BIOL 1010U Lecture Notes - Lecture 13: Interleukin 2, Clonal Anergy, Interleukin 10
Document Summary
Alone is tolerogenic, leads to anergy or deletion. With signal 1, leads to t cell activation. Mechanisms of t cell tolerance: central tolerance: mediated by negative selection in thymus, peripheral tolerance, ignorance. Autoantigen level is so low that anti-self t cells are not activated. Poor mechanism for tolerance: deleterious t cell is still present in. Function can be extended to inhibit autoimmunity and therefore promote. Providing ag through gut (or lungs) can activate these cells and mediate tolerance tolerance periphery of signal 2 secretes il-10) response: clonal deletion. Negative selection can occur in the periphery as well in absence: t cell anergy, t regulatory cells. In the absence signal 2, t cell can become anergic. Anergic t is unresponsive to signals 1 + 2, but recovered by il-2. Absence of cd4+25+ t cells causes autoimmune disease. These cells act by inhibiting il-2 production. Other cells are also regulatory (e. g. th3 secretes tgf-b.
