Increased expression of a normal lymphocyte membrane antigen on chronic lymphatic leukemia cells.

Rabbit antisera against a 3 M KCl extract from lymphocytes isolated from tonsils were found to detect an antigen of the normal lymphocyte membrane that on chronic lymphatic leukemia cells is increased in quantity. This increase seems to be specific for chronic lymphatic leukemia. A discrepancy was found between the results obtained with complement-dependent techniques and with methods wherein no complement is used. In complement-dependent methods, the antisera showed a much weaker reaction with normal lymphocytes than would be expected from the amount of antigen present, as established by other methods.