SPECIFIC DESTRUCTION OF HUMAN ENDOTHELIAL CELL MONOLAYERS BY ANTIDRw ANTISERA

Human endothelial cells were separated by collagenase digestion from the umbilical vein of newborns. The cytotoxic effect of antisera against HLA-DRw antigens was tested on monolayers of endothelial cells, using a 51Cr retention microcytotox-icity assay in the presence of rabbit complement. Of the endothelial monolayers tested, significant concordance between the typing results obtained using cord blood-derived B lymphocytes and endothelial cell monolayers was observed. A rabbit anti-human polyspecific B cell antiserum was also capable of completely lysing the endothelial monolayers tested. In addition, 5ICr-labelled dissociated endothelial cells were lysed by nonimmune peripheral blood mononuclear cells in the presence of DRw antisera having a specificity for the target endothelium.