IL-7 is a hematopoietic growth factor which affects primarily early B and T cells. Produced by thymic stromal cells, spleen cells and keratinocytes, IL-7 can also co-stimulate the proliferation of mature T cells in combination with other factors such as ConA and IL-2. Human and murine IL-7 is cross-species reactive. Recombinant human IL-7 is a 17.4 kDa protein containing 153 amino acid residues. MW: 17.4 kDa. Purity ≥98%