The SARS-CoV-2 virus can avoid detection and death by CD8 T cells, which are critical in lowering viral load and clearing the infection by recognising and destroying infected cells.
What’s the latest?
- According to a recent study, the SARS-CoV-2 virus has the ability to modify MHC I expression in host cells.
- MHC I plays an important role in alerting the immune system to virally infected cells.
- The virus has evolved numerous ways to block MHC I expression, which the influenza virus does not have.
What exactly is T Cell Immunity?
- T cells, like B cells, create antibodies and play an important role in the immunological response to viral infection.
- To fight against any type of invader, such as a virus, your immune system requires a type of white blood cell called a B cell, which produces antibodies, and a similar-looking white blood cell called a T cell.
- T cells can play a variety of tasks.
- They can function as “killer cells,” attacking infected cells with viruses or other pathogens, or as “helper cells,” assisting B cells in producing antibodies.
How do they work?
- Along with antibodies, the immune system generates a swarm of T cells that can attack viruses.
- Some of these, known as killer T cells (or CD8+T cells), seek out and destroy virus-infected cells.
- Others, known as helper T cells (or CD4+T cells), are essential for immunological tasks such as encouraging the generation of antibodies and killer T cells.
- T cells do not prevent infection since they only become active after a virus has entered the body. They are, nevertheless, necessary for clearing an infection that has already begun.
- In the case of COVID-19, killer T cells may represent the difference between a minor infection and one that necessitates hospitalisation.
Source: https://www.thehindu.com/sci-tech/science/omicron-variants-evolve-strategies-to-evade-t-cell-immunity/article66740254.ece