A medicament for cell differentiation to alleviate cell and cell-related deficiencies in a mammal is described. The medicament comprises in two or more parts in vitro produced non-activated inducible gene construct(s) capable of expressing transcription factor(s), and optionally additional suppressor(s) or activator(s) of expression of said transcription factor(s), in a cell for transfection, such as a stem cell, and separate exogenous inducer(s) for in vivo expression, such as tetracycline, streptogramin and macrolide. Examples of the cell and cell-related deficiencies are traumatic injuries to the brain and spinal cord, neurodegenerative disorders, stroke, demyelinating disorders, neuropathic pain disorders, diabetes, myocardial infarction, skeletal muscle disorders. Further, a delivery system for delivery of the medicament to a mammal as well as a method of treating cell and cell-related deficiencies in a mammal, are described.
