Why does immune tolerance fail in autoimmune diseases despite normal development of regulatory cells?

Question: Why does immune tolerance fail in autoimmune diseases despite normal development of regulatory cells?
- Keywords:
  immunity
Asked by them20fen to Sally, Mmboyi, Mike, Michael, Jacinta, Gliday, Elkana, Edna, Arnold on 17 Jul 2025.
- Michael Kimwele answered on 17 Jul 2025:
  
  While regulatory T cells (Tregs) are crucial for maintaining immune tolerance, their failure in autoimmune diseases despite normal development can stem from several factors. These include defects in Treg function beyond mere numbers, the influence of other immune cells and inflammatory signals, and the presence of “danger signals” that can override regulatory mechanisms. Essentially, even with sufficient Tregs, the overall immune environment and specific triggers can lead to a breakdown of tolerance and the initiation of autoimmune responses.

Question: Why does immune tolerance fail in autoimmune diseases despite normal development of regulatory cells?