Antigenic cartography using variant-specific hamster sera reveals substantial antigenic variation among Omicron subvariants.

Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) has developed substantial antigenic variability. As the majority of the population now has pre-existing immunity due to infection or vaccination, the use of experimentally generated animal immune sera can be valuable for measuring antigenic differences between virus variants. Here, we immunized Syrian hamsters by two successive infections with one of nine SARS-CoV-2 variants.

Non-cross-reactive epitopes dominate the humoral immune response to COVID-19 vaccination - kinetics of plasma antibodies, plasmablasts and memory B cells.

Introduction: COVID-19 vaccines are highly effective in inducing protective immunity. While the serum antibody response to COVID-19 vaccination has been studied in depth, our knowledge of the underlying plasmablast and memory B cell (Bmem) responses is still incomplete. Here, we determined the antibody and B cell response to COVID-19 vaccination in a naïve population and contrasted it with the response to a single influenza vaccination in a primed cohort.

SARS-CoV-2 rapid antigen test sensitivity and viral load in newly symptomatic hospital employees in Berlin, Germany, December, 2020 to February, 2022: an observational study.

Background: Evolving SARS-CoV-2 variants and changing levels of pre-existing immunity require re-evaluation of antigen-detecting rapid diagnostic test (Ag-RDT) performance. We investigated possible associations between Ag-RDT sensitivity and various potential influencing factors, such as immunisation status and viral variant, in symptomatic hospital employees.

Methods: In this observational study, RT-PCR, Ag-RDT, and symptom-specific data were collected at three SARS-CoV-2 test centres for employees of the Charité-Universitätsmedizin Berlin hospital (Berlin, Germany).

and effects of root extract EPs 7630 and selected constituents against SARS-CoV-2 B.1, Delta AY.4/AY.117 and Omicron BA.2.

The occurrence of immune-evasive SARS-CoV-2 strains emphasizes the importance to search for broad-acting antiviral compounds. Our previous study showed that root extract EPs 7630 has combined antiviral and immunomodulatory properties in SARS-CoV-2-infected human lung cells. Here we assessed effects of EPs 7630 in SARS-CoV-2-infected hamsters, and investigated properties of EPs 7630 and its functionally relevant constituents in context of phenotypically distinct SARS-CoV-2 variants.

Magnipore: Prediction of differential single nucleotide changes in the Oxford Nanopore Technologies sequencing signal of SARS-CoV-2 samples.

Oxford Nanopore Technologies (ONT) allows direct sequencing of ribonucleic acids (RNA) and, in addition, detection of possible RNA modifications due to deviations from the expected ONT signal. The software available so far for this purpose can only detect a small number of modifications. Alternatively, two samples can be compared for different RNA modifications.

Humoral immune responses remain quantitatively impaired but improve qualitatively in anti-CD20-treated patients with multiple sclerosis after three or four COVID-19 vaccinations.

Objective: To analyze anti-SARS-CoV-2-S1-IgG levels, avidity, Omicron BA.2 variant neutralizing capacity, and SARS-CoV-2-specific T cells in anti-CD20-treated patients with multiple sclerosis (aCD20pwMS) after two, three, or four COVID-19 vaccinations.

Results: Frequencies of aCD20pwMS with detectable SARS-CoV-2-S1-IgG increased moderately between two (31/61 (51%)), three (31/57 (54%)), and four (17/26 (65%)) vaccinations.

Preclinical safety and efficacy of a therapeutic antibody that targets SARS-CoV-2 at the sotrovimab face but is escaped by Omicron.

The recurrent emerging of novel viral variants of concern (VOCs) with evasion of preexisting antibody immunity upholds severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) case numbers and maintains a persistent demand for updated therapies. We selected the patient-derived antibody CV38-142 based on its potency and breadth against the VOCs Alpha, Beta, Gamma, and Delta for preclinical development into a therapeutic. CV38-142 showed efficacy in a Syrian hamster VOC infection model after post-exposure and therapeutic application and revealed a favorable safety profile in a human protein library screen and tissue cross-reactivity study.

The pre-exposure SARS-CoV-2-specific T cell repertoire determines the quality of the immune response to vaccination.

SARS-CoV-2 infection and vaccination generates enormous host-response heterogeneity and an age-dependent loss of immune-response quality. How the pre-exposure T cell repertoire contributes to this heterogeneity is poorly understood. We combined analysis of SARS-CoV-2-specific CD4 T cells pre- and post-vaccination with longitudinal T cell receptor tracking.

The long term vaccine-induced anti-SARS-CoV-2 immune response is impaired in quantity and quality under TNFα blockade.

The humoral immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in patients with chronic inflammatory disease (CID) declines more rapidly with tumor necrosis factor-α (TNF-α) inhibition. Furthermore, the efficacy of current vaccines against Omicron variants of concern (VOC) including BA.2 is limited.

Humoral immune response after different SARS-CoV-2 vaccination regimens.

Background: The humoral immune response after primary immunisation with a SARS-CoV-2 vector vaccine (AstraZeneca AZD1222, ChAdOx1 nCoV-19, Vaxzevria) followed by an mRNA vaccine boost (Pfizer/BioNTech, BNT162b2; Moderna, m-1273) was examined and compared with the antibody response after homologous vaccination schemes (AZD1222/AZD1222 or BNT162b2/BNT162b2).

Methods: Sera from 59 vaccinees were tested for anti-SARS-CoV-2 immunoglobulin G (IgG) and virus-neutralising antibodies (VNA) with three IgG assays based on (parts of) the SARS-CoV-2 spike (S)-protein as antigen, an IgG immunoblot (additionally contains the SARS-CoV-2 nucleoprotein (NP) as an antigen), a surrogate neutralisation test (sVNT), and a Vero-cell-based virus-neutralisation test (cVNT) with the B.1.

Antiviral susceptibility of recombinant Herpes simplex virus 1 strains with specific polymerase amino acid changes.

Acyclovir (ACV) and penciclovir and their prodrugs are recommended for therapy or prophylaxis of Herpes simplex virus 1 (HSV-1) infections. Their administration, however, can lead to the emergence of resistant strains with altered viral thymidine kinase (TK) function, especially in immunocompromised patients. Furthermore, amino acid (aa) changes of the viral deoxyribonucleic acid polymerase (POL) may contribute to resistance to the aforementioned nucleoside analogues.

Development of SARS-CoV-2 Specific IgG and Virus-Neutralizing Antibodies after Infection with Variants of Concern or Vaccination.

The humoral immunity after SARS-CoV-2 infection or vaccination was examined. Convalescent sera after infection with variants of concern (VOCs: B.1.

[COVID-19 in Schleswig-Holstein: infection epidemiological evaluations from March to September 2020].

The COVID-19 pandemic poses major challenges for the German notification system in public infection control. For the federal state of Schleswig-Holstein evaluations, the state reporting office supports the public health departments by providing daily and weekly evaluations and supports the transmission of notification data to the Robert Koch Institute according to the Infection Protection Act.In the present report of the state notification office of Schleswig-Holstein, the SARS-CoV‑2 reporting data for the period from March to September 2020 are evaluated.

Performance of a Point-of-Care Test for the Rapid Detection of SARS-CoV-2 Antigen.

The rapid detection of infections caused by the (SARS-CoV-2) is necessary in the ongoing pandemic. Antigen-specific point-of-care tests (POCT) may be useful for this purpose. Here, such a POCT (SARS-CoV-2 NADAL COVID-19 Ag) was compared to a laboratory-developed triplex real-time polymerase chain reaction (RT-PCR) designed for the detection of viral nucleoprotein gene and two control targets.

Kinetics of Nucleo- and Spike Protein-Specific Immunoglobulin G and of Virus-Neutralizing Antibodies after SARS-CoV-2 Infection.

Kinetics of neutralizing antibodies and immunoglobulin G (IgG) against the nucleo (N) or spike (S) proteins of (SARS-CoV-2) were studied in patients up to 165 days after PCR diagnosis of infection. Two immunoassays were selected out of eight IgG or total antibody tests by comparing their specificities and sensitivities. Sensitivities were calculated with convalescent sera from 26 PCR-confirmed cases, of which 76.

Relevance of non-synonymous thymidine kinase mutations for antiviral resistance of recombinant herpes simplex virus type 2 strains.

Therapy or prophylaxis of herpes simplex virus type 2 (HSV-2) infections with the nucleoside analog aciclovir (ACV) can lead to the emergence of drug-resistant HSV-2 strains, particularly in immunocompromised patients. In this context, multiple amino acid (aa) changes can accumulate in the ACV-converting viral thymidine kinase (TK) which hampers sequence-based diagnostics significantly. In this study, the so far unknown or still doubted relevance of several individual aa changes for drug resistance in HSV-2 was clarified.