Morphological reaction in transplanted small intestines using immunogenetically defined rat strain combinations.

From the inbred rat stains F344, LEW and Brown-Norway (BN), the following combinations were formed: syngeneic (LEW--LEW), weakly allogeneic (F344--LEW) and strongly allogeneic (BN--LEW). A small intestine segment was transplanted using the by-pass technique; after 10 days the graft was removed and histologically investigated. The strongest rejection was found in the lymphatic tissue and the epithelium of the small intestinal transplant. The immunogenetical difference is significant for the survival of the graft: the greater the immunogenetical difference between donor and host, the more severe the morphologically demonstrable rejection reaction.