Amine-enriched surface modification facilitates expansion, attachment, and maintenance of human cardiac-derived c-kit positive progenitor cells

BackgroundStem cells have a low expansion rate and are difficult to maintain in vitro. To overcome the problems of cardiovascular regeneration, we developed a novel method of stem cell cultivation in culture vessels with amine and carboxyl coatings.Methods and resultsWe isolated cardiac stem/progenitor cells from infant-derived heart tissue by using c-kit antibody (human cardiac-derived c-kit positive progenitor cells; hCPCc-kit +); the cells differentiated into endothelial cells, smooth muscle cells, and cardiomyocytes.To characterize the effect of surface modification on hCPCc-kit + expansion, cellular attachment, c-kit expression maintenance, and cardiomyocyte differentiation, we tested hCPCc-kit + cultured on non-coated (control), amine-coated (amine), and carboxyl-coated (carboxyl) vessels.Ex vivo proliferation, c-kit maintenance, and cellular attachment were significantly enhanced in the amine group. The amine coating also increased procollagen type I (pro-COL1) expression and increased phosphorylation signals, such as focal adhesion kinase (FAK) and cytosolic Src, as well as enhanced ERK/CDK2 signaling. In addition, there was significant downregulation of the stress signal transducer, JNK, in the amine group. However, cardiomyogenesis remained unchanged in the control, amine, and carboxyl groups.ConclusionsAlthough surface modifications had no effect on early induction cardiomyogenesis, amine-enriched surface modification may increase hCPCc-kit + expansion. The amine-enriched surface improved cellular proliferation and attachment during ex vivo hCPCc-kit + expansion, possibly by modulating intracellular signal transducers.