Role of anti-IgG autoantibodies in kidney transplantation.

To demonstrate whether anti-IgG autoantibodies of different isotypes and specificities play a role in kidney transplantation, pretransplant sera of recipients (a) with well-functioning grafts (n = 40); (b) with reversible rejection episodes that were treated successfully (n = 63); and (c) with irreversible graft rejection (n = 40) were tested for four different anti-IgG autoantibody activities. A protective effect of IgG-anti-F(ab)2 gamma antibodies on graft survival was observed (p less than 0.01). High pretransplant IgG-anti-Fc gamma activity was found to be associated with a low kidney graft survival rate (p less than 0.02). Pretransplant IgM-anti-F(ab)2 gamma and IgM-anti-Fc gamma activities showed no effect on kidney graft outcome.