MIMM 214 Lecture Notes - Lecture 20: Mhc Class Ii, Cd154, Mhc Class I
Document Summary
Effector ctls can directly kill infected cells in the periphery. Ctls recognise and kill infected/tumour cells via tcr activation. Signal 1: tcr binds peptide presented by apc on mhc class i. Signal 2: costimulatory signal is transmitted by cd28-b7 interaction between t cell and apc. Signal 3: provided by il-2, inducing proliferation and differentiation into ctl form. Cd8+ specific considerations cd8+ cells require more (stronger) costimulation and il-2 can be autocrine or paracrine from a th1 or th17 cell. One of the critical steps in licensing the apc involves intracellular cd40 signaling. Il-2 produced by cd8+ t cells alone induces proliferation in an autocrine manner. The apc is capable of presenting peptide on mhc i to the cd8+ cell and on mhc ii to the. Note that there is also signaling happening through cd40:cd40l on the cd4+ t cell. Il-2 secreted by both the 4+ and 8+ t cells induce proliferation of the cd8+ t cell (para and autocrine)