[Specificity of "combi-effect" after xenogenic discordant heart-lung transplantation].
The purpose of this study was to investigate whether the "Combi-Effect" is specific for the transplanted lung tissue or not.


METHODS
In a Guinea-pig to rat model we compared the heterotopic heart-lung transplantation (HLTx, n = 5) with a second heart transplantation (DHTx, n = 5) and a combined heart-kidney transplantation (HKTx, n = 5). Apart from the heart transplant survival time we determined the concentrations of histamine, CH-50, IgG, IgM, leucocytes and thrombocytes in the blood. At time of rejection all tissues were examined histologically and immunohistologically (ED-11, IgG, IgM, OX-39, W3-13, ED-1, NKR-P1, OX-19).


RESULTS
We could achieve a significant prolongation of the heart transplant survival time by combined HLTx compared to HTx (25' to 12', p < 0.01). DHTx showed no effect (7' 53" to 11' 27"). But after HKTx the cardiac survival was even longer than after HTx and HLTx (62.8' to 12' and 25', p < 0.01). CH-50 showed significant lower concentrations after HLTx (180 U/l) and HKTx (178 U/l) than after HTx (260 U/l). Thrombocytes and leucocytes were lower, concentration of histamine higher than after HTx (p < 0.01). Immunohistologically C3 revealed a lower deposition in the rejected heart transplants after combined HLTx/HKTx than after isolated HTx.


CONCLUSIONS
The "Combi-Effect" is stronger after HKTx than after HLTx. He is not specific for the lung tissue.
D000818:Animals; D015941:Complement Hemolytic Activity Assay; D006084:Graft Rejection / Q000276:immunology*; D006168:Guinea Pigs; D016027:Heart Transplantation / Q000276:immunology; D016041:Heart-Lung Transplantation / Q000276:immunology*; D007108:Immune Tolerance / Q000276:immunology; D016030:Kidney Transplantation / Q000276:immunology; D051381:Rats; D011917:Rats, Inbred Lew; D014183:Transplantation, Heterologous / Q000276:immunology*