A method of producing a population of differentiated cells comprising: a) inducing differentiation in a first population of cells by applying an inducer to said cells, b) harvesting microvesicles produced from first population of cells, and c) inducing differentiation in a second population of cells by applying said microvesicles or a derivative thereof to said second population of cells wherein, said first population of cells is autologous to said second population of cells and wherein the inducer applied to said first population of cells is not present in said second population of cells or is only present in trace amounts. Also related methods of producing microvesicles, methods of medical and/or cosmetic treatment and related products and uses.