Kidney transplantatability across a positive cross-match. Cross-match assays and distribution of B lymphocytes in donor tissues.

Lymphocyte subpopulations were determined in peripheral blood, abdominal lymph-nodes, and spleens from renal allograft donors. Percentages of B lymphocytes were low in peripheral blood (mean +/- S.E., 10-0 +/- 1-0%), variable in lymph-nodes (28-8 +/- 3-8), and high in spleens (41-4 +/- 2-1). Microlym-phocytotoxicity cross-match assays in which sera with B-cell-specific antibody were used were invariably negative with peripheral-blood lymphocytes but positive with lymph-node or spleen preparations. Four renal allografts were transplanted when the standard cross-match was positive with spleen or lymph-node but negative with blood. No hyperacute or accelerated rejection was observed. Potential recipients are often denied allografts because of a positive cross-match with either lymph-node or splenic preparations, and this could be avoided in some cases if cross-matches were performed on peripheral blood or B-lymphocyte-depleted splenic or lymph-node preparations. These results accord with those of other workers who found that B-cell pre-sensitisation is not a contraindication to transplantation.