Hu Recom IL-2, ACF, 1000 µg

STEMCELL Technologies supplies an animal component-free preparation of human recombinant Interleukin-2 (IL-2), a monomeric cytokine originally identified as a T cell growth factor. IL-2 binds heterotrimeric receptors composed of CD25, CD122, and CD132, activating JAK3-, STAT5-, and AKT-dependent signaling pathways that drive cellular proliferation and survival. It is primarily secreted by activated CD4+ and CD8+ T cells, with smaller contributions from B cells and dendritic cells, and contributes to the downregulation of immune responses, the development of CD4+CD25+ regulatory T cells, the control of inflammation by inhibiting Th17 differentiation, and the development of follicular helper T cells.

The recombinant protein carries a serine substitution for cysteine at position 126 and is expressed in E. coli with a predicted molecular mass of 15.5 kDa. It is lyophilized from a sterile-filtered aqueous solution containing 0.1% trifluoroacetic acid. According to the product specification, purity is ≥ 97%, the EC50 is ≤ 3 ng/mL as determined by a cell proliferation assay using CTLL-2 cells, the specific activity is approximately 1.8 x 10^4 IU/µg when calibrated against the human recombinant IL-2 WHO International Standard (NIBSC code 86/500), and the endotoxin level is ≤ 0.1 EU/µg protein by kinetic LAL analysis. The product is cross-reactive with mouse, rat, and monkey. It should be stored at -20 to -80°C, is stable as supplied for 12 months from the date of receipt, and is reconstituted in 10 mM hydrochloric acid to at least 0.1 mg/mL.