Do well-to-do and repeatedly rejecting renal allografts express the transplantation antigens similarly on their surface?

We have performed fine-needle aspiration biopsies to well-to-do and repeatedly rejecting renal allografts. After biopsy the aspirated cells were treated either (a) with monospecific rabbit antisera to HLA-ABC, -DR or beta 2m, or (b) with ordinary anti-HLA-A and B alloantisera. After wash, the cell-bound antibody was chased with Staphylococcus aureus Cowan I bacteria and the antibody-binding cell type(s) was analyzed from stained cytocentrifuged cell smears. In normal, non-transplanted human kidneys the passenger leukocytes and (part of) the endothelial cells bound strongly both anti-HLA-ABC and -DR, the tubular cells weakly anti-ABC but not anti-DR while the glomerular cells did not bind either type of antiserum or bound them only very weakly. In 7 or 8 transplants with an excellent postoperative course we were unable to demonstrate the HLA-ABC and DR antigens on the graft endothelial component. Instead, in 7 of 8 transplants with repeated late rejection episodes, both the HLA-ABC and DR antigens were distinctly expressed on the endothelial cells of the graft.