Evaluation of the new 2.0 version of the Roche SARS-CoV-2 Rapid Antigen Test.

We evaluated the new 2.0 version of the Roche Diagnostics SARS-CoV-2 Rapid Antigen Test (RAT 2.0) for the detection of SARS-CoV-2. Our evaluation material comprised of nasopharyngeal samples of 140 persons positive for SARS-CoV-2 nucleic acid amplification test (NAAT) and of 100 persons negative for SARS-CoV-2 NAAT. The sensitivity limit of the RAT 2.0 was further estimated with the additional selected samples of 27 persons with high NAAT cycle threshold (Ct) value representing low viral load. For the detection of possible cross-reactions in the RAT 2.0, routine respiratory samples positive for influenza A (N = 5), respiratory syncytial virus (RSV) (N = 4), or combined RSV and human coronavirus OC43 (N = 1) were included in the study material. The overall sensitivity of the RAT 2.0 was 92.1% and specificity 100%. When evaluating the samples with NAAT Ct value ≤ 30, the sensitivity was 97.0%. All samples for cross-reactivity testing containing other viruses instead of SARS-CoV-2 remained negative in RAT 2.0. According to our findings, this RAT 2.0 offers a reliable tool for the diagnostics of acute COVID-19 in this pandemic environment.

Evaluation of the Roche-SD Biosensor rapid antigen test: Antigen is not reliable in detecting SARS-CoV-2 at the early stage of infection with respiratory symptoms.

We evaluated a rapid antigen test against SARS-CoV-2 virus (Roche-SD Biosensor; RSDB-RAT) in children and adults with respiratory symptoms compared to those with nonrespiratory symptoms or asymptomatic. Also the performance of RSDB-RAT with respect to the duration of respiratory symptoms was assessed. A viral cross-reactivity panel was included. RSDB-RAT was reliable in detecting SARS-CoV-2 in children and adults if the respiratory symptoms had endured 1 to 7 days. If the respiratory symptoms had lasted less than 1 day, the sensitivity was significantly lower. No cross-reactivity with other respiratory viruses was observed.

Comparison of 2 fully automated tests detecting antibodies against nucleocapsid N and spike S1/S2 proteins in COVID-19.

Automated assays for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in coronavirus disease 2019 (COVID-19) diagnostics have recently come available. We compared the performance of the Elecsys® Anti-SARS-CoV-2 and LIAISON® SARS-CoV-2 S1/S2 IgG tests. The seroconversion panel comprised of 120 samples from 13 hospitalized COVID-19 patients. For the sensitivity and specificity testing, samples from COVID-19 outpatients >15 days after positive nucleic acid amplification test (NAAT) result (n = 35) and serum control samples collected before the COVID-19 era (n = 161) were included in the material. Samples for the detection of possible cross-reactions were also tested. Based on our results, the SARS-CoV-2 antibodies can be quite reliably detected 2 weeks after NAAT positivity and 3 weeks after the symptom onset with both tests. However, since some COVID-19 patients were positive only with Elecsys®, the antibodies should be screened against N-antigen (Elecsys®) and reactive samples confirmed with S antigen (LIAISON®), but both results should be reported. In some COVID-19 patients, the serology can remain negative.

Effect of aging on the transcriptomic changes associated with the expression of the HERV-K (HML-2) provirus at 1q22.

BACKGROUND: The human genome contains remnants of ancient retroviral infections called human endogenous retroviruses (HERV). Their expression is often observed in several diseases of autoimmune or inflammatory nature. However, the exact biological mechanisms induced by HERVs are still poorly understood. We have previously shown that several HERVs of the HERV-K (HML-2) family are strongly transcribed in the peripheral blood mononuclear cells (PBMC) derived from young and old individuals. To examine the potential functional consequences of HERV-K (HML-2) expression, we have now analyzed the correlation of its expression with age-associated changes in the transcriptome using gene set enrichment analysis (GSEA). We focused our analysis on the HERV-K (HML-2) provirus at 1q22, also known as ERVK-7. RESULTS: The genes strongly correlating with the expression of HERV-K (HML-2) provirus at 1q22 expression were found to be almost entirely different in young and old individuals. The number of genes strongly correlating (Pearson correlation coefficient ≥ 0.7) with 1q22 expression was 946 genes in the old and 435 in the young, of which only 41 genes correlated strongly in both. Consequently, the related gene ontology (GO) biological processes were different. In the older individuals, many of the highest correlating processes relate to the function of neutrophils. CONCLUSIONS: The results of this work suggest that the biological processes associated with the expression of HERV-K (HML-2) provirus at 1q22 are different in the blood of young and old individuals. Specifically, a strong association was found in the older individuals between neutrophil activity and the expression of the HERV-K (HML-2) provirus at 1q22. These findings offer insight into potential effects of altered HERV expression in older individuals.

Pregestational overweight and obesity are associated with differences in gut microbiota composition and systemic inflammation in the third trimester.

The obesity epidemic is a global challenge, and the velocity of propagation is high in the population at reproductive age. Overweight and obesity during pregnancy have been associated with high birth weight and an increased risk of childhood obesity, reinforcing the risk of other non-communicable diseases. Obesity involves chronic low-grade systemic inflammation. New biomarkers for early detection of obesity risk are urgently required. The aim of this study was to identify the connection between pregestational BMI (pre-BMI) status and inflammatory biomarkers during the third trimester of pregnancy and their association with intestinal microbiota composition. Fifty-four pregnant women were classified according to pre-pregnancy BMI as normoweight, overweight, or obese. Weight gain, inflammatory biomarkers (hs_CRP, haptoglobin, and suPAR), and microbiota composition were assessed during the third trimester. A significant lower weight gain for obese mothers and a positive correlation between pre-BMI and inflammatory biomarkers were detected (Spearman's correlation). Haptoglobin levels were significantly higher in overweight and obese mothers. Higher Firmicutes levels and a higher ratio Firmicutes/Bacteroidetes were observed in the overweight and obese subjects. High hs_CRP and haptoglobin levels were also correlated with decreased microbiota diversity (Shannon index), whereas haptoglobin and hs_CRP values were correlated with several microbiota components, such as Ruminococcus gnavus and Faecalibacterium, and with specific phyla in the normoweight and overweight mothers; no significant associations with microbiota were found for suPAR. In conclusion, haptoglobin and hs_CRP reflected pregestational BMI status and related microbiota components, but haptoglobin was a better biomarker for microbiota associated with overweight. suPAR was associated with low grade inflammation dependent on pre-pregnancy BMI, but it was not related to deviated microbiota profiles.