Cloning, expression and characterization of gene encoding human stem cell growth factor-α and its synergetic effect with rhGM-CSF on proliferation of human umbilical cord mesenchymal stem cells

Abstract:

To investigate the effect of hSCGF-α on human Umbilical Cord Mesenchymal Stem Cells (hUCMSCs), we obtained hSCGF-α using genetic engineering. hSCGF-α gene was amplified from hUCMSCs cDNA using two-step PCR and was inserted into pET-28a(+) plasmid vector. Induced by IPTG at 20 degrees Celsius for 24 h, the fusion protein expressed in E.coli BL21(DE3) was mainly existing in soluble form. The recombinant hSCGF-α was purified using NI-NTA affinity chromatography and the purity was up to 90%. The colony forming test revealed that combined use hSCGF-α and rmGM-CSF (recombinant murine GM-colony stimulating factor, rmGM-CSF) had granulocyte/macrophage (GM) promoting effects on murine bone marrow GM progenitor. In addition, the results indicated that hSCGF-α and rhGM-CSF had stimulatory effect on hUCMSCs and their synergetic effect was the strongest.