Induced pluripotent stem cells (iPSCs) are widely considered important for developing novel regenerative therapies. A major challenge to the growth and proliferation of iPSCs is the maintenance of their undifferentiated status in xeno- and feeder-free conditions. Basic fibroblast growth factor (bFGF) is known to contribute to the expansion of stem cells; however, bFGF is notoriously heat-labile and easily denatured. Here, we investigate the effects of a series of synthetic sulfated/sulfonated polymers and saccharides on the growth of iPSCs. We observed that these materials effectively prevented the reduction of bFGF levels in iPSC culture media during storage at 37 °C. Some of the tested materials also suppressed heat-induced decline in medium performance and maintained cell proliferation. Our results suggest that these sulfated materials can be used to improve the expansion culture of undifferentiated iPSCs and show the potential of cost effective, chemically defined materials for improvement of medium performance while culturing iPSCs.
Keywords: basic fibroblast growth factor; heparin; induced pluripotent stem cells; polysaccharides; sulfated materials; synthetic polymers.