Abstract: The method developed herein is for expanding cord blood-derived hematopoietic stem cells to a degree that is sufficiently safe for clinical application, such as the transplantation of hematopoietic stem cells into adult patients. Further, to prepare a number of mesenchymal stem cells or mesenchymal cells that have conventionally been available only in an extremely small number, an immortalizing gene such as that of telomerase is introduced alone into mesenchymal stem cells, mesenchymal cells or the like, so as to induce the differentiation of the expanded mesenchymal stem cells.

Abstract: Mesodermal stem cells or ES cells, prepared from the mononuclear cell fraction isolated from bone marrow fluid or umbilical blood, were found to differentiate into neural stem cells, neurons, or glial cells when cultured in a basal culture medium. In addition, the differentiation of the mesodermal stem cells or ES cells into neural cells was promoted through the addition of an ischemic brain extract to the above-mentioned basal culture medium. Furthermore, the neural cells obtained using the above-described method for inducing differentiation were revealed to have neural regeneration potency in a brain infarction model, a dementia model, a spinal cord injury model and a demyelination model.

Abstract: Demyelinated axons were remyelinated in the demyelinated rat model by collecting bone marrow cells from mouse bone marrow and transplanting the mononuclear cell fraction separated from these bone marrow cells.