I have some questions concerning CTL recognition of allograft MHC-I
molecules. CTL killing is normally MHC-I restricted, but allografts
obviously possess non-self MHC. One idea presented in an immunology text
is that a large percentage (20% or so) of TCR on CTL are able to
cross-react sufficiently with non-self MHC to result in killing of the
allograft.
If this is the case, and if this cross-reaction of TCR with non-self MHC-I
is an important mechanism in at least the initiation of graft rejection,
then it would seem that the more similar the MHC are, the more easily the
graft would be rejected. This would imply that careful, but not exact,
MHC matching might be somewhat counterproductive.
Where am I wrong or confused or ignorant?
Thanks in advance for your comments, either posted or emailed.
John
