背景介绍 IL-21 stimulates proliferation of B-cell stimulated by crosslinking of the CD40 antigen. It inhibits proliferation stimulated by IL-4 plus anti-IgM. IL-21 augments stimulation of the proliferation of naive CD45RA(+) but not memory CD45R0(+) T-cells mediated by engagement of CD3. IL-21 stimulates the proliferation of bone marrow progenitor cells and the expression of the NK-cell marker CD56 in the presence of IL-15. The Interleukin-21 receptor is closely related to human IL-2 beta receptor. The receptor contains a WSXWS motif in the extracellular region, typical of type 1 cytokine receptors. The receptor is expressed on NK-cells, T- cells, and B-cell line. The functional signaling complex activates Janus kinases JAK1, JAK3, and the STAT proteins STAT1, and STAT3. 产品介绍 Recombinant IL-21 is a disulfide-linked homodimeric protein consisting of 132 amino acid residues, and migrates as an approximately 15 kDa protein under non-reducing and reducing conditions in SDS-PAGE. Optimized DNA sequence encoding murine Interleukin-21 mature chain was expressed in E. coli.