How is the Development of Autoimmunity Normally Prevented

Question

How is the development of autoimmunity normally prevented?
A) T lymphocytes that respond to autoantigens in the thymus undergo clonal deletion.
B) T lymphocytes require a specific set of cytokine signals to become activated.
C) Regulatory T cells suppress autoimmune responses.
D) Clonal deletion of T cells and regulatory T cell suppression prevent autoreactive T cell activation.
E) Clonal deletion of T cells, lack of necessary cytokine signals, and regulatory T cell suppression prevent activation of autoreactive T cells.

Accepted Answer

The development of autoimmunity is prevented by multiple mechanisms such as clonal deletion of autoreactive T cells in the thymus, lack of necessary cytokine signals, and the suppression of autoimmune responses by regulatory T cells. Choice E includes all these mechanisms and is therefore the best answer.