Antibody Stimulation of Tumor Cells

Summary Antiserum to normal dog kidney cells was found to stimulate cell division in a transformed dog kidney cell line. The stimulation is obtained with the γ-globulin fraction of the antiserum and the effect is removed by absorption of the antiserum with either the transformed dog kidney cell or with primary dog kidney cells. No adaptation to the antiserum occurred after seven passages in antiserum; the cells were still stimulated by the antiserum as compared to normal serum. Because antibody to normal tissues occurs following injury, it is proposed that this may explain the promotion of tumors by tissue injury.