Augmentation of in vivo antitumour activity of xenogeneic antiserum by autotransplanted normal spleen cells in mice

Abstract

Inbred CFW/L 1 mice were injected i.p. with 10 5 or 10 6 Ehrlich ascites carcinoma (EAC) cells and 24 hr later were given i.p. injection of rabbit anti-EAC serum. In vivo tumour growth was suppressed with the use of antiserum in 90% of mice injected with 10 5 and in 40% of mice injected with 10 6 EAC cells. Intraperitoneal injection of normal spleen cells into syngeneic or autologous recipients 0.5 hr after inoculation of 10 6 EAC cells augmented the antitumour effect of antiserum and this combined treatment suppressed tumour growth in 90–100% of mice. Syngeneic or autologous spleen cells, when transplanted alone, demonstrated weak but significant antitumour effect in mice inoculated with 10 5 EAC cells. Normal spleen cells from CFW/L 1 donors showed natural as well as significantly higher antibody-dependent cellular cytotoxicity (ADCC) against EAC cells in vitro. In our study we demonstrated the augmentation of in vivo antitumour activity of xenogeneic antiserum by transplantation of normal autologous lymphoid cells.