Characterization of B-cell and monocyte antibodies in recipient sera and in eluates from rejected kidney allografts.

The specificity of B-cell antibodies developing in kidney transplant recipients was investigated by blocking with monoclonal anti-DR and chicken anti-human IA antibody. Among 34 recipients who ultimately rejected their kidney allograft, 35% displayed antibodies against B cells before transplantation, most of which were blocked by the anti-DR reagents. Thirty-three of 34 recipients developed B-cell lymphocytotoxins after nephrectomy, and over half of these were not blocked by monoclonal anti-DR. B-cell antibodies were found also in the majority of the kidney eluates, and most of them were shown to be directed against HLA-DR antigens, Monocyte-specific antibodies, which were not blocked by chicken anti-human IA serum, were frequently found in eluates from kidney allografts undergoing rejection. The methods described appear to be useful for the characterization of B-cell and monocyte antibodies developing in kidney transplant recipients. The possibility of correlation with allograft outcome is currently being investigated.