Hu Recom GDNF, 500 µg

Manufactured by STEMCELL Technologies, this research-use recombinant protein is the human form of glial cell line-derived neurotrophic factor (GDNF), a neurotrophic factor belonging to the transforming growth factor (TGF)-beta superfamily. The GDNF family of ligands signals by binding to specific GDNF-family receptor-alpha (GFRalpha) co-receptors and activates the RET receptor tyrosine kinase; the protein binds specifically to GFRalpha1 prior to forming a complex with RET. Alternative designations include astrocyte-derived trophic factor (ATF, ATF1, ATF2) and glial cell-derived neurotrophic factor, with UniProt accession P39905.

GDNF promotes the survival and morphological differentiation of midbrain dopaminergic neurons in both in vivo and in vitro studies and increases their high-affinity dopamine uptake, and has demonstrated restorative effects on dopaminergic neurons exposed to degenerative toxins. Together with BrainPhys Neuronal Medium and other supplements, the protein can be used to differentiate human pluripotent stem cell (hPSC)-derived neural progenitor cells into neurons.

The lyophilized product is expressed in E. coli with a reported purity of at least 95%, supplied as a sterile-filtered aqueous solution containing sodium citrate and sodium chloride at pH 4.0 prior to lyophilization. The protein is a homodimer of 15.2 kDa subunits with a predicted total molecular mass of 30.4 kDa and shows cross-reactivity with rat GDNF. Biological activity, determined by a cell proliferation assay using C6 cells, corresponds to a specific activity of at least 3.3 x 10^2 units/mg (EC50 less than or equal to 3 microgram/mL); a representative example yielded an EC50 of 2.17 microgram/mL. Endotoxin level is at most 1 EU/microgram as measured by kinetic Limulus amebocyte lysate (LAL) analysis. The product is not classified as hazardous under the 2012 OSHA Hazard Communication Standard and is stable as supplied for 12 months from date of receipt when stored at -20 degree C to -80 degree C.