Different dynamics of soluble inflammatory mediators after clearance of respiratory SARS-CoV-2 versus blood-borne hepatitis C virus infections.

Viral infections can be acute or chronic, with the immune system pivotal in immunopathogenesis. The potential reversibility of inflammation post-viral elimination is of current interest. This study compares the dynamics of soluble inflammatory mediators (SIM) during and after respiratory infections with SARS-CoV-2 and blood-borne acute and chronic hepatitis C virus (HCV) infections.

Molecular Markers Distinguishing T Cell Subtypes With TSDR Strand-Bias Methylation.

Human regulatory CD4CD25FOXP3 T cells (Treg) play important roles in the maintenance of self-tolerance and immune homeostasis in various disease settings and are also involved in the suppression of effective immune responses. These cells are heterogeneous in phenotype and function, and the ability to reliably distinguish between various FOXP3-expressing subpopulations can affect the development of successful therapies. This study demonstrates that hypomethylated CpG sites, present in four regions of the locus, and gene regions, can be used to distinguish several subsets of Treg from conventional CD4 T lymphocytes (Tcon) in donors of both genders.

Regulation of the Germinal Center Response.

The germinal center (GC) is a specialized microstructure that forms in secondary lymphoid tissues, producing long-lived antibody secreting plasma cells and memory B cells, which can provide protection against reinfection. Within the GC, B cells undergo somatic mutation of the genes encoding their B cell receptors which, following successful selection, can lead to the emergence of B cell clones that bind antigen with high affinity. However, this mutation process can also be dangerous, as it can create autoreactive clones that can cause autoimmunity.