Interleukin-7, IL-7, is a cytokine invlolved in B cell and T cell development. It is produced by stromal cells in the thymus and bone marrow, as well as intestinal epithelial cells. IL-7 promotes T cell survival. Lymphopenia and Severe Combined Immunodeficiency are associated with low IL-7.
www.genecards.org/cgi-bin/carddisp.pl?gene=IL7. and ElKassar, N. et al. (2010) An overview of IL-7 biology and its use in immunotherapy. J. Immunotoxicol. 7(1):1-7.