Enhanced apoptosis of peripheral blood mononuclear cells in cardiac transplanted patients undergoing chronic immunosuppressive treatment

Apoptosis plays a major role in tissue transplantation because intact T-cell-apoptosis pathways are required for the induction of tolerance to allografts. Moreover, immunosuppressive agents commonly used in clinical transplantation medicine promote lymphocyte apoptosis inhibiting the expression and production of cytokines involved in lymphocyte survival. The aim of our study was to evaluate peripheral blood mononuclear cells (PBMC) spontaneous apoptosis in patients undergoing chronic immunosuppressive treatment after cardiac transplantation. PBMC obtained from patients (n=31) and controls matched for age and sex (n=25) were cultured for 72 h and apoptosis was evaluated by quantification of fragmented DNA, staining with Hoechst 33258 dye and annexin V binding. We also investigated Fas expression and FasL mRNA expression as well as the ability of an IgM anti-Fas antibody to induce apoptosis. Finally, we evaluated IL2 production induced by PHA and the ability of IL2 to prevent apoptosis. In patients, PBMC underwent enhanced spontaneous apoptosis in comparison with controls. However, we could not find any difference between patients and normals as regards the expression of Fas and of FasL mRNA, even if the cross-linking of the Fas molecule induced apoptosis in PBMC from patients, whereas it failed to induce cell death in normals. We also found that IL2 production was significantly decreased in patients and that the addition of IL2 to the culture medium reduced PBMC spontaneous apoptosis. Our findings suggest that in cardiac transplanted patients PBMC undergo enhanced spontaneous apoptosis, which may contribute to prevent allograft rejection

Abdominal aortic aneurysms in heart transplanted patients.

Objective. In the AA's opinion, the dilatation of the abdominal aorta is not a contraindication to heart transplantation. Methods and Materials. From July 1994 to February 1998, 3 out of 80 heart transplanted patients, required a replacement of their abdominal aorta because of an infrarenal aortic aneurysm. The first patient (62 years old) did not have an aneurysm by time of heart transplantation: his aneurysm (5.1 cm wide) was resected 2 years later. The other two patients (m, 44 years old; m, 60 years old) had a dilatation of 3.1 and 3.5 cm of the abdominal aorta by time of cardiac transplantation: 15 months later, the aneurysms measured 5.8 and 7 cm, respectively, and had been resected. Two resections were performed through a retroperitoneal approach. Results. All 3 patients had uneventful postoperative course. Conclusion. Before heart transplantation the aorta must be screened for dilatation or aneurysm, which can be enlarged by operation. Such lesions can be operated on, with low risks, and should not be a contraindication to heart transplantation

Photopheresis for recurrent acute rejection in cardiac transplantation

[No abstract available