Isolation and characterization of (gamma, delta) CD4+ T cell clones derived from human fetal liver cells.

Lymphocytes isolated from human fetal liver and expanded in vitro in IL- 2-containing media reveal the existence of CD4+ gamma, delta T cells. These cells display differential features of double-negative and CD8+ gamma, delta T cells as well as of CD4+ alpha, beta T cells. Thus, they failed to lyse targets in lectin-mediated killing assays and to perform classical helper functions. These results add new information necessary for a better understanding of the physiological role of the gamma, delta T cells.