Abstract
The term combi-effect was introduced to describe the phenomenon of a reduction in rejection of heart grafts after combined transplantation with the lung. In this study in rats we investigated whether the combi-effect was an immunological process and whether it could also be induced by combined transplantation of the heart with the spleen or with a lymphocyte-depleted spleen.
Heart and spleen grafts were transplanted into the abdomen; left lungs were transplanted into the thorax of recipient rats. To deplete spleens of their lymphocytes, prospective donor rats were irradiated. Cyclosporine was injected once, on day 2 after transplantation.
All heart allografts transplanted alone and treated with cyclosporine were rejected acutely (median survival time [MST] of 14.5 days). In contrast, after combined transplantation of a donor lung or spleen with the heart, almost all heart grafts survived indefinitely. Transplantation of a syngeneic lung or third-party spleen had little effect on heart graft survival (MST of 22.5 days and 26.5 days, respectively). Without cyclosporine treatment, combined transplantation with a donor lung or spleen hardly prolonged heart graft survival. Transplantation of a lymphocyte-depleted spleen with the heart induced a combi-effect in cyclosporine-treated rats that was somewhat weaker: only two of six hearts survived indefinitely.
We conclude that in the combi-effect an immunological mechanism reduces rejection of the heart. This mechanism is probably generated by the lymphoid tissue (bronchus-associated lymphoid tissue in lung and white pulp in spleen) in the combined transplant.
| Original language | English |
|---|---|
| Pages (from-to) | 952-955 |
| Number of pages | 4 |
| Journal | Transplantation |
| Volume | 52 |
| Issue number | 6 |
| Publication status | Published - Dec-1991 |
Keywords
- SUPPRESSOR CELLS
- LYMPHOID-TISSUE
- MONOCLONAL-ANTIBODIES
- PROLONGED SURVIVAL
- RAT
- CYCLOSPORINE
- ALLOGRAFT
- GRAFTS
- INDUCTION