Anti-θ Serum-indueed Suppression of the Cellular Transfer of Tumour-specific Immunity to a Syngeneic Plasma Cell Tumour

Abstract

IT has been well documented that tumour-bearing mice can become resistant to their own tumours, especially with chemically induced fibrosarcomas^1–3, and the importance of cell-mediated immune responses rather than humoral antibody in the resistance to tumour transplants has been emphasized^3,4, although the exact mechanism of tumour cell destruction remains ill-defined. Studies in mice^5,6, using allogeneic tumour cells, have demonstrated that thymus-derived (T) lymphocytes are essential for the killing of tumour cells. In addition, using an in vitro method of immunization against histocompatibility antigens, tumour cell destruction either in vitro¹ or in vivo⁸ was shown to be due to T cells alone. In all of these latter studies, however, it is the strong H-2 histocompatibility antigens that are inducing the immune response, and not the tumour-specific transplantation antigens (TSTA). We describe here a specific anti-TSTA response to a murine plasma cell tumour which can be transferred with lymphoid cells, and which can be shown to involve the essential participation of T cells.