Demonstration of HL‐A Antigens on Human Kidney Cells by Means of the Micro‐Immune Adherence Assay

Abstract. The presence of HL‐A antigens on human kidney cells was investigated by means of the micro‐immune adherence assay (MIAA). The MIAA was performed on kidney cells obtained from fresh kidneys and from kidneys stored at ‐96°C, on kidney cells maintained in culture, and on kidney cells stored in liquid nitrogen after programmed freezing. Performed on fresh kidney cells, the MIAA has a reproducibility of 96–97%. Performed on cells from traditionally frozen kidneys, on cells maintained in culture, and on cells kept in liquid nitrogen after programmed freezing, the assay shows poor reproducibility and non‐specific adherence occurs. This might partly explain the differences observed by other investigators in typing and cross‐matching with lymphocytes on the one hand, and kidney cells on the other; for in these procedures kidney cells, usually from a tissue culture, are typed by means of the MIAA. Modern long‐term kidney preserving techniques make it possible to perform the MIAA on fresh kidney cells for typing and cross‐matching in kidney transplantation.