Microcytotoxicity test: detection in sarcoma patients of antibody cytotoxic to human sarcoma cells.

A microcytotoxicity test has been used to detect a factor cytotoxic for human sarcoma cells; the factor was found in serums from 70 percent of sarcoma patients, 58 percent of their family members, and 8 percent of serums from normal blood donors. This cytotoxin is an antibody against a common cell surface sarcoma antigen since it is specific for sarcoma cells, is complement dependent, and is extractable with the globulin fraction of serum.