In COVID-19 infection, T-cell immunity is more long-lasting than antibodies. It resides in a subset of white blood cells called T-lymphocytes, or T cells.
Context
- In COVID-19 infection, T-cell immunity is more long-lasting than antibodies. It resides in a subset of white blood cells called T-lymphocytes, or T cells.
What are two types of immunites?
- Innate immunity- It is an immediate response, not strong enough to prevent pathology if the virus is highly virulent or the ‘inoculum’ (infecting virus load) is heavy.
- Adaptive immunity- It takes several days to develop and become effective. It has two arms antibodies and T-cell immunity.
What are T cells?
- A T cellis a type of lymphocyte, which develops in the thymus gland and plays a central role in the immune response.
- T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor on the cell surface.
- T – cells are developed in –i) CD8+ T cells, also known as "killer cells", are cytotoxic and ii) CD4+ T cells which function as "helper cells".
- Unlike CD8+ killer T cells, these CD4+ helper T cells function by indirectly killing cells identified as foreign:
T-cell and testing
- The test known as ‘T- SPOT test’ for assessing T-cell immunity is complicated and expensive.
- T-cell immunity is a better and more durable marker than antibodies of past infection for this novel virus.
