Cyclosporin a inhibits rotavirus replication and restores interferon-beta signaling pathway in vitro and in vivo

Bifidobacterium longum and Chlorella sorokiniana Combination Modulates IFN-γ, IL-10, and SOCS3 in Rotavirus-Infected Cells

Rotavirus is the main cause of acute diarrhea in children up to five years of age. In this regard, probiotics are commonly used to treat or prevent gastroenteritis including viral infections. The anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana, by reducing viral infectivity and improving IFN-type I response, has been previously reported. The present study aimed to study the effect of B. longum and/or C. sorokiniana on modulating the antiviral cellular immune response mediated by IFN-γ, IL-10, SOCS3, STAT1, and STAT2 genes in rotavirus-infected cells. To determine the mRNA relative expression of these genes, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection. In addition, infected cells were treated with B. longum and/or C. sorokiniana. Cellular RNA was purified, used for cDNA synthesis, and amplified by qPCR. Our results demonstrated that the combination of B. longum and C. sorokiniana stimulates the antiviral cellular immune response by upregulating IFN-γ and may block pro-inflammatory cytokines by upregulating IL-10 and SOCS3. The results of our study indicated that B. longum, C. sorokiniana, or their combination improve antiviral cellular immune response and might modulate pro-inflammatory responses.

Culture of Human Rotaviruses in Relevant Models Shows Differences in Culture-Adapted and Nonculture-Adapted Strains

Rotavirus (RV) is the leading cause of acute gastroenteritis (AGE) in children under 5 years old worldwide, and several studies have demonstrated that histo-blood group antigens (HBGAs) play a role in its infection process. In the present study, human stool filtrates from patients diagnosed with RV diarrhea (genotyped as P[8]) were used to infect differentiated Caco-2 cells (dCaco-2) to determine whether such viral strains of clinical origin had the ability to replicate in cell cultures displaying HBGAs. The cell culture-adapted human RV Wa model strain (P[8] genotype) was used as a control. A time-course analysis of infection was conducted in dCaco-2 at 1, 24, 48, 72, and 96 h. The replication of two selected clinical isolates and Wa was further assayed in MA104, undifferentiated Caco-2 (uCaco-2), HT29, and HT29-M6 cells, as well as in monolayers of differentiated human intestinal enteroids (HIEs). The results showed that the culture-adapted Wa strain replicated more efficiently in MA104 cells than other utilized cell types. In contrast, clinical virus isolates replicated more efficiently in dCaco-2 cells and HIEs. Furthermore, through surface plasmon resonance analysis of the interaction between the RV spike protein (VP8*) and its glycan receptor (the H antigen), the V7 RV clinical isolate showed 45 times better affinity compared to VP8* from the Wa strain. These findings support the hypothesis that the differences in virus tropism between clinical virus isolates and RV Wa could be a consequence of the different HBGA contents on the surface of the cell lines employed. dCaco-2, HT29, and HT29M6 cells and HIEs display HBGAs on their surfaces, whereas MA104 and uCaco-2 cells do not. These results indicate the relevance of using non-cell culture-adapted human RV to investigate the replication of rotavirus in relevant infection models.

Bifidobacterium longum and Chlorella sorokiniana Improve the IFN Type I-Mediated Antiviral Response in Rotavirus-Infected Cells

Probiotics are effective to treat or prevent gastrointestinal infections, and microalgae have demonstrated important health-promoting effects and in some cases function as prebiotics. In this regard, the anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana by reducing viral infectivity is well known. However, their effect on immune response against rotavirus has not yet been investigated. Therefore, the aim of this study was to determine the role of Bifidobacterium longum and/or Chlorella sorokiniana in influencing an IFN type I-mediated antiviral response in rotavirus-infected cells. In pre-infection experiments, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection, whereas in post-infection assays, HT-29 cells were treated after infection. The cells' mRNA was then purified to determine the relative expression level of IFN-α, IFN-β, and precursors of interferons such as RIG-I, IRF-3, and IRF-5 by qPCR. We showed that combination of B. longum and C. sorokiniana significantly increased IFN-α levels in pre-infection and IFN-β in post-infection assays, as compared with individual effects. Results indicate that B. longum, C. sorokiniana, or their combination improve cellular antiviral immune response.

Advances in the development of antivirals for rotavirus infection

Rotavirus (RV) causes 200,000 deaths per year and imposes a serious burden to public health and livestock farming worldwide. Currently, rehydration (oral and intravenous) remains the main strategy for the treatment of rotavirus gastroenteritis (RVGE), and no specific drugs are available. This review discusses the viral replication cycle in detail and outlines possible therapeutic approaches including immunotherapy, probiotic-assisted therapy, anti-enteric secretory drugs, Chinese medicine, and natural compounds. We present the latest advances in the field of rotavirus antivirals and highlights the potential use of Chinese medicine and natural compounds as therapeutic agents. This review provides an important reference for rotavirus prevention and treatment.

In Vitro efficacy of cyclosporine a and various antiseptics and antiviral drugs on adenovirus genotype 8, a common cause of epidemic keratoconjunctivitis

PURPOSE

To evaluate the in vitro efficacy of cidofovir, ganciclovir, povidone-iodine, chlorhexidine, and cyclosporine A on adenovirus genotype 8.

METHODS

Conjunctival samples were collected from patients with adenoviral conjunctivitis and cultured in A549 cells. Adenovirus diagnosis was confirmed by RT-PCR. For each drug, the 50% cytotoxic concentration (CC 50 ) was determined. Subsequently, the antiviral activity was tested at concentrations below CC 50, and the 50% inhibitor concentration (IC 50 ) of drugs was determined RESULTS: While the IC 50 of cidofovir against adenovirus genotype 8 was 3.07 ± 0.8 µM, ganciclovir, povidone-iodine, chlorhexidine, and cyclosporine A were not found to be effective against adenovirus genotype 8 at concentrations below the CC 50 value.

CONCLUSIONS

Cidofovir was found effective and the IC 50 value was within the ranges in the literature. Ganciclovir and cyclosporine A were found to be ineffective at doses below the cytotoxic dose, povidone-iodine and chlorhexidine was found to be highly cytotoxic.

Emerging Roles of Cyclophilin A in Regulating Viral Cloaking

Cellular cyclophilins (Cyps) such as cyclophilin A (CypA) have emerged as key players at the virus-host interface. As host factors required for the replication of many unrelated viruses, including human immunodeficiency virus (HIV), hepatitis C virus (HCV) and coronaviruses (CoVs), Cyps are attractive targets for antiviral therapy. However, a clear understanding of how these viruses exploit Cyps to promote their replication has yet to be elucidated. Recent findings suggest that CypA contributes to cloaking of viral replication intermediates, an evasion strategy that prevents detection of viral nucleic acid by innate immune sensors. Furthermore, Cyps are emerging to have roles in regulation of cellular antiviral signaling pathways. Recruitment of Cyps by viral proteins may interfere with their ability to regulate these signaling factors. Consistent with disruption of viral cloaking and innate immune evasion, treatment with Cyp inhibitors such as cyclosporine A (CsA) restores antiviral innate immunity and induces expression of a subset of antiviral genes that restrict viral infection, which may help to explain the broad antiviral spectrum of CsA. In this review, we provide an overview of the roles of CypA in viral cloaking and evasion of innate immunity, focusing on the underlying mechanisms and new perspectives for antiviral therapies.

Current and Future Antiviral Strategies to Tackle Gastrointestinal Viral Infections

Acute gastroenteritis caused by virus has a major impact on public health worldwide in terms of morbidity, mortality, and economic burden. The main culprits are rotaviruses, noroviruses, sapoviruses, astroviruses, and enteric adenoviruses. Currently, there are no antiviral drugs available for the prevention or treatment of viral gastroenteritis. Here, we describe the antivirals that were identified as having in vitro and/or in vivo activity against these viruses, originating from in silico design or library screening, natural sources or being repurposed drugs. We also highlight recent advances in model systems available for this (hard to cultivate) group of viruses, such as organoid technologies, and that will facilitate antiviral studies as well as fill some of current knowledge gaps that hamper the development of highly efficient therapies against gastroenteric viruses.

Advances in the Development of Antiviral Compounds for Rotavirus Infections

Group A rotaviruses (RVAs) are the major cause of severe acute gastroenteritis (AGE) in children under 5 years of age, annually resulting in nearly 130,000 deaths worldwide. Social conditions in developing countries that contribute to decreased oral rehydration and vaccine efficacy and the lack of approved antiviral drugs position RVA as a global health concern. In this minireview, we present an update in the field of antiviral compounds, mainly in relation to the latest findings in RVA virion structure and the viral replication cycle. In turn, we attempt to provide a perspective on the possible treatments for RVA-associated AGE, with special focus on novel approaches, such as those representing broad-spectrum therapeutic options. In this context, the modulation of host factors, lipid droplets, and the viral polymerase, which is highly conserved among AGE-causing viruses, are analyzed as possible drug targets.

Cyclosporine A and IFNγ licencing enhances human mesenchymal stromal cell potency in a humanised mouse model of acute graft versus host disease

Immunosuppressive ability in human MSC donors has been shown to be variable and may be a limiting factor in MSC therapeutic efficacy in vivo. The importance of cytokine activation of mesenchymal stromal cells (MSCs) to facilitate their immunosuppressive function is well established. This study sought to further understand the interactions between MSCs and the commonly used calcineurin inhibitor cyclosporine A (CsA). The existing literature regarding approaches that use MSCs and cyclosporine are conflicting regarding the effect of CsA on MSC potency and function. Here, we clearly demonstrate that when added at the same time as MSCs, CsA negatively affects MSC suppression of T cell proliferation. However, licencing MSCs with IFNγ before addition of CsA protects MSCs from this negative effect. Notably, adding CsA to MSCs after IFNγ pre-stimulation enhances MSC production of IDO. Mechanistically, we identified that CsA reduces SOCS1 expression to facilitate enhanced IDO production in IFNγ pre-stimulated MSCs. Importantly, CsA exposure to IFNγ pre-stimulated MSC before administration, significantly enhanced the potency of MSCs in a human relevant humanised mouse model of acute Graft versus Host Disease. In summary, this study identified a novel licencing strategy to enhance MSC potency in vitro and in vivo.

Cyclophilin inhibitors restrict Middle East respiratory syndrome coronavirus via interferon-λ in vitro and in mice

While severe coronavirus infections, including Middle East respiratory syndrome coronavirus (MERS-CoV), cause lung injury with high mortality rates, protective treatment strategies are not approved for clinical use.

We elucidated the molecular mechanisms by which the cyclophilin inhibitors cyclosporin A (CsA) and alisporivir (ALV) restrict MERS-CoV to validate their suitability as readily available therapy in MERS-CoV infection.

Calu-3 cells and primary human alveolar epithelial cells (hAECs) were infected with MERS-CoV and treated with CsA or ALV or inhibitors targeting cyclophilin inhibitor-regulated molecules including calcineurin, nuclear factor of activated T-cells (NFATs) or mitogen-activated protein kinases. Novel CsA-induced pathways were identified by RNA sequencing and manipulated by gene knockdown or neutralising antibodies. Viral replication was quantified by quantitative real-time PCR and 50% tissue culture infective dose. Data were validated in a murine MERS-CoV infection model.

Both CsA and ALV reduced MERS-CoV titres and viral RNA replication in Calu-3 cells and hAECs, improving epithelial integrity. While neither calcineurin nor NFAT inhibition reduced MERS-CoV propagation, blockade of c-Jun N-terminal kinase diminished infectious viral particle release but not RNA accumulation. Importantly, CsA induced interferon regulatory factor 1 (IRF1), a pronounced type III interferon (IFNλ) response and expression of antiviral genes. Downregulation of IRF1 or IFNλ increased MERS-CoV propagation in the presence of CsA. Importantly, oral application of CsA reduced MERS-CoV replication in vivo, correlating with elevated lung IFNλ levels and improved outcome.

We provide evidence that cyclophilin inhibitors efficiently decrease MERS-CoV replication in vitro and in vivo via upregulation of inflammatory antiviral cell responses, in particular IFNλ. CsA might therefore represent a promising candidate for treating MERS-CoV infection.

The cyclophilin inhibitors cyclosporin A and alisporivir activate host innate immunity by induction of interferon-λ via activation of IRF1 in human lung epithelial cells and in vivo, resulting in a significant inhibition of MERS-CoVhttps://bit.ly/37gzIBH

Macleaya cordata extracts exert antiviral effects in newborn mice with rotavirus-induced diarrhea via inhibiting the JAK2/STAT3 signaling pathway

Accumulating evidence demonstrates that Macleaya cordata extract exerts antiviral and anti-inflammatory effects in various diseases. The present study aimed to investigate the potential effects of M. cordata on rotavirus SA11-induced diarrhea in mice. Diarrhea severity, levels of inflammatory cytokines, histological changes in the small intestine and the underlying mechanisms were evaluated in rotavirus-stimulated mice treated with 1, 2 and 4 mg/kg/day M. cordata or 4 mg/kg/day ribavirin (positive control). M. cordata treatment effectively ameliorated rotavirus-induced diarrhea in a dose-dependent manner by decreasing viral RNA levels. In addition, M. cordata reduced the release of pro-inflammatory cytokines including migration inhibitory factor, interleukin (IL)-8, IL-β, interferon-γ and tumor necrosis factor-α, and elevated the secretion of the anti-inflammatory cytokine IL-10 following rotavirus infection. M. cordata inhibited intestinal epithelial cell apoptosis and improved intestinal inflammation after rotavirus infection. The study also revealed that M. cordata exerted antiviral and anti-inflammatory effects on rotavirus-induced diarrhea by suppressing the Janus kinase 2 (JAK2)/STAT3 pathway, as reflected by decreased protein expression of phosphorylated (p)-JAK2 and p-STAT3. Overall, M. cordata effectively inhibited the inflammation caused by rotavirus, which was closely associated with the suppression of JAK2/STAT3 phosphorylation. These data suggested that M. cordata may be applied as a treatment for rotavirus-induced diarrhea.

The Antiviral Properties of Cyclosporine. Focus on Coronavirus, Hepatitis C Virus, Influenza Virus, and Human Immunodeficiency Virus Infections

This review updates current knowledge regarding the risk of viral infections, including COVID-19, in patients treated with cyclosporine. We also shortly refer to bacterial infections and parasitic infestations in patients treated with cyclosporin. Cyclosporine is an immunosuppressive drug, which is widely used in medicine, including in the treatment of autoimmune skin diseases in dermatology, rheumatology, ophthalmology and nephrology, and in organ transplantation. A usual concern associated with immunosuppressive treatment is the potential risk of infections. Interestingly, several data indicate a relatively low risk of infections, especially viral infections, in patients receiving cyclosporine. It was shown that cyclosporine exerts an inhibitory effect on the replication of some viruses, or may have a potentially beneficial effect on the disease course in infections. These include hepatitis C, influenza virus, rotavirus, human immunodeficiency virus and coronavirus infections. Available data indicate that cyclosporine may have a beneficial effect on COVID-19, which is caused by the coronavirus SARS-COV2.

Kisspeptin/GPR54 signaling restricts antiviral innate immune response through regulating calcineurin phosphatase activity

G protein-coupled receptor 54 (GPR54), the key receptor for the neuropeptide hormone kisspeptin, plays essential roles in regulating puberty development and cancer metastasis. However, its role in the antiviral innate immune response is unknown. We report that virus-induced type I interferon (IFN-I) production was significantly enhanced in Gpr54-deficient cells and mice and resulted in restricted viral replication. We found a marked increase of kisspeptin in mouse serum during viral infection, which, in turn, impaired IFN-I production and antiviral immunity through the GPR54/calcineurin axis. Mechanistically, kisspeptin/GPR54 signaling recruited calcineurin and increased its phosphatase activity to dephosphorylate and deactivate TANK [tumor necrosis factor receptor-associated factor (TRAF) family member-associated NF-κB activator]-binding kinase 1 (TBK1) in a Ca²⁺-dependent manner. Thus, our data reveal a kisspeptin/GPR54/calcineurin-mediated immune evasion pathway exploited by virus through the negative feedback loop of TBK1 signaling. These findings also provide insights into the function and cross-talk of kisspeptin, a known neuropeptide hormone, in antiviral innate immune response.

Effect of interferon alpha and cyclosporine treatment separately and in combination on Middle East Respiratory Syndrome Coronavirus (MERS-CoV) replication in a human in-vitro and ex-vivo culture model

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) has emerged as a coronavirus infection of humans in the past 5 years. Though confined to certain geographical regions of the world, infection has been associated with a case fatality rate of 35%, and this mortality may be higher in ventilated patients. As there are few readily available animal models that accurately mimic human disease, it has been a challenge to ethically determine what optimum treatment strategies can be used for this disease. We used in-vitro and human ex-vivo explant cultures to investigate the effect of two immunomodulatory agents, interferon alpha and cyclosporine, singly and in combination, on MERS-CoV replication. In both culture systems the combined treatment was more effective than either agent used alone in reducing MERS-CoV replication. PCR SuperArray analysis showed that the reduction of virus replication was associated with a greater induction of interferon stimulated genes. As these therapeutic agents are already licensed for clinical use, it may be relevant to investigate their use for therapy of human MERS-CoV infection.

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The effect of interferon-α and/or cyclosporine on MERS-CoV replication was evaluated with a human ex-vivo culture model.

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All treatments were able to reduce MERS-CoV replication.

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The combined treatment was more effective than either agent used alone in reducing MERS-CoV replication.

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The effect of the combined treatment group was associated with a greater induction of interferon stimulated genes.

Mycophenolic acid potently inhibits rotavirus infection with a high barrier to resistance development

Rotavirus infection has emerged as an important cause of complications in organ transplantation recipients. Immunosuppressants used to prevent alloreactivity can also interfere with virus infection, but the direct effects of the specific type of immunosuppressants on rotavirus infection are still unclear. Here we profiled the effects of different immunosuppressants on rotavirus using a 2D culture model of Caco2 human intestinal cell line and a 3D model of human primary intestinal organoids inoculated with laboratory and patient-derived rotavirus strains. We found that the responsiveness of rotavirus to Cyclosporine A treatment was moderate and strictly regulated in an opposite direction by its cellular targets cyclophilin A and B. Treatment with mycophenolic acid (MPA) resulted in a 99% inhibition of viral RNA production at the clinically relevant concentration (10 μg/ml) in Caco2 cells. This effect was further confirmed in organoids. Importantly, continuous treatment with MPA for 30 passages did not attenuate its antiviral potency, indicating a high barrier to drug resistance development. Mechanistically, the antiviral effects of MPA act via inhibiting the IMPDH enzyme and resulting in guanosine nucleotide depletion. Thus for transplantation patients at risk for rotavirus infection, the choice of MPA as an immunosuppressive agent appears rational.

Antiviral effects of Lactobacillus ruminis SPM0211 and Bifidobacterium longum SPM1205 and SPM1206 on rotavirus-infected Caco-2 cells and a neonatal mouse model

Rotavirus is worldwide cause of severe gastroenteritis including severe diarrhea and fatal dehydration in infants and young children. There is an available vaccination program for preventing rotavirus infection, but it has limits and restrictions. Probiotics therapy could be an alternative method of antiviral prevention and modulation against rotavirus infection. In this study, we screened the antiviral activity of probiotic bacteria such as 3 Lactobacillus spp. and 14 Bifidobacterium spp. isolated from young Korean. Three of the bacteria, Lactobacillus ruminis SPM0211, Bifidobacterium longum SPM1205, and SPM1206, inhibited human strain Wa rotavirus infection in Caco-2 cells. Furthermore, these bacterial strains inhibited rotavirus replication in a rotavirus-infected neonatal mouse model. To clarify the mechanism of inhibition, we investigated gene expression of Interferon (IFN)-signaling components and IFN-inducible antiviral effectors. All 3 probiotics increased IFN-α and IFN-β levels compared with the control. Gene expression of IFNsignaling components and IFN-inducible antiviral effectors also increased. Overall, these results indicate that L. ruminis SPM0211, B. longum SPM1205 and 1206 efficiently inhibit rotavirus replication in vitro and in vivo. Especially, the antiviral effect of Lactobacillus ruminis SPM0211 is worthy of notice. This is the first report of L. ruminis with antiviral activity. Anti-rotaviral effects of the 3 probiotics are likely due to their modulation of the immune response through promoting type I IFNs, which are key regulators in IFN signaling pathway.

Rotavirus in organ transplantation: drug-virus-host interactions

Although rotavirus is usually recognized as the most common etiology of diarrhea in young children, it can in fact cause severe diseases in organ transplantation recipients irrespective of pediatric or adult patients. This comprehensive literature analysis revealed 200 cases of rotavirus infection with 8 related deaths in the setting of organ transplantation been recorded. Based on published cohort studies, an average incidence of 3% (187 infections out of 6176 organ recipients) was estimated. Rotavirus infection often causes severe gastroenteritis complications and occasionally contributes to acute cellular rejection in these patients. Immunosuppressive agents, universally used after organ transplantation to prevent organ rejection, conceivably play an important role in such a severe pathogenesis. Interestingly, rotavirus can in turn affect the absorption and metabolism of particular immunosuppressive medications via several distinct mechanisms. Even though rotaviral enteritis is self-limiting in general, infected transplantation patients are usually treated with intensive care, rehydration and replacement of nutrition, as well as applying preventive strategies. This article aims to properly assess the clinical impact of rotavirus infection in the setting of organ transplantation and to disseminate the interactions among the virus, host and immunosuppressive medications.

Antiviral effects of cyclosporine A in neonatal mice with rotavirus-induced diarrhea

OBJECTIVES

Because rotavirus gastroenteritis is associated with high morbidity and mortality especially in developing countries, it is necessary to develop antirotavirus drugs for the treatment of rotavirus infection. Previous studies have demonstrated that cyclosporin A (CsA) has antiviral properties against rotavirus. Its effect has not yet been evaluated against rotavirus diarrheal disease. The aim of this study was to assess the anti-rotavirus efficacy of CsA in neonatal mice after induction of rotavirus diarrhea.

METHODS

Suckling mice were inoculated with murine rotavirus. On the onset of diarrhea, mice were given different concentrations of CsA. To evaluate the effects of CsA on reduction of rotavirus diarrhea, diarrhea score, fecal virus shedding, and pathological lesion change in the small intestine, messenger RNA (mRNA) expression levels in the small intestine and spleen of mice were measured for type I interferon (IFN-α and IFN-β), inflammation-related cytokines (interleukin [IL]-8, IL-10, IFN-γ, and tumor necrosis factor-α), and inflammatory signaling pathways (p38, c-Jun N-terminal kinase, activator protein-1, and nuclear factor-kappa B).

RESULTS

Among virus-inoculated and CsA-treated groups, a dose of 5 mg · kg⁻¹ · day⁻¹ of CsA inhibited diarrhea and improved fecal virus shedding and intestinal lesion changes. IFN-β mRNA expression was significantly increased in rotavirus-induced diarrhea mice treated with 5 mg · kg⁻¹ · day⁻¹ of CsA, whereas the mRNA expression levels of inflammation-related cytokines (IL-8, IL-10, IFN-γ, and tumor necrosis factor-α) and inflammatory signaling pathways (p38, c-Jun N-terminal kinase, activator protein-1, and nuclear factor-kappa B) were markedly decreased. Antiviral effects of CsA were dose dependent.

CONCLUSIONS

CsA can inhibit rotavirus infection in neonatal mice through its antiviral properties. The mechanism for this may be through CsA suppression of inflammation by viral inhibition in animal models.

Potential viral pathogenic mechanism in human type 1 diabetes

In type 1 diabetes, as a result of as yet unknown triggering events, auto-aggressive CD8(+) T cells, together with a significant number of other inflammatory cells, including CD8(+) T lymphocytes with unknown specificity, infiltrate the pancreas, leading to insulitis and destruction of the insulin-producing beta cells. Type 1 diabetes is a multifactorial disease caused by an interactive combination of genetic and environmental factors. Viruses are major environmental candidates with known potential effects on specific key points in the pathogenesis of type 1 diabetes and recent findings seem to confirm this presumption. However, we still lack well-grounded mechanistic explanations for how exactly viruses may influence type 1 diabetes aetiology. In this review we provide a summary of experimentally defined viral mechanisms potentially involved in the ontology of type 1 diabetes and discuss some novel hypotheses of how viruses may affect the initiation and natural history of the disease.