Search

Serological testing for anti‐severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) antibodies is used to detect ongoing or past SARS‐CoV‐2 infections. To study the kinetics of anti‐SARS‐CoV‐2 antibodies and to assess the diagnostic performances of eight serological assays, we used 129 serum samples collected on known days post symptom onset (dpso) from 42 patients with polymerase chain reaction‐confirmed coronavirus disease 2019 (COVID‐19) and 54 serum samples from healthy blood donors, and children infected with seasonal coronaviruses. The sera were analyzed for the presence of immunoglobulin G (IgG), immunoglobulin M (IgM), and immunoglobulin A (IgA) antibodies using indirect immunofluorescence testing (IIFT) based on SARS‐CoV‐2‐infected cells. They were further tested for antibodies against the S1 domain of the SARS‐CoV‐2 spike protein (IgG, IgA) and against the viral nucleocapsid protein (IgG, IgM) using enzyme‐linked immunosorbent assays. The assay specificities were 94.4%–100%. The sensitivities varied largely between assays, reflecting their respective purposes. The sensitivities of IgA and IgM assays were the highest between 11 and 20 dpso, whereas the sensitivities of IgG assays peaked between 20 and 60 dpso. IIFT showed the highest sensitivities due to the use of the whole SARS‐CoV‐2 as substrate and provided information on whether or not the individual has been infected with SARS‐CoV‐2. Enzyme‐linked immunosorbent assays provided further information about both the prevalence and concentration of specific antibodies against selected antigens of SARS‐CoV‐2. Highlights: Sensitivities varied largely between assays at 94.4‐100% specificity.Assay sensitivities peaked 11‐20 dpso for IgA and IgM, and 20‐60 dpso for IgG.IIFT showed highest sensitivities due to whole virus substrate.ELISAs inform on the prevalence and concentration ofspecific antibodies against selected SARS‐CoV‐2 antigens. [ABSTRACT FROM AUTHOR]

Background: Since the beginning of 2020 the SARS-CoV-2 virus has spread to nearly every country in the world. The mainly airborne pathogen has led to large numbers of deaths, principally in elderly and vulnerable segments of the population. Protective vaccines have recently become available, but it is not yet clear whether and when population-wide immunity will be achieved. The existence of evidence for the protective effect of masks covering the mouth and nose is a topic of public debate. Methods: A selective literature search was carried out in PubMed. Data from the German Robert Koch Institute and the Centers for Disease Control and Prevention were also taken into account. Results: When talking, as many as 20 000 droplets ranging in size from 20 to 500 µM are released every second. According to PCR tests, the amount of virus exhaled is highest immediately before the onset of symptoms. No randomized trials have been conducted on the effect of masks covering the mouth and nose. A metaanalysis of 29 studies on infection with SARS-CoV-2, SARS, or MERS revealed that type N-95 masks (corresponding approximately to FFP-2), surgical masks, or similar multilayer cotton masks can greatly reduce the infection risk for the wearers (RR 0.34 [0.26; 0.45], with moderate heterogeneity [I2 = 48%]). Model experiments and case reports suggest that masks covering the mouth and nose afford considerable protection against transmission of SARS-CoV-2 and other airborne diseases by reducing release of and exposure to potentially infectious droplets; in addition, infections that do occur take a milder course. A limitation of the studies analyzed is that in most cases, this effect cannot be viewed in isolation from the protective impact of other measures (distancing, hygiene precautions). Conclusion: It can plausibly be assumed that consistent use of masks covering the mouth and nose can play an important role in containing the spread of SARSCoV- 2. [ABSTRACT FROM AUTHOR]

Abstract: Apoptosis of cardiomyocytes and vascular endothelial cells has been shown to contribute to disease progression in coronary atherosclerosis, in myocardial infarction and in ischemia-reperfusion injury. Sera were obtained from 13 patients with acute ST elevation myocardial infarction and successful primary percutaneous coronary intervention. Human umbilical venous endothelial cells (HUVECs) were incubated with sera from these patients with or without addition of neutrophil granulocytes. TUNEL staining was performed, and apoptotic cells were quantified with immunofluorescence microscopy. To reduce apoptotic damage, ascorbic acid, vitamin E, ulinastatin, or activated protein C were added to patients'' sera, with or without neutrophils, before incubation with endothelial cells. Incubation of endothelial cells with sera from patients increased the apoptosis rate significantly, compared to sera from 7 healthy controls (p <0.001). Co-incubation of endothelial cells with patients'' sera and neutrophils led to a further significant increase of apoptosis. The addition of ascorbic acid, vitamin E, or activated protein C significantly decreased apoptosis rates of endothelial cells in the presence of neutrophils in vitro. Antiapoptotic strategies may be relevant for the therapy of acute coronary syndromes, since elevated leukocyte counts have been shown to be associated with increased morbidity and mortality in coronary heart disease. [Copyright &y& Elsevier]

GLO:OCQ/01oct21:jmv27267-gra-0001.jpg PHOTO (COLOR): . gl Footnotes 1 Christina Deschermeier and Katja Steinhagen contributed equally to this study. B Front Cover Caption b : The cover image is based on the Research Article I Longitudinal detection of SARS-CoV-2-specific antibody responses with different serological methods i by Petra Emmerich et al., https://doi.org/10.1002/jmv.27113. [Extracted from the article]

PURPOSE: Hemostatic alterations and elevated tumor necrosis factor/cachectin (TNFα) serum levels may contribute to the pathogenesis of organ complications in human Plasmodium falciparum malaria. Therefore, we examined whether altered protein C (PC) and thrombin-antithrombin III (TAT) plasma levels correlated with TNFα serum concentrations, parasitemia, and the clinical course of human P. falciparum malaria. PATIENTS AND METHODS: Forty-seven patients with P. falciparum malaria were evaluated prospectively before and during antiparasitic therapy. TNFα serum levels were determined by immunoradiometric assay, PC and TAT plasma antigen by enzyme-linked immunosorbent assay, and PC and PC inhibitor-1 (PCI-1) activity levels by functional tests. Cultured endothelial cells were incubated with serum from four patients with malaria and from healthy control subjects and then assayed for procoagulant activity. Northern blot hybridization was used to detect tissue factor mRNA. RESULTS: In vivo, TNFα serum concentrations were elevated (median: 38.6 pg/mL; n = 47) while plasma levels of PC (antigen 55.4%; activity 39.0%; n = 47) and PCI-1 (0.56 U/L) were decreased in almost all patients before antiparasitic treatment. At the same time, TAT concentrations were high. These alterations correlated significantly (p < 0.01) beth with the severity of the disease (as defined by organ impairment) and with the number of circulating parasitized erythrocytes. Low PCI-1 activity correlated with low PC activity (p < 0.001) and antigen (p < 0.05) levels. The plasma level of coagulation factor IX, another vitamin K-dependent protein, was not significantly changed. In vitro, incubation of endothelial cells with patient serum (severe P. falciparum malaria) increased both endothelial cell procoagulant activity and cytoplasmic tissue factor mRNA levels. CONCLUSION: Elevated levels of TNFα and TAT, decreased plasma levels of anticoagulant PC, and the induction of... [ABSTRACT FROM AUTHOR]