A two-step, two-signal model for the primary activation of precursor helper T cells

PA Bretscher - Proceedings of the National Academy of …, 1999 - National Acad Sciences
Proceedings of the National Academy of Sciences, 1999National Acad Sciences
I present here a new model for the primary activation of precursor helper T cells.
Observations demonstrate that the immune system learns not to respond to extrathymic,
organ-specific self-antigens because of their early appearance in development. The immune
system thus discriminates between peripheral self-antigens and foreign antigens and, when
mature, usually makes an immune response against only the latter. Contemporary models
for the activation and inactivation of T helper (Th) function do not account for such …
I present here a new model for the primary activation of precursor helper T cells. Observations demonstrate that the immune system learns not to respond to extrathymic, organ-specific self-antigens because of their early appearance in development. The immune system thus discriminates between peripheral self-antigens and foreign antigens and, when mature, usually makes an immune response against only the latter. Contemporary models for the activation and inactivation of T helper (Th) function do not account for such discrimination. The model proposed here is consistent with contemporary findings and incorporates a mechanism of peripheral self–nonself discrimination.
National Acad Sciences