Interleukin-7 receptor alpha is essential for the development of gamma delta + T cells, but not natural killer cells

Mice that lack a functional gamma c subunit of the receptors for interleukin (IL)-2, IL-4, IL-7, IL-9, and IL-15 display profound defects in lymphoid development. The IL-7/IL-7R system represents a critical interaction for conventional T and B cell development. In this report, the role of IL-7R alpha in the development of lymphoid lineages other than conventional T and B cells was examined. We demonstrate that gamma delta + T cells were absent in IL-7R alpha-deficient mice, whereas the development and function of natural killer cells were normal. Thus, IL-7R alpha function is required for the development of gamma delta + T cells but not natural killer cells.