The ability of stem cell isolation and in vitro culture in the direction defined Hematopoietic progenitor cells then transplanted patients , creates a chance of a new generation of cell therapy in the treatment of a number of defects of the hematopoietic system , including thrombocytopenia. To date, there have been developed in vitro culture procedures which will provide for the purpose of obtaining a sufficient number of precursors megakariopoezy trials . The aim of the work is to develop the ex vivo expansion of megakaryocyte progenitor cells .