Benefits of Repeated SARS-CoV-2 Vaccination and Virus-induced Cross-neutralization Potential in Immunocompromised Transplant Patients and Healthy Individuals.

Background: Current COVID-19 vaccines primarily target the Spike protein of defined virus variants, offering limited protection against emerging variants in immunocompetent individuals. Similarly, protective immunity following natural SARS-CoV-2 infection is variable and of short duration, raising concerns about immunocompromised individuals' vaccination strategies.

Methods: This prospective multicenter study examined 66 sera from 59 immunocompromised and 451 sera from 215 immunocompetent individuals from different pandemic periods.

Rapid cloning-free mutagenesis of new SARS-CoV-2 variants using a novel reverse genetics platform.

Reverse genetic systems enable the engineering of RNA virus genomes and are instrumental in studying RNA virus biology. With the recent outbreak of the coronavirus disease 2019 pandemic, already established methods were challenged by the large genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Herein we present an elaborated strategy for the rapid and straightforward rescue of recombinant plus-stranded RNA viruses with high sequence fidelity using the example of SARS-CoV-2.

Virus Inactivation by Formaldehyde and Common Lysis Buffers.

Numerous mammalian viruses are routinely analyzed in clinical diagnostic laboratories around the globe or serve as indispensable model systems in viral research. Potentially infectious viral entities are handled as blood, biopsies, or cell and tissue culture samples. Countless protocols describe methods for virus fixation and inactivation, yet for many, a formal proof of safety and completeness of inactivation remains to be shown.

Single-cell analysis of human MAIT cell transcriptional, functional and clonal diversity.

Mucosal-associated invariant T (MAIT) cells are innate-like T cells that recognize microbial metabolites through a semi-invariant T cell receptor (TCR). Major questions remain regarding the extent of human MAIT cell functional and clonal diversity. To address these, we analyzed the single-cell transcriptome and TCR repertoire of blood and liver MAIT cells and developed functional RNA-sequencing, a method to integrate function and TCR clonotype at single-cell resolution.

Rapid cloning-free mutagenesis of new SARS-CoV-2 variants using a novel reverse genetics platform.

Reverse genetic systems enable the engineering of RNA virus genomes and are instrumental in studying RNA virus biology. With the recent outbreak of the COVID-19 pandemic, already established methods were challenged by the large genome of SARS-CoV-2. Herein we present an elaborated strategy for the rapid and straightforward rescue of recombinant plus-stranded RNA viruses with high sequence fidelity, using the example of SARS-CoV-2.

MAIT cells in liver inflammation and fibrosis.

Mucosal-associated invariant T cells or MAIT cells are an abundant cell type in humans and especially so in the liver. MAIT cells are a subset of T lymphocytes that sit at a bridge between innate and adaptive immunity, so-called innate-like or "unconventional" T cells. The specificity of their antigen receptor (T cell receptor or TCR) is for the conserved major histocompatibility complex (MHC)-related molecule MR1, which presents a modified bacterial metabolite from the vitamin B2 biosynthesis pathway - this allows them to respond in the presence of many bacteria or yeast.

Stimulatory MAIT cell antigens reach the circulation and are efficiently metabolised and presented by human liver cells.

Objective: Mucosal-associated invariant T (MAIT) cells are the most abundant T cells in human liver. They respond to bacterial metabolites presented by major histocompatibility complex-like molecule MR1. MAIT cells exert regulatory and antimicrobial functions and are implicated in liver fibrogenesis.