T – CELLS

T – CELLS

Subject : Science & tech

Context :New research: T cells of earlier Covid-19 patients recognise all 3 major new variants.

Concept :

T Cells

• T cells are so called because they are predominantly produced in the thymus.
• They recognise foreign particles (antigen) by a surface expressed, highly variable, T cell receptor (TCR).
• There are two major types of T cells: the helper T cell and the cytotoxic T cell.
• As the names suggest, helper T cells ‘help’ other cells of the immune system, whilst cytotoxic T cells kill virally infected cells and tumours.
• The severity of disease can depend on the strength of these T cell responses.