The leucocyte migration technique as an assay of presensitization to human transplantation antigens.

An assay of cell-mediated immunity, the leucocyte migration technique (LMT), has been compared with the commonly used assay of humoral immunity to transplantation antigens, the microlymphocytotoxicity test. Five recently multiply transfused patients and nineteen haemodialysis patients who had been potentially immunized against transplantation antigens were studied by both tests. All five transfused patients gave positive LMT results while only two gave a positive serological test. Sixteen out of nineteen dialysis patients gave positive LMT results compared with nine with known anti-HL-A antibodies and four showing positive serological direct cross-matches. There was no correlation between cell-mediated and humoral immunity as detected by these methods, although there was a tendency, which was not absolute, for positive direct cross-matches between patients' sera and the panel's lymphocytes, to be associated with positive LMT results. There was a significant correlation (P less than 0-05) between the number of blood transfusions received by the dialysis patients and the detection of cytotoxic antibodies but not with the LMT results. It is felt that some of these positive LMT results are due to reactivity with non-HL-A antigens, and that false negative results also occur. For this reason the technique is not of great value in determining presensitization against HL-A before transplantation.