Clean-Up Human Embryonic Stem Cell Lines Using Humanized Culture Condition.

Human embryonic stem cell (hESC) culture system has been changing culture conditions from conventional to xeno-free for therapeutic cell applications, and -glycolylneuraminic acid (Neu5Gc) could be a useful indicator of xenogeneic contaminations in hESCs because human cells can no longer produce it genetically. We set up the humanized culture condition using commercially available humanized materials and two different adaptation methods: sequential or direct. SNUhES4 and H1 hESC lines, previously established in conventional culture conditions, were maintained using the humanized culture condition and were examined for the presence of Neu5Gc.

Propagation of Human Embryonic Stem Cells on Human Amniotic Fluid Cells as Feeder Cells in Xeno-Free Culture Conditions.

Human embryonic stem cells (hESCs) have been routinely cultured on mouse embryonic fibroblast feederlayers with a medium containing animal materials. For clinical application of hESCs, animal-derived products from the animal feeder cells, animal substrates such as gelatin or Matrigel and animal serum are strictly to be eliminated in the culture system. In this study, we performed that SNUhES32 and H1 were cultured on human amniotic fluid cells (hAFCs) with KOSR XenoFree and a humanized substrate.

Separation and maintenance of normal cells from human embryonic stem cells with trisomy 12 mosaicism.

Human embryonic stem cells (hESCs) are pluripotent and hold great promise as useful tools in basic scientific research and in the field of regenerative medicine. However, several studies have recently reported chromosomal abnormalities such as gains of chromosomes 12, 17 and X in hESCs. This genetic instability presents an obstacle in the application of hESCs as sources of cell therapies.

Dynamic changes in mitochondrial biogenesis and antioxidant enzymes during the spontaneous differentiation of human embryonic stem cells.

Embryonic cells before implantation are exposed to a hypoxic condition and dependent on anaerobic metabolism. Human embryonic stem cells (HESCs) derived from pre-implantation blastocyst also grow well in hypoxic conditions. Expecting that the differentiating HESCs might mimic anaerobic-to-aerobic metabolic transition of the early human life, we examined the mitochondria-related changes in these cells.

Methods for expansion of human embryonic stem cells.

The manipulation of human embryonic stem cells (hESCs) requires refined skills. Here we introduce both mechanical and enzymatic transfer methods for hESCs depending on experimental purpose. We use the mechanical transfer method for maintenance of hESC lines.

Derivation and characterization of new human embryonic stem cell lines: SNUhES1, SNUhES2, and SNUhES3.

Here we report the derivation and characterization of new human embryonic stem cell (hESC) lines, SNUhES1, SNUhES2, and SNUhES3. These cells, established from the inner cell mass using an STO feeder layer, satisfy the criteria that characterize pluripotent hESCs: The cell lines express high levels of alkaline phosphatase, cell surface markers (such as SSEA-3, SSEA-4, TRA-1-60, and TRA-1-81), transcription factor Oct-4, and telomerase. When grafted into severe combined immunodeficient mice after prolonged proliferation, these cells maintained the developmental potentials to form derivatives of all three embryonic germ layers.