Provided is a method of culturing a successor cell from a precursor cell comprising co-culturing a precursor cell such as, without limitation, a human embryonic stem cell or a neuronal stem cell with an adult mesenchymal stem cell. In one embodiment, the adult mesenchymal stem cell is derived from adipose tissue. Also provided is a composition comprising mesenchymal stem cells in a growth matrix biologically-compatible with the cells. In another embodiment, a method of regenerating tissue is provided comprising introducing into a patient a cell growth niche comprising either or both of mesenchymal stem cells and neuronal stem cell or successor cell in a growth matrix biologically-compatible with the cells. In another embodiment, a method of regenerating tissue is provided comprising introducing into a patient a cell growth niche comprising matrix, cells and slow release polymer beads containing growth factors.