Description_x000D_ General description_x000D_ Recombinant human Interleukin-4 (IL-4) is expressed in human 293 cells as a glycoprotein with a calculated moleculaer mass of 14.9 kDa. This protein is manufactured in human cells using an all-human production system, with full chemically defined ingredients and with no serum. The human cells expression system allows human-like glycosylation and folding, and often supports better stability of the protein in culture._x000D_ Biochem/physiol Actions_x000D_ IL-4 is a protein that has been shown to regulate a wide spectrum of functions in B cells, T cells, monocytes/macrophages and other haematopoietic and non-haematopoietic cells. Among T cell clones, IL-4 is produced by Th0 and Th2 cells, but not Th1 cells, and this has now been demonstrated both in mice and in humans. IL-4 blocks the production of proinflammatory cytokines such IL-6, TNFα, and M-CSF and improves the differentiation of immature DCs from CD34+ progenitors when added during the differentiation period (day 6 to day 12)._x000D_ Interleukin-4 is a lymphokine with profound effects on the growth and differentiation of immunologically competent cells. IL-4 is also known as B cell stimulatory factor-1 (BSF-1), T cell growth factor-2 (TCGF-2) and mast-cell growth factor-2 (MCGF-2). Inhibits VEGF-induced and bFGF-induced angiogenesis. IL-4 is a complex glycoprotein released by a subset of activated T cells. Human and mouse IL-4 share 50% amino acid sequence homology, but their biological actions are species-specific._x000D_ Sequence_x000D_ HKCDITLQEIIKTLNSLTEQKTLCTELTVTDIFAASKNTTEKETFCRAATVLRQFYSHHEKDTRCLGATAQQFHRHKQLIRFLKRLDRNLWGLAGLNSCPVKEANQSTLENFLERLKTIMREKYSKCSS_x000D_ Physical form_x000D_ Supplied as a lyophilized powder containing phosphate buffered saline._x000D_ Analysis Note_x000D_ The biological activity of recombinant human IL-4 was tested in culture by measuring its ability to stimulate proliferation of human TF-1 cells (human erythroleukemic indicator cell line).