Qkine activin A and activin A PLUS have equivalent bioactivity

Activin A (Qk001) is frequently used to maintain pluripotency in induced pluripotent and embryonic stem cell cultures. It is also used in many stem cell differentiation protocols, including endoderm lineage differentiation and further maturation into hepatocyte and pancreatic cells. Human recombinant activin A PLUS protein (Qk005) is an optimized biologically active truncation of the mature domain of human activin A protein designed to be manufactured at scale for cost-effective, large-scale stem cell culture applications.  The EC50 and activity in stem cell culture of activin A PLUS is equivalent to the full mature domain activin A.

• Qkine activin A PLUS (Qk005) was bioactive in a quantitative luciferase assay with an EC50 of 7.3 pM.
• This was comparable to bioactivity of full-length activin A (Qk001), which had an EC50 of 10.2 pM.

Activin A activity was determined using the activin-responsive firefly luciferase reporter assay in transiently transfected HEK293T cells. Cells were treated in triplicate with a serial dilution of Qkine activin A (Qk001, green) or activin A PLUS (Qk005, black) for 6 hours. Firefly luciferase activity was measured and normalized.

Qkine recombinant proteins have the advantage of being highly pure and animal origin-free, giving lot-to-lot consistency in bioactivity for long-term reproducible culture of stem cells and organoids.