We disclose a method of preparing a conditioned cell culture medium, the method comprising the steps of: (a) culturing a mesenchymal stem cell (MSC), a descendent thereof or a cell line derived therefrom in a cell culture medium; and (b) optionally isolating the cell culture medium; in which the mesenchymal stem cell (MSC) is obtained by propagating a cell obtained by dispersing a embryonic stem (ES) cell colony, or a descendent thereof, in the absence of co-culture in a serum free medium comprising FGF2.