of Type 1 Diabetes

SUMMARYThe development of autoimmune disease type 1 diabetes (T1D) is determined by both genetic background and environmental factors. Environmental triggers include RNA viruses, particularly coxsackie-virus (CV), but how they induceT1D is not understood. Here, we demonstrate that deletion of the transcription factor hypoxia-inducible factor-1α (HIF-1α) from β cells increases the susceptibility of non-obese diabetic (NOD) mice to environmentally triggered T1D from coxsackieviruses and the β cell toxin streptozotocin. Similarly, knockdown of HIF-1α in human islets leads to a poorer response to coxsackievirus infection. Studies in coxsackievirus-infected islets demonstrate that lack of HIF-1α leads to impaired viral clearance, increased viral load, inflammation, pancreatitis, and loss of β cell mass. These findings show an important role for β cells and, specifically, lack of β cell HIF-1α in the development of T1D. These data suggest new strategies for the prevention of T1D.