Disclosed is the use of one or more reprogrammed cells in the preparation of a medicament for replenishing tissue or cells of a cell lineage in a patient, comprising reprogramming committed cells of a first cell lineage to obtain reprogrammed cells, wherein the patient is suffering from a disease, disorder, or condition characterized by tissue damage selected from the group consisting of bone marrow failure, haematological conditions, aplastic anemia, beta-thalassemia, motor neuron disease, Parkinson&rsquos disease, spinal cord injury, muscular dystrophy, kidney disease, multiple sclerosis, congestive heart failure, hepatitis C virus, human immunodeficiency virus, head trauma, lung disease, depression, non-obstructive azoospermia, andropause, menopause, rejuvenation, sclerodenna ulcers, psoriasis, wrinkles, liver cirrhosis, autoimmune disease, alopecia, retinitis pigmentosa, crystalline dystrophy/blindness, diabetes, and infertility, and wherein the reprogrammed cells are obtained by a method of retrodifferentiation and redifferentiation or transdifferentiation comprising: (i) contacting the committed cells with a retrodifferentiating agent that engages a receptor that mediates capture, recognition or presentation of an antigen at the surface of the committed cells whereby a population of retrodifferentiated cells of the patient are obtained, and (ii) culturing the retrodifferentiated cells in a tissue culture medium comprising a differentiation promoting agent selected from the group consisting of an anticoagulant, a chelating agent, an antibiotic, a vitamin, a mineral, a natural or synthetic hormone, an amino acid, a chemical compound, a nucleoside or an analog thereof, an acid or salt thereof, a drug, and a protein whereby a population of reprogrammed cells of the patient are obtained, and wherein the differentiation promoting agent is independent of the retrodifferentiation agent.
