Tumour-associated surface antigen(s) in human astrocytomas.

The cytotoxic properties of a hetero-antiserum have been used to demonstrate surface antigen(s) common to seven human astrocytomas. This has been designated human astrocytoma-associated antigen (HAAA). Tissue cultures of astrocytomas were prepared. A rabbit antiserum was raised to one of these and its antibody activity on the original tumour cells assayed by dye exclusion cytotoxicity testing. After repeated absorption with associated antigen(s). In a series of absorption experiments, HAAA was detected in six other human astrocytoma cultures, but not found in a series of other human tumours and tissues tested. Homogenates of two original astrocytomas absorbed out HAAA activity in a similar way indicating the presence of the antigen(s) in vivo. The significance of this HAAA is discussed.