Question

Based on what you know about the immune system, EXPLAIN WHY a defect in the gene encoding AIRE would result in a loss of tolerance to self-antigens. What is the function of AIRE? At what stage is it involved in immune development? If AIRE is defective, what are the consequences for the immune system? Be clear and specific!

Answer 1

Answer- Autoimmune regulator (AIRE) is a protein in humans which is encoded by the AIRE gene. AIRE protein is a transcription factor which is expressed in the inner part of thymus.

Function- It is part of the mechanism which eliminates self-reactive T cells. Thus it helps in preventing autoimmune diseases.

Stage of action- In the thymus, the AIRE (being a transcriptional factor) causes transcription of organ-specific genes that create proteins that are usually only expressed in peripheral tissues. It also exposes T cells to normal, healthy proteins from all parts of the body, and T cells that react to those proteins are destroyed.

Effect of defective AIRE- When AIRE is defective, T cells that recognize self antigens can exit the thymus and enter circulation. This can result in a variety of autoimmune diseases.