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Recombinant human/mouse/rat Activin A PLUS ™ protein (Qk005)

Human/mouse/rat Activin A PLUS ™ protein is an optimised biologically active truncation of the mature domain of human Activin A protein.  The EC50 and activity in stem cell culture of activin A PLUS is equivalent to the full mature domain activin A.

High purity 24 kDa dimer comprising truncated mature domain of activin A protein, animal-free (AF) and carrier-protein free (CF).  Recombinant Activin A PLUS is designed to be manufactured at scale for cost-effective, large-scale stem cell culture applications.

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1000µg will be despatched as 2 x 500µg

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  • High purity optimized mature domain of human activin A (Uniprot: P08476) – particularly suitable for bulk and scale-up stem cell culture applications

  • >98%, by SDS-PAGE quantitative densitometry

  • Cross-reactivity: human, mouse (murine), rat

  • 24 kDa (dimer)

  • Expressed in E. coli

  • Animal-free (AOF) and carrier protein-free

  • Manufactured in our Cambridge, UK laboratories

  • Lyophilized from acetonitrile, TFA

  • Resuspend in 10mM HCl at >100 µg/ml (provided with protein and free of charge), prepare single use aliquots, add carrier protein if desired and store frozen at -20°C or -80°C


Human Activin A PLUS Qk005 protein bioactivity lot #010

Activin A PLUS activity is determined using an activin-responsive firefly luciferase reporter in HEK293T cells. in triplicate) with a serial dilution of activin A for 6 hours.  Firefly luciferase activity is measured and normalized to the control Renilla luciferase activity.

EC50 = 0.103 ng/ml (4.24 pM).  EC50 is within the expected range of 6 ± 2 pM.  Data from Qk005 lot #104344.


Human Activin A PLUS Qk005 protein purity SDS-PAGE lot #010

Activin A PLUS migrates as a single band at 24 kDa in non-reducing (NR) and 13 kDa as a single monomeric species upon reduction (R).  No contaminating protein bands are visible.

Purified recombinant protein (7 µg) was resolved using 15% w/v SDS-PAGE in reduced (+β-mercaptothanol, R) and non-reduced conditions (NR) and stained with Coomassie Brilliant Blue R250.  Data from Qk005 lot #010.

Further quality assays

  • Mass spectrometry: single species with expected mass

  • Analytical reversed-phase: single sharp peak

  • Endotoxin: <0.005 EU/μg protein (below level of detection)

  • Recovery from stock vial:  >95%

We are a company founded and run by scientists to provide a service and support innovation in stem cell biology and regenerative medicine.  All our products are exceptionally high purity, with complete characterisation and bioactivity analysis on every lot.

Protein background

Activin A is a member of the TGFβ superfamily of growth factors used in stem cell differentiation and maintenance.  Activin A Plus, an engineered optimized form of Activin A, incorporates an N-terminal truncation to remove a disulfide-linked extension. The resulting protein can be manufactured at extremely consistent high yield with no observed changes in bioactivity compared to the wild-type. This form is particularly suitable for large scale stem cell culture processes.

Activin A is involved in regulation of embryogenesis, development of the reproductive system, wound healing and regulation of immune responses in vivo. The activity of Activin A is regulated by the high-affinity inhibitor, follistatin1, and inhibins.  Activins are disulfide-linked homo- and heterodimers of four inhibin β chains. The best characterized are Activin A and Activin B, homodimers of inhibin βA and inhibin βB respectively. Activins, like all other members in the TGF-β superfamily, are synthesized as larger precursors consisting of an N-terminal signal peptide, a pro-domain of 250–350 residues and a highly conserved mature domain. The pro-domain, which is cleaved off in the mature protein, has important roles in the biosynthesis, stabilization, transportation and signalling of the growth factors2.

Our products are for research use only and not for diagnostic or therapeutic use.  Products are not for resale.

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  1. 2 out of 2 people found this helpful

    Potent and stable Activin A PLUS & FGF2-G3


    We were seeking for a good quality replacement for mammalian cell host human growth factors and glad that we chose Qkine. The Activin A PLUS and FGF2-G3 performed better for H9-hESC self-renewal and primitive germ layer differentiation.

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