Abstract: | A non species specific lymphocyte differentiation antigen is described which can be detected on plaque forming cells and a small fraction of thymocytes of mice and rats. The antigen is absent from a BALB/c plasma cell tumor and is not detectable on Dexamethasone-resistant thymocytes. On the basis of its occurrence the term TPCA (thymus plasma cell antigen) is proposed for the antigen. A monospecific anti TPCA serum could be prepared which enables the detection of the antigen on about 10% of rat thymocytes. |