Immunosuppressants exert differential effects on pan-coronavirus infection and distinct combinatory antiviral activity with molnupiravir and nirmatrelvir.

BACKGROUND: Immunocompromised populations, such as organ transplant recipients and patients with inflammatory bowel disease (IBD) receiving immunosuppressive/immunomodulatory medications, may be more susceptible to coronavirus infections. However, little is known about how immunosuppressants affect coronavirus replication and their combinational effects with antiviral drugs. OBJECTIVE: This study aims to profile the effects of immunosuppressants and the combination of immunosuppressants with oral antiviral drugs molnupiravir and nirmatrelvir on pan-coronavirus infection in cell and human airway organoids (hAOs) culture models. METHODS: Different coronaviruses (including wild type, delta and omicron variants of SARS-CoV-2, and NL63, 229E and OC43 seasonal coronaviruses) were used in lung cell lines and hAOs models. The effects of immunosuppressants were tested. RESULTS: Dexamethasone and 5-aminosalicylic acid moderately stimulated the replication of different coronaviruses. Mycophenolic acid (MPA), 6-thioguanine (6-TG), tofacitinib and filgotinib treatment dose-dependently inhibited viral replication of all tested coronaviruses in both cell lines and hAOs. The half maximum effective concentration (EC50) of tofacitinib against SARS-CoV-2 was 0.62 µM and the half maximum cytotoxic concentration (CC50) was above 30 µM, which resulted in a selective index (SI) of about 50. The anti-coronavirus effect of the JAK inhibitors tofacitinib and filgotinib is dependent on the inhibition of STAT3 phosphorylation. Combinations of MPA, 6-TG, tofacitinib, and filgotinib with the oral antiviral drugs molnupiravir or nirmatrelvir exerted an additive or synergistic antiviral activity. CONCLUSIONS: Different immunosuppressants have distinct effects on coronavirus replication, with 6-TG, MPA, tofacitinib and filgotinib possessing pan-coronavirus antiviral activity. The combinations of MPA, 6-TG, tofacitinib and filgotinib with antiviral drugs exerted an additive or synergistic antiviral activity. Thus, these findings provide an important reference for optimal management of immunocompromised patients infected with coronaviruses.

Nirmatrelvir exerts distinct antiviral potency against different human coronaviruses.

Nirmatrelvir is the main component of Paxlovid, an oral antiviral drug approved for the treatment of COVID-19 caused by SARS-COV-2 infection. Nirmatrelvir targets the main protease (Mpro), which is substantially conserved among different coronaviruses. Here, our molecular docking analysis indicates comparable affinity of nirmatrelvir binding to the Mpro enzymes of SARS-CoV-2 and three seasonal coronaviruses (OC43, 229E and NL63). However, in cell culture models, we found that nirmatrelvir potently inhibited SARS-CoV-2, OC43 and 229E, but not NL63. The insensitivity of NL63 to nirmatrelvir treatment was demonstrated at both viral replication and infectious titer levels. The antiviral activity of nirmatrelvir against OC43 and 229E was further confirmed in human airway organoids. The combination of nirmatrelvir and molnupiravir exerted differential patterns of antiviral response against OC43 and 229E. These results revealed disparities in the ability of nirmatrelvir to inhibit different coronaviruses, and caution against repurposing of nirmatrelvir as a pan-coronavirus treatment.

Recapitulating infection, thermal sensitivity and antiviral treatment of seasonal coronaviruses in human airway organoids.

BACKGROUND: Human seasonal coronaviruses usually cause mild upper-respiratory tract infection, but severe complications can occur in specific populations. Research into seasonal coronaviruses is limited and robust experimental models are largely lacking. This study aims to establish human airway organoids (hAOs)-based systems for seasonal coronavirus infection and to demonstrate their applications in studying virus-host interactions and therapeutic development. METHODS: The infections of seasonal coronaviruses 229E, OC43 and NL63 in 3D cultured hAOs with undifferentiated or differentiated phenotypes were tested. The kinetics of virus replication and production was profiled at 33 °C and 37 °C. Genome-wide transcriptome analysis by RNA sequencing was performed in hAOs under various conditions. The antiviral activity of molnupiravir and remdesivir, two approved medications for treating COVID19, was tested. FINDINGS: HAOs efficiently support the replication and infectious virus production of seasonal coronaviruses 229E, OC43 and NL63. Interestingly, seasonal coronaviruses replicate much more efficiently at 33 °C compared to 37 °C, resulting in over 10-fold higher levels of viral replication. Genome-wide transcriptomic analyses revealed distinct patterns of infection-triggered host responses at 33 °C compared to 37 °C temperature. Treatment of molnupiravir and remdesivir dose-dependently inhibited the replication of 229E, OC43 and NL63 in hAOs. INTERPRETATION: HAOs are capable of modeling 229E, OC43 and NL63 infections. The intriguing finding that lower temperature resembling that in the upper respiratory tract favors viral replication may help to better understand the pathogenesis and transmissibility of seasonal coronaviruses. HAOs-based innovative models shall facilitate the research and therapeutic development against seasonal coronavirus infections. FUNDING: This research is supported by funding of a VIDI grant (No. 91719300) from the Netherlands Organization for Scientific Research and the Dutch Cancer Society Young Investigator Grant (10140) to Q.P., and the ZonMw COVID project (114025011) from the Netherlands Organization for Health Research and Development to R.R.

Factors Associated With COVID-19 Vaccine Response in Transplant Recipients: A Systematic Review and Meta-analysis.

BACKGROUND: The rapid development and universal access to vaccines represent a milestone in combating the coronavirus disease 2019 (COVID-19) pandemic. However, there are major concerns about vaccine response in immunocompromised populations in particular transplant recipients. In the present study, we aim to comprehensively assess the humoral response to COVID-19 vaccination in both orthotopic organ transplant and allogeneic hematopoietic stem cell transplant recipients. METHODS: We performed a systematic review and meta-analysis of 96 studies that met inclusion criteria. RESULTS: The pooled rates of seroconversion were 49% (95% confidence interval [CI], 43%-55%) in transplant recipients and 99% (95% CI, 99%-99%) in healthy controls after the second dose of vaccine. The pooled rate was 56% (95% CI, 49%-63%) in transplant recipients after the third dose. Immunosuppressive medication is the most prominent risk factor associated with seroconversion failure, but different immunosuppressive regimens are associated with differential outcomes in this respect. Calcineurin inhibitors, steroids, or mycophenolate mofetil/mycophenolic acid are associated with an increased risk of seroconversion failure, whereas azathioprine or mammalian target of rapamycin inhibitors do not. Advanced age, short interval from receiving the vaccine to the time of transplantation, or comorbidities confers a higher risk for seroconversion failure. CONCLUSIONS: Transplant recipients compared with the general population have much lower rates of seroconversion upon receiving COVID-19 vaccines. Immunosuppressants are the most prominent factors associated with seroconversion, although different types may have differential effects.

Association of Current Active Illnesses and Severe Acute Kidney Injury after COVID-19 Vaccines: A Real-World Study.

The administration of COVID-19 vaccines has become increasingly essential to curb the pandemic. However, adverse events of acute kidney injury (AKI) emerge rapidly as the COVID-19 vaccination promotes. To investigate the intervenable risk factors of AKI, we searched the Vaccine Adverse Event Reporting System database and recorded adverse effects after COVID-19 vaccines from Dec 2020 to Jun 2021. We included 1149 AKI cases, of which 627 (54.6%) cases were reported following the Pfizer-BNT COVID-19 vaccine, and 433 (37.7%) were reported after the Moderna vaccine. A univariate analysis revealed that coexisting active illnesses (infections, uncontrolled hypertension, heart failure, etc.) have an unfavorable prognosis, with an increased risk of death (OR 2.35, 95% CI 1.70-3.25, p < 0.001). The other risk factors included older age and past disease histories. An adjusted regression analysis proved that coexisting active illnesses worsen AKI prognosis after COVID-19 vaccination, with a higher mortality risk (OR 2.19, 95% CI 1.48-3.25, p < 0.001). In subgroup analysis, we stratified different variables, and none revealed a significant effect modification on the association between coexisting active illnesses and AKI-associated death after vaccination (p-interaction >0.05). We found that coexisting active illnesses could complicate AKI after vaccines, but the potential causal relationship needed further investigation.

Repurposing dyphylline as a pan-coronavirus antiviral therapy.

Background: In the last two decades, the world has witnessed the emergence of zoonotic corona viruses (CoVs), which cause mild to severe respiratory diseases in humans. Human coronaviruses (HCoVs), mainly from the alpha-CoV and beta-CoV genera, have evolved to be highly pathogenic, such as SARS-CoV-2 causing the COVID-19 pandemic. These coronaviruses carry functional enzymes necessary for the virus life cycle, which represent attractive antiviral targets. Methods & Results: We aimed to therapeutically target the main protease (Mpro) of HCoV-NL63 and HCoV-229E (from alpha-CoV genus) and HCoV-OC43 and SARS-CoV-2 (from beta-CoV genus). Through virtual screening, we identified an FDA-approved drug dyphylline, a xanthine derivate, that binds to the catalytic dyad residues; histidine and cystine of the Mpro structures. Importantly, dyphylline dose-dependently inhibited the viral replication in cell culture models infected with the viruses. Conclusion: Our findings support the repurposing of dyphylline as a pan-coronavirus antiviral agent.

Differing pan-coronavirus antiviral potency of boceprevir and GC376 in vitro despite discordant molecular docking predictions.

Given the structural similarities of the viral enzymes of different coronaviruses (CoVs), we investigated the potency of the anti-SARS-CoV-2 agents boceprevir and GC376 for counteracting seasonal coronavirus infections. In contrast to previous findings that both boceprevir and GC376 are potent inhibitors of the main protease (Mpro) of SARS-CoV-2, we found that GC376 is much more effective than boceprevir in inhibiting SARS-CoV-2 and three seasonal CoVs (NL63, 229E, and OC43) in cell culture models. However, these results are discordant with a molecular docking analysis that suggested comparable affinity of boceprevir and GC376 for the different Mpro enzymes of the four CoVs. Collectively, our results support future development of GC376 but not boceprevir (although it is an FDA-approved antiviral medication) as a pan-coronavirus antiviral agent. Furthermore, we caution against overinterpretation of in silico data when developing antiviral therapies.

Comparative assessment of favipiravir and remdesivir against human coronavirus NL63 in molecular docking and cell culture models.

Human coronavirus NL63 (HCoV-NL63) mainly affects young children and immunocompromised patients, causing morbidity and mortality in a subset of patients. Since no specific treatment is available, this study aims to explore the anti-SARS-CoV-2 agents including favipiravir and remdesivir for treating HCoV-NL63 infection. We first successfully modelled the 3D structure of HCoV-NL63 RNA-dependent RNA polymerase (RdRp) based on the experimentally solved SARS-CoV-2 RdRp structure. Molecular docking indicated that favipiravir has similar binding affinities to SARS-CoV-2 and HCoV-NL63 RdRp with LibDock scores of 75 and 74, respectively. The LibDock scores of remdesivir to SARS-CoV-2 and HCoV-NL63 were 135 and 151, suggesting that remdesivir may have a higher affinity to HCoV-NL63 compared to SARS-CoV-2 RdRp. In cell culture models infected with HCoV-NL63, both favipiravir and remdesivir significantly inhibited viral replication and production of infectious viruses. Overall, remdesivir compared to favipiravir is more potent in inhibiting HCoV-NL63 in cell culture. Importantly, there is no evidence of resistance development upon long-term exposure to remdesivir. Furthermore, combining favipiravir or remdesivir with the clinically used antiviral cytokine interferon-alpha resulted in synergistic effects. These findings provided a proof-of-concept that anti-SARS-CoV-2 drugs, in particular remdesivir, have the potential to be repurposed for treating HCoV-NL63 infection.

Viral polymerase binding and broad-spectrum antiviral activity of molnupiravir against human seasonal coronaviruses.

Endemic seasonal coronaviruses cause morbidity and mortality in a subset of patients, but no specific treatment is available. Molnupiravir is a promising pipeline antiviral drug for treating SARS-CoV-2 infection potentially by targeting RNA-dependent RNA polymerase (RdRp). This study aims to evaluate the potential of repurposing molnupiravir for treating seasonal human coronavirus (HCoV) infections. Molecular docking revealed that the active form of molnupiravir, ß-D-N4-hydroxycytidine (NHC), has similar binding affinity to RdRp of SARS-CoV-2 and seasonal HCoV-NL63, HCoV-OC43 and HCoV-229E. In cell culture models, treatment of molnupiravir effectively inhibited viral replication and production of infectious viruses of the three seasonal coronaviruses. A time-of-drug-addition experiment indicates the specificity of molnupiravir in inhibiting viral components. Furthermore, combining molnupiravir with the protease inhibitor GC376 resulted in enhanced antiviral activity. Our findings highlight that the great potential of repurposing molnupiravir for treating seasonal coronavirus infected patients.

Left-behind children's social adjustment and relationship with parental coping with children's negative emotions during the COVID-19 pandemic in China.

Using data collected from two provinces in China through an online survey, the current study aimed to investigate left-behind children's emotional and academic adjustment during the COVID-19 pandemic in China. The participants included 1780 left-behind (960 boys) and 1500 non-left-behind (811 boys) children in elementary and junior high school with a mean age of 11.23. Self-reported questionnaires concerning children's depression, loneliness, anxiety, and academic adjustment, and parents' coping with children's negative emotions were completed. The results suggested that compared with non-left-behind children, left-behind children's depression and anxiety symptoms were more severe and their academic adjustment was poorer. However, left-behind children had lower levels of loneliness than non-left-behind children. Additionally, supportive coping types, especially emotion-focused and problem-focused reactions, were significantly negatively correlated with children's depression and anxiety. Unsupportive coping types, especially distress and punitive reactions, were significantly positively correlated with children's depression and anxiety symptoms. Moreover, the relationships between punitive reactions and depression, ignoring and loneliness and problem-focused reactions and academic adjustment were significantly stronger in left-behind children. Hence, during the pandemic, left-behind children were still at a disadvantage even with their parents' company. However, parents' coping style towards left-behind children's negative emotions played a significant role in their adjustment.

Systematically comparing COVID-19 with the 2009 influenza pandemic for hospitalized patients.

OBJECTIVES: This study aimed to comprehensively compare the clinical features of hospitalized COVID-19 patients with hospitalized 2009 influenza pandemic patients. METHODS: Medline, Embase, Web of Science, Cochrane CENTRAL, and Google scholar were systematically searched to identify studies related to COVID-19 and the 2009 influenza pandemic. The pooled incidence rates of clinical features were estimated using the DerSimonian-Laird random-effects model with the Freeman-Tukey double arcsine transformation method. RESULTS: The incidence rates of fever, cough, shortness of breath, sore throat, rhinorrhea, myalgia/muscle pain, or vomiting were found to be significantly higher in influenza patients when compared with COVID-19 patients. The incidence rates of comorbidities, including cardiovascular disease/hypertension and diabetes, were significantly higher in COVID-19 compared with influenza patients. In contrast, comorbidities such as asthma, chronic obstructive pulmonary disease, and immunocompromised conditions were significantly more common in influenza compared with COVID-19 patients. Unexpectedly, the estimated rates of intensive care unit admission, treatment with extracorporeal membrane oxygenation, treatment with antibiotics, and fatality were comparable between hospitalized COVID-19 and 2009 influenza pandemic patients. CONCLUSIONS: This study comprehensively estimated the differences and similarities of the clinical features and burdens of hospitalized COVID-19 and 2009 influenza pandemic patients. This information will be important to better understand the current COVID-19 pandemic.