HLA-DRW6 and treatment of acute rejection with antithymocyte globulin.

The influence of DRw6-antigen on graft survival was studied in a single-center study in 223 recipients of a cadaveric kidney. Although graft survival in 148 DRw6-negative recipients was not significantly different from that in 75 DRw6-positive recipients, the percentage of patients without a rejection episode in the first three months after grafting was significantly less in the DRw6-negative recipients (p = 0.03). In DRw6-positive patients who had received rabbit antithymocyte globulin (RATG) as the first antirejection treatment, graft survival was significantly better than in prednisone-treated DRw6-positive recipients. In the DRw6-negative patients RATG treatment also gave better results, but these differences were not significant. When RATG-treated patients were excluded from the analysis, the difference in graft survival between DRw6-negative and DRw6-positive patients became apparent (p = 0.03). These findings show that the negative influence of the DRw6 antigen present in the recipients is counterbalanced by the beneficial effect of RATG treatment for first rejection episodes.