Evidence for in vivo reaction of antibody and complement to surface antigens of human cancer cells.

The immune adherence test was used to determine whether antibody and complement in cancer patients are fixed in vivo to tumor cells. Human erythrocytes adhered in vitro to the surface of human cancer cells obtained from autopsy and biopsy. Adherence was enhanced by further addition of the C2 and C3 components of complement, and was diminished by preliminary treatment with antibody to C3 (that is, to beta1C-globulin). The results suggest that tumor associated membrane antigens form complexes in vivo with antibodies and complement.