Question

Explain two pieces of evidence that exist that some self-reactive lymphocytes in the immune system of a normal, healthy organism can be missed and maintain the potential to raise an autoimmune reaction? 10points at least 10 lines

Answer 1

Our immune system gaurds against the foreign invaders like bacteria and viruses but in autoimmune diseases our immune system starts attacking self antigens and it releases autoantibodies that attack the normal healthy cells of the body. Example sclerosis, lupus, diabetes type 1, rheumatoid arthritis etc.

Auto immune disorder due to self reactive lymphocyte

1: Alteration of self antigen in rheumatoid arthritis: the cells antigens get altered so that they seem to be foreign to the immune system the new antigenic determinants can attached to to self protein of the body and can lead to change in shape and structure off-the-shelf antigen due to which the t helper cell gets activated and stimulates B lymphocytes to secrete autoantibodies this is is the explanation for production of rheumatoid factor in autoimmune disorder rhematoid arthritis.

2 Hashimoto and Graves disease in female:-These are most common autoimmune disorder of thyroid glands. It involves swelling of the thyroid gland and decrease in production of thyroid hormone such condition is called as hypothyroidism. The self reactive T cells stimulate B lymphocytes to secrete antibody against self antigens like thyroglobulin.

The Graves disease is also called as hyperthyroidism and it involves production of antibodies against thyroid stimulating hormone receptors on the thyroid cells that mimic the action of TSH.

The the B lymphocytes are at greater risk to become autoimmune and autoreactive than compared to T cells , due to alterations in amino acid sequence that changes their specificity towards immune response.