| abstract |
The invention relates to propagation and differentiation of stem cells and the chemical stimuli which are used in the environment of those cells to induce differentiation. More in particular, the invention provides a method for the ex vivo induction of differentiation of mesenchymal stem cells, preferably derived from adipose tissue, or progenitor cells by adding a polyamine to the cells for a short time (1 min - 2 hours) and subsequent removal. Other differentiation inducing factors may be added in parallel, preferably from the group essentially consisting of steroid hormones, vitamins and/or growth hormones, LMP-I, and combinations of these. The method described preferably provides osteogenic or chondrogenic differentiation, and cells are therefore preferably combined with bioresorbable materials, such as osteoconductive calciumphosphates, bioresorbable polymers such as polylactids or polyglycolids, poly-caprolactones, collagens, minerals, fibrinogens, alginates, hyaluronases, chitosan and/or combinations of these. The stem cells and/or bioresorbable materials will either be directly implanted, or further cultured in the proper culture medium prior to implantation. In addition, polyamine use is described as a method for preventing dedifferentiation of cells and/or inducing transdifferentiation of cells. |