Recombinant Human IL-7 (His, Strep)

Interleukin-7 (IL-7) is a 25 kDa hematopoietic family cytokine that plays an important role in lymphocyte differentiation, proliferation, and survival. Human IL-7 cDNA encodes 177 amino acids (aa), including 25 aa signal peptides. Human IL-7 has approximately 60-63% aa sequence identity with mouse, rat, canine, and feline IL-7, and 72-76% with equine, cattle, sheep, pig, cat, and canine IL-7. Human and mouse IL-7 exhibit cross-species activity. IL-7 protein is produced by a variety of cells in primary and secondary lymphoid tissues, including stromal epithelial cells of the thymus, bone marrow, and intestine. Circulating IL-7 protein is limited in healthy animals but increases during lymphopenia. IL-7 signals through a complex of the IL-7 receptor α subunit (IL-7 Rα, also known as CD127) with the common γ chain (γc). IL-7 contributes to the maintenance of all na?ve and memory T cells, primarily by promoting the expression of the anti-apoptotic protein Bcl-2. It is required for optimal T cell-dendritic cell interactions. IL-7 is expressed early in B cell development prior to the appearance of surface IgM. In mice, IL-7 activation of IL-7 Rα is essential for both the development of both T cells and B cell lineages, whereas in humans it is essential for T cells but not for B cell development. However, IL-7 has the function of inhibiting premature Ig light chain recombination during proliferative growth in both mouse and human B protocytes.