T cells tagged posts

A new study reveals that thymus atrophy may stem from a decline in its ability to protect against DNA damage from free radicals. The damage accelerates metabolic dysfunction in the organ, progressively reducing its production of pathogen-fighting T cells. Common antioxidants may slow thymus atrophy and be a Rx strategy for protecting elderly from infections.

“The thymus ages more rapidly than any other tissue in the body, diminishing the ability of older individuals to respond to new immunologic challenges, including evolving pathogens and the vaccines that may otherwise offer protection from them,” says Howard Petrie of SRI. Starting around puberty, the thymus rapidly decreases in size and loses capacity to produce enough new T cells...

The immune system produces antibodies finely tuned to antigens. Recent research describes how the interaction between T cells (green) and B cells (blue) allows this to take place. Bystander B cells and antigen appear in red.
Credit: Laboratory of Molecular Immunology at The Rockefeller University

Cell Division speeds up as part of antibody selection. Mechanisms that favor selection of B cells capable of producing antibodies with highest affinity for that invader. “2 of the mechanisms that allow high affinity B cells to overwhelm the others,” says Alex Gitlin.

During an infection, B + other immune cells form germinal centers in spleen and lymph nodes, where B cells evolve in a Darwinian-like fashion...