Major-histocompatibility-complex-restricted male skin graft rejection responses in rats

Normal DA (RT1a) female rats rejected male skin isografts when preimmunized with RT1-compatible DA, or ACI (RT1a) male bone marrow cells (BMC), but failed to reject them when preimmunized with RT1-incompatible PvG/c (RT1c), F344 (RT1lvl), or BN (RT1n) male BMC--as well as when they were untreated. DA female rats rendered neonatally tolerant to RT1-incompatible PvG/c female tissues failed to reject, not only DA, but also PvG/c male skin grafts when preimmunized with PvG/c male BMC. DA female rats tolerant of PvG/c female tissues that had rejected DA male skin grafts following immunization with DA male BMC failed to reject PvG/c male skin grafts. These results indicate that in rats, unlike mice, male skin graft rejection responses are MHC-restricted, at least in the DA strain.