Human Activin A is a 26 kDa disulfide-linked homodimer of two beta A chains, each containing 116 amino acid residues. Activin A is a TGF-beta family member with a wide range of biological activities including regulation of cellular proliferation and differentiation, and promotion of neuronal survival. The biological activities of Activin A can be counteracted by inhibins and also by the diffusible TGF-beta antagonist, Follistatin. Animal Free: This product is produced with no animal-derived raw products, animal free equipment and animal free protocols.