The adaptive immune system is endowed with long-lived memory to recall previous antigen
encounters and respond more effectively to them. Memory immune responses are mediated
by antigen-specific memory T lymphocytes that exhibit enhanced function compared with
naïve T cells that have never encountered antigen. While the generation of memory T cells
specific for pathogens is beneficial in providing protective immunity, memory T cells specific
for alloantigens can be deleterious to the recipient of a transplanted organ. In graft rejection …