In vitro response of peripheral blood mononuclear cells to phytohemagglutinin and interleukin-2

The serological determination of class II antigens is still a mandatory test prior to allotransplantation. It is known that these antigens are normally expressed on B lymphocytes and monocytes. The B lymphocytes that constitute 10% to 15% of total blood lymphocytes are the cells currently used for HLA-DR typing. To avoid HLA-DR typing difficulties, or even impossibilities that are frequently encountered among some patient groups, we studied the response of peripheral blood mononuclear cells--as an alternative source of cells for class II antigen typing--to in vitro mitogen and interleukin-2 activation and propagation. Although the patients included in this study were selected having previously known HLA-DR typing difficulties, all could be adequately typed by this method.