Abstract: A synthetic vitreous material contains a self-assembling peptide and a salt, and has an osmotic pressure of 40 mOsm/kg to 200 mOsm/kg. Such a synthetic vitreous material is not toxic to ocular tissue, is capable of maintaining an intraocular tamponade effect over a long term, and is easy to handle and inject into an eye of a patient.

Abstract: Described are methods for isolating/purifying and expanding animal stem cells and stem-cell-like cells. Isolation methods include conditions comprising preferentially digesting non-stem cells and non-stem-cell-like cells in a population and preferentially adhering stem cells and stem-cell-like cells in a population. Expansion methods include culturing such cells under conditions comprising modulation of TGF-? signaling, inhibition of cell signaling mediated by p38 MAP kinase using small molecular weight inhibitors, expansion of the cells on human amniotic epithelial cells as feeder layers, control of cell seeding density, control of levels of Ca2+ in the culture media, rapid adhesion on a substrate or by a combination of such conditions. More particularly, what is disclosed relates to methods and systems for expanding animal cells in ex vivo cell cultures, while preventing cellular differentiation, and selectively enriching stem cells.