STRONG PROLIFERATIVE RESPONSE, BUT LACK OF CYTOTOXIC EFFECTOR CELL GENERATION TO SYNGENEIC RCS TUMOR IN LYMPHOID CELLS FROM NORMAL AND IMMUNE SJL/J MICE

Abstract

This chapter discusses normal SJL/J lymph node T cells and thymus cells that display a marked proliferative response in vitro to irradiated syngeneic reticulum cell sarcoma (RCS) cells from transplantable tumor lines. The nature of the antigen inducing this response and the possibility that there is cytotoxic cell development in the cultures are examined. The tumor cells lack Thy 1.2 and C 1 receptors, and are insensitive to lysis by anti-Ig and C 1 . However, they have B-cell homing properties, and more than 50% of tumor cells are lysed by antisera to Ia antigens of SJL/J B-cells. The surface antigen inducing 3 H-thymidine incorporation by normal lymph node (LN) cells is resistant to treatment with neuraminidase, pronase, and trypsin. Presence of anti-Ia in the cultures effectively blocks the proliferative response. Treatment of LN cells by anti-Ia + C 1 does not affect their ability to respond, but such treatment of RCS cells abolishes their ability to stimulate. Although irradiated RCS cells could induce specific immunity in SJL/J mice and normal RCS cells show only restricted growth in F l hybrids of SJL/J by C 57 B1 (SBF 1 ) mice, neither cytotoxic serum antibody nor cytotoxic effector cell development are found in SJL/J or SBF 1 mice immunized intraperitoneally with three biweekly injections of irradiated RCS cells. Cytotoxicity is determined on 51 Cr-labeled cells, using 51 cr-labeled PU5 cells (B-cell lymphoma of BALB/c origin) as specificity control cells. RCS cells cause appearance of cytotoxic activity in both peritoneal and spleen cells of allogeneic mice.