Forssman-like antibody levels in sera of patients with lung cancer.

Sera of normal individuals or patients with lung cancer were assayed for Forssman-like antibody by a quantitative and specific method using ethylenediaminetetraacetate-containing buffer to inactivate complement in the test serum. It was shown that although Forssman-like antibody levels were distributed widely, (a) the levels of young (20 to 45 years of age) normal subjects of Blood Groups A and AB were lower than those of Blood Groups O and B, (b) the levels of old (60 to 80 years of age) normal subjects were lower than those of young normal subjects of Blood Groups O and B, and (c) the levels of old lung cancer patients were lower when compared to age-matched normal individuals of their blood group.