Specific anti-T lymphocyte serum.

Continuing our research on specific thymocyte antigens, it was shown that one of these antigens is particularly abundant in the cerebellum and a method has been developed lor its isolation. The activity in immune sera against this antigen, obtained with rat cerebellum, was completely absorbed by analogous human or animal preparations. We therefore used the purified antigen from calf cerebellum to immunize rabbits. The advantage of this method is that it does not require absorption of the immune sera since this purified preparation does not contain undesired antigens common to other cells. Labelled antibodies from these sera allowed detection of human or animal T lymphocytes. However, not all injected animals produced satisfactory immune sera. The problem of the immunochemical structure of the antigen is discussed.