Prolongation of rat islet xenograft survival in the liver of IFN-gamma-deficient mice.
The cellular mechanisms involved in islet xenograft rejection remain undetermined. In the present study, the role of interferon-gamma (IFN-gamma) in rat islet xenograft rejection was examined with the use of IFN-gamma-deficient mice as recipients and the results were compared with allografts. There was no significant difference in the survival of intrahepatic islet allografts in IFN-gamma-deficient mice compared with that in wild-type mice. In contrast, a marked prolongation of rat islet xenograft survival was obtained in IFN-gamma-deficient mice without immunosuppression when compared with the survival in wild-type mice. In order to dissect the difference, infiltrating cells in the liver in association with rejection were examined with flow cytometry. An expansion of CD8 T cells was seen in the liver of wild-type mice rejecting xenografts compared with isografts. There was no significant change in other cell populations. In IFN-gamma-deficient mice, the expansion of CD8 T cells was seen in the liver rejecting xenografts; however, the time of development was markedly delayed by the time of rejection. These findings suggest that the acute rejection of rat islet xenografts in mice is IFN-gamma-dependent although the exact mechanisms remain unknown.
Maki
T
T
Department of Surgery I, Fukuoka University School of Medicine, Fukuoka, 814-0180, Japan.
Yasunami
Y
Y
Ikehara
Y
Y
Kodama
S
S
Nakano
M
M
Nakayama
T
T
Taniguchi
M
M
Ikeda
S
S
D000818:Animals; D005434:Flow Cytometry; D006085:Graft Survival; D007371:Interferon-gamma / Q000502:physiology*; D016381:Islets of Langerhans Transplantation; D008099:Liver / Q000166:cytology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D051381:Rats; D011917:Rats, Inbred Lew; D013601:T-Lymphocytes / Q000276:immunology; D014183:Transplantation, Heterologous; D014184:Transplantation, Homologous
D007371:Interferon-gamma