ALLOSPECIFIC CYTOTOXIC T-CELLS GENERATED FROM BETA(2)M(- -) MICE IN PRIMARY MLC - ANALYSIS OF ACTIVATION REQUIREMENTS, SPECIFICITY, AND PHENOTYPE/

It has been demonstrated by several investigators that beta(2)m(-/-) k nockout mice are deficient in the expression of MHC Class I molecules but can nevertheless generate CD8(+) allospecific cytotoxic T cells fo llowing vigorous in vivo priming. We demonstrate here that in vivo pri ming is not necessary to generate MHC Class I allospecific CTL from be ta(2)m(-/-) mice. When splenocytes from naive unprimed beta(2)m(-/-) m ice were provided exogenous cytokines in MHC Class I disparate primary MLC, allospecific cytolytic effecters were generated. beta(2)m(-/-) M HC Class I allospecific CTL that were CD3(+) and Thy1.2(+) were otherw ise heterogeneous in phenotype, including CD8(+), CD4(+), CD8(-)CD4(-) , TCR alpha beta(+), and TCR gamma delta(+) T cells. This phenotypic v ariability of beta(2)m(-/-) CTL generated in primary MLC reveals the d iversity of CTL precursors that develop in vivo in the absence of MHC Class I. (C) 1997 Academic Press.