Cell-Mediated
Cytotoxicity
-CD8 cells may become activate via two mechanisms:
1.Host CD4 cells recognize class II MHC- peptide complex on donor APC=s and secrete cytokines that activate B-cells, CD4, CD8,
and macrophages
which are all involved in the rejection reaction.
2.Host CD8 cells recognize class I MHC-antigen
complex on donor graft
cells and become activated
and are capable of lysing graft tissue cells with the aid of CD4 cells (IL-2 &
IFN-().
