MOST GAMMA-DELTA-T-CELLS DEVELOP NORMALLY IN BETA-2-MICROGLOBULIN-DEFICIENT MICE

The specificity of T cells bearing gamma-delta T-cell receptors (gamma-delta+ T cells) is poorly characterized. Earlier studies suggest that like alpha-beta+CD8+ T cells, some gamma-delta+ T cells may recognize antigens associated with class I major histocompatibility complex molecules. Alpha-beta+CD8+ T cells are nearly absent in class I-deficient mice (mutant for beta-2-microglobulin), reflecting a requirement for intrathymic "positive selection" of these cells by class I molecules. Here, we examine whether the development of gamma-delta+ T cells is altered in the beta-2-microglobulin mutant mice. We show that the cellularity, marker expression, repertoire, and functional competence of gamma-delta+ T cells are not detectably deficient in beta-2-microglobulin mutant mice. We conclude that class I expression is unnecessary for the development of most gamma-delta+ T cells.