1.2000
#29
DETECTION OF PRE AND POSTTRANSPLANT T AND B CELL DONOR SPECIFIC ANTIBODIES BY FLOW CYTOMETRY AND ITS INFLUENCE ON GRAFT OUTCOME.
Jo I.V. Lenaers, Drs, Christina E.M. Voorter, Dr, Maarten H.L. Christiaans, Dr and Ella M. van den Berg-Loonen, Prof Dr. University Hospital Maastricht Tissue Typing Laboratory and Maastricht Netherlands, 6229 HX, Dep of Internal Medicine.

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Donor specific HLA antibodies (DSA) at the time of transplantation are a contraindication for kidney transplantation. The presence of DSA by flow cytometric crossmatches before and after transplantation in correlation with graft outcome was investigated.
In 1997 and 1998 124 transplants were performed. All transplants were performed with a negative current class I CDC-Xm. A positive class II CDC-Xm was accepted unless it was due to specific class II antibodies. For 114 combinations donor lymphocytes were available, follow up was untill 1/9/2003. In the study group 30 grafts failed of which 19 were nephrectomized.
Current T-cell FC-Xm showed 111 patients to be negative and three to have a positive Xm. All three positive T-cell FC-Xm were also B-cell FC-Xm positive and one transplant failed. A further 10 recipients were found to have a positive current B-cell FC-Xm, with 3 showing graft failure.
After transplantation DSA were detected in 38 recipients. 14/38 were FcXm positive for T and B (T+B+), 2 were T+B- and 22 were T-B+. Graft failures were observed in 13/14, 0/2 and 6/22 cases respectively. DSA appeared before graft failure in 8 recipients, of whom 4 were T+B+ and 4 T-B+. From 76 patients with negative FcXm 11 underwent graft failure.
In the study group current sera were positive in 3/114 (3%) T cell and in 10/114 (9%) B cell FcXm. From 114 patients 16 (14%) produced T cell DSA at various times after transplantation, most of them after failure. B cell DSA were also found in 22/114 (19%) of the patients, but with a less deleterious effect on graft outcome.
Presently specific and HLA class of the positive sera are investigated.