Coating-Free Culture Medium for Establishing and Maintaining Human Induced Pluripotent Stem Cells.

Cell expansion of human pluripotent stem cells (hPSCs) commonly depends on Matrigel as a coating matrix on two-dimensional (2D) culture plates and 3D microcarriers. However, the xenogenic Matrigel requires sophisticated quality-assurance processes to meet clinical requirements. In this study, we develop an innovative coating-free medium for expanding hPSCs. The xenofree medium supports the weekend-free culture and competitive growth of hPSCs on several cell culture plastics without an additional pre-coating process. The pluripotent stemness of the expanded cells is stably sustained for more than 10 passages, featured with high pluripotent marker expressions, normal karyotyping, and differentiating capacity for three germ layers. The expression levels of some integrins are reduced, compared with those of the hPSCs on Matrigel. This medium also successfully supports the clonal expansion and induced pluripotent stem cell establishment from mitochondrial-defective MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) patient's peripheral blood mononuclear cells. This innovative hPSC medium provides a straightforward scale-up process for producing clinical-orientated hPSCs by excluding the conventional coating procedure.

Mitochondrial Transplantation Moderately Ameliorates Retinal Degeneration in Royal College of Surgeons Rats.

Retinal pigmented epithelial (RPE) cells possess high mitochondria content for energy production, which is required for phagocytosis and vision cycle metabolism. The mitochondrial integrity in RPE cells helps the homeostasis of photoreceptor turnover and prevents retina aging and degeneration. Mitochondrial transplantation benefits the recovery of several acute inflammatory diseases, leading us to investigate the effects of mitochondrial transplantation on retina degeneration. Allogeneic mitochondria were isolated and delivered into the vitreous chamber in the Royal College of Surgeons (RCS) rats, which exhibit inherited and early-onset retina degeneration. The progress of retina degeneration was examined with optical coherence tomography (OCT) and visual evoked potential (VEP) to determine the retina thickness and integrity of afferent electrical signals from affected eyes, respectively. We found that mitochondria engraftment moderately attenuated the degeneration of retinal layers in RCS rats by histological examination. This result was consistent with the OCT measurement of retina thickness around the optic disc. The VEP analysis revealed that the peak one (N1) latency, representing the arriving time of electrical impulse from the retina to cortex, was substantially maintained as the normal value after the mitochondrial transplantation. This result suggests that the intra-vitreous transplanted mitochondria ameliorate the degeneration of photoreceptors in RCS rats and might be potential for clinical application.