MHC antigens

These are the most important antigens (in humans called HLA) responsible for graft rejection. The surface molecules are divided into class I and class II MHC antigens. Each class of antigens are coded for by genes located at three different loci on chromosome 6; that is, loci A, B and C for class I, and

Donor

Recipient

Autograft (same mouse)

Take

Isograft (similar mouse)

Take

Allograft (different mouse)

Reject

Xenograft (different species)

Figure 11.17. Different types of tissue transplantation (from Benjamini et al., 1996.)

Xenograft (different species)

Reject

Reject loci DR, DQ and DP for class II molecules and numerous different alleles, coding for different molecules, have been described for each locus. Although these antigens have been named and extensively studied in relation to transplantation surgery, they were not designed by nature for that purpose. The physiological role of the MHC antigens is that of antigen presentation in order that lymphocytes can determine whether it is self or non-self.

0 0

Post a comment