Preparation of antisera with specificity for human T lymphocytes.

Antisera were raised in rabbits and sheep against human or monkey thymocyte or lymphocyte antigens. The unabsorbed antisera reacted equally strongly with T and B lymphoblasts. After partial absorption with B lymphoblasts antisera were specific for T lymphoblasts when tested by cytotoxicity, but still reacted with B lymphoblasts in indirect immunofluorescence. Extensive absorption with reusable columsn made from B cell antigens produced sera which reted selectively with T lymphoblasts and T leukaemic cells and were able to differentiate T and B cells in human peripheral blood.