S. M. Bell, R. Aspinall, S. Thompson and P. L. Stern, Department of Zoology, University of Oxford, South Parks Road, Oxford 0X13PS
H-2 gene products are of central importance in immune recognition, and account for the strong transplantation resistance observed between mouse strains. Murine embryonal carcinomo (EC) cells are the tumourigenic stem cells of teratocarcinomas, and they elicit strong transplantation resistance in some allogeneic mouse strains (1) but do not express H-2 antigens. Since it is generally believed that all T cells recognize major histocompatibility complex (MHC) products, the failure to demonstrate murine cytolytic T cell lysis of EC cells under a variety of conditions is not surprising. This includes the use of lectin-dependent and cell-mediated cytotoxicity (LDCC) (2), a procedure capable of revealing the total cytolytic potential of stimulated murine T cell populations regardless of specificity. In contrast to these findings, the results presented here show that xenogeneic rat...