Altered distribution of MHC class II antigens on enterocytes during acute small bowel allograft rejection in rats.
Class II major histocompatibility complex (MHC) antigen induction was investigated on enterocytes of heterotopic rat small bowel allografts in the Lewis-Brown Norway strain combination and on isografts in the Lewis-Lewis strain combination. Ia antigens were detected with monoclonal antibodies using an immunoperoxidase technique. Generally, MHC class II antigens were not exhibited in the isografted group, with the exception of two long-term isografts that presented the same pattern as normal small bowel. In these cases, Ia was expressed in a patchy distribution predominantly in the villi, and only very few enterocytes stained positive in Lieberkühn's crypts. Allografted rats showed a typical pattern of Ia expression on the enterocytes during the rejection course. The initial expression was confined to the crypts, indicating a very early stage of rejection when compared to histological findings. More advanced stages of rejection were accompanied by increasing Ia biosynthesis in the crypts and Ia expression by the epithelium lining the villi. Cyclosporin (CyA) was not able to fully inhibit MHC class II antigen expression; however, the appearance of Ia was delayed.
Department of Transplantation Surgery, University Hospital, Innsbruck, Austria.
T
T
Schmid
G
G
Oberhuber
G
G
Körözsi
G
G
Klima
R
R
Margreiter
D000818:Animals; D003524:Cyclosporins / Q000494:pharmacology; D006084:Graft Rejection / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000378:metabolism*; D007150:Immunohistochemistry; D007421:Intestine, Small / Q000187:drug effects / Q000276:immunology / Q000637:transplantation*; D051381:Rats; D011914:Rats, Inbred BN; D011917:Rats, Inbred Lew; D014018:Tissue Distribution; D014184:Transplantation, Homologous; D014185:Transplantation, Isogeneic
D003524:Cyclosporins; D000949:Histocompatibility Antigens Class II