Cysteamine exerts in vitro antiviral activity against the SARS-CoV-2 Delta and Omicron variants

The novel SARS-CoV-2 variants of concern (VOC) represent a considerable global alarm because their mutations are known to affect transmissibility and cause immune escape. While preventing severe disease and deaths, the available vaccines do not avoid infection; therefore, COVID-19 disease management still requires effective therapies. We have recently reported that the aminothiol cysteamine, a drug already applied to humans, exerts direct antiviral activity against SARS-CoV-2 and has in vitro immunomodulatory effect. To evaluate whether this compound exerts antiviral effects also against SARS-CoV-2 variants, we performed different infected cell-based assays using Wild type, Delta, or Omicron VOC. We found that cysteamine significantly reduces the cytopathic effect induced by SARS-CoV-2 Wild type strain and Delta variant in Vero E6 cells. On the other hand, cysteamine had no effects on the survival of cells infected with the Omicron variant, due to the lack of cytotoxicity on Vero E6 cells, at least when infected at MOI = 0.001 for 72 h. Moreover, cysteamine significantly reduced the production of Wild type, Delta, and Omicron variants as measured by the virus released in the culture media (Vero E6 and Calu-3 cells) and by transmission electron microscopy analysis (Vero E6 cells). Notably, cysteamine is more effective in inhibiting the Omicron rather than Delta or Wild type viruses, with an 80% inhibition of Omicron production compared to 40% of Wild type and Delta variant. Overall, our findings demonstrate that cysteamine exerts direct antiviral actions against SARS-CoV-2 Delta and Omicron variants, in addition to the Wild type virus. Our data further demonstrate that cysteamine is a good candidate as repurposing drug for the treatment of SARS-CoV-2 infection for the present and, likely, the future VOC and, therefore, it would be important to investigate its clinical relevance in randomized clinical trials

Upper Gastrointestinal Perforations: A Possible Danger of Antibiotic Overuse

BACKGROUND: The role of changes in gut microflora on upper gastrointestinal (UGI) perforations is not known. We conducted a retrospective case-control study to examine the relationship between antibiotic exposure-a proxy for microbiome modulation-and UGI perforations in a national sample. METHODS: We queried a 5% random sample of Medicare (2009-2013) to identify patients \u3e /= 65 years old hospitalized with UGI (stomach or small intestine) perforations using International Classification of Diseases diagnosis codes. Cases with UGI perforations were matched with 4 controls, each based on age and sex. Exposure to outpatient antibiotics (0-30, 31-60, 61-90 days) prior to case patients\u27 index hospitalization admission data was determined with Part D claims. Univariate and multivariable regression analyses were performed to evaluate the effect of antibiotic exposure on UGI perforation. RESULTS: Overall, 504 cases and 2016 matched controls were identified. Compared to controls, more cases had antibiotic exposure 0-30 days (19% vs. 3%, p \u3c 0.001) and 31-60 days (5% vs. 2%, p \u3c 0.001) prior to admission. In adjusted analyses, antibiotic exposure 0-30 days prior to admission was associated with 6.8 increased odds of an UGI perforation (95% CI 4.8, 9.8); 31-60 days was associated with 1.9 increased odds (95% CI 1.1, 3.3); and 61-90 days was associated with 3.7 increased odds (95% CI 2.0, 6.9). CONCLUSIONS: Recent outpatient antibiotic use, in particular in the preceding 30 days, is associated with UGI perforation among Medicare beneficiaries. Exposure to antibiotics, one of the most modifiable determinants of the microbiome, should be minimized in the outpatient setting

External quality assessment of SARS-CoV-2 serology in European expert laboratories, April 2021

Background: Countries worldwide are focusing to mitigate the ongoing SARS-CoV-2 pandemic by employing public health measures. Laboratories have a key role in the control of SARS- CoV-2 transmission. Serology for SARS-CoV-2 is of critical importance to support diagnosis, define the epidemiological framework and evaluate immune responses to natural infection and vaccine administration. Aim: The aim of this study was the assessment of the actual capability among laboratories involved in sero-epidemiological studies on COVID-19 in EU/EEA and EU enlargement countries to detect SARS-CoV-2 antibodies through an external quality assessment ( EQA) based on proficiency testing. Methods: The EQA panels were composed of eight different, pooled human serum samples (all collected in 2020 before the vaccine roll-out), addressing sensitivity and specificity of detection. The panels and two EU human SARS- CoV-2 serological standards were sent to 56 laboratories in 30 countries. Results: The overall performance of laboratories within this EQA indicated a robust ability to establish past SARS-CoV-2 infections via detection of anti-SARS- CoV-2 antibodies, with 53 of 55 laboratories using at least one test that characterised all EQA samples correctly. IgM-specific test methods provided most incorrect sample characterisations (24/208), while test methods detecting total immunoglobulin (0/119) and neutralising antibodies (2/230) performed the best. The semiquantitative assays used by the EQA participants also showed a robust performance in relation to the standards. Conclusion: Our EQA showed a high capability across European reference laboratories for reliable diagnostics for SARS-CoV-2 antibody responses. Serological tests that provide robust and reliable detection of anti SARS- CoV-2 antibodies are available.Molecular basis of virus replication, viral pathogenesis and antiviral strategie

External quality assessment of SARS-CoV-2 serology in European expert laboratories, April 2021

Background: Countries worldwide are focusing to mitigate the ongoing SARS-CoV-2 pandemic by employing public health measures. Laboratories have a key role in the control of SARS- CoV-2 transmission. Serology for SARS-CoV-2 is of critical importance to support diagnosis, define the epidemiological framework and evaluate immune responses to natural infection and vaccine administration. Aim: The aim of this study was the assessment of the actual capability among laboratories involved in sero-epidemiological studies on COVID-19 in EU/EEA and EU enlargement countries to detect SARS-CoV-2 antibodies through an external quality assessment ( EQA) based on proficiency testing. Methods: The EQA panels were composed of eight different, pooled human serum samples (all collected in 2020 before the vaccine roll-out), addressing sensitivity and specificity of detection. The panels and two EU human SARS- CoV-2 serological standards were sent to 56 laboratories in 30 countries. Results: The overall performance of laboratories within this EQA indicated a robust ability to establish past SARS-CoV-2 infections via detection of anti-SARS- CoV-2 antibodies, with 53 of 55 laboratories using at least one test that characterised all EQA samples correctly. IgM-specific test methods provided most incorrect sample characterisations (24/208), while test methods detecting total immunoglobulin (0/119) and neutralising antibodies (2/230) performed the best. The semiquantitative assays used by the EQA participants also showed a robust performance in relation to the standards. Conclusion: Our EQA showed a high capability across European reference laboratories for reliable diagnostics for SARS-CoV-2 antibody responses. Serological tests that provide robust and reliable detection of anti SARS- CoV-2 antibodies are available

Retention of Neutralizing Response against SARS-CoV-2 Omicron Variant in Sputnik V-Vaccinated Individuals

The new Omicron variant of SARS-CoV-2, first identified in November 2021, is rapidly spreading all around the world. Omicron has become the dominant variant of SARS-CoV-2. There are many ongoing studies evaluating the effectiveness of existing vaccines. Studies on the neutralizing activity of vaccinated sera against the Omicron variant are currently being carried out in many laboratories. In this study, we have shown the neutralizing activity of sera against the SARS-CoV-2 Omicron variant compared to the reference Wuhan D614G variant in individuals vaccinated with two doses of Sputnik V up to 6 months after vaccination and in individuals who experienced SARS-CoV-2 infection either before or after vaccination. As a control to our study we also measured neutralizing antibody titers in individuals vaccinated with two doses of BNT162b2. The decrease in NtAb titers to the Omicron variant was 8.1-fold for the group of Sputnik V-vaccinated individuals. When the samples were stratified for the time period after vaccination, a 7.6-fold or 8.8-fold decrease in NtAb titers was noticed after up to 3 and 3-to-6 months after vaccination. We observed a 6.7- and 5-fold decrease in Sputnik V-vaccinated individuals experiencing asymptomatic or symptomatic infection, respectively. These results highlight the observation that the decrease in NtAb to the SARS-CoV-2 Omicron variant compared to the Wuhan variant occurs for different COVID-19 vaccines in use, with some showing no neutralization at all, confirming the necessity of a third booster vaccination