Hu/Ms Recom Activin A, 500 µg

Produced by STEMCELL Technologies, this recombinant Activin A protein belongs to the transforming growth factor beta (TGF-β) family and is supplied as a disulfide-linked homodimer of two beta-A chains. The protein signals through SMAD2/3 via heteromeric complexes of type I (Act RI-A, Act RI-B) and type II (Act RII-A, Act RII-B) serine-threonine kinase receptors to regulate cell proliferation, differentiation, wound healing, apoptosis, and metabolism.

The protein is expressed in E. coli, lyophilized from a sterile-filtered solution containing 0.1% trifluoroacetic acid, and has a predicted molecular mass of 26.2 kDa (UniProt accession P08476). Biological activity is determined by the ability to induce cytotoxicity of MPC-11 cells, measured after 48 hours by a fluorometric assay; the EC50 in this assay is 1.9 - 2.9 ng/mL, corresponding to a specific activity of ≥ 1 x 10^5 units/mg. SDS-PAGE under reducing and non-reducing conditions with Coomassie Blue staining confirms ≥ 95% purity, and the endotoxin level is ≤ 1 EU/μg protein by kinetic Limulus amebocyte lysate (LAL) analysis. Cross-reactivity is established for mouse and rat.

Activin A helps maintain the undifferentiated state of human embryonic stem cells and supports their differentiation into definitive endoderm. For use, reconstitute in sterile water to at least 0.1 mg/mL without vortexing; storage at -20°C to -80°C is recommended, where the product remains stable for 12 months from the date of receipt. The product is not classified as a hazardous substance or mixture according to GHS, and is supplied for research use only.