This invention is concerned with stem cells derived from umbilical cord blood serum and a method for growing human embryonic stem cells and adult cells comprising sera separated from clotted umbilical cord blood, including growing and differentiating cord blood stem cells into neural precursors, comprising transdifferentiating CD34+, CD45+ and CD133+ stem cells from mononuclear cells derived from umbilical cord blood to neural precursors. The stem cells obtained from the umbilical cord include pluripotent stem and progenitor cell population of mononuclear cells, and separating pluripotent stem and progenitor cell population of mononuclear cells obtained from the umbilical cord blood. A magnetic cell separator is used to separate out cells which contain a CD marker and then expanding the cells in a medium containing retinoic acid as a differentiating agent supplemented with one or more growth factors BDNF, GDNF, NGF and FGF in presence of cord blood serum. The invention is also concerned with the transplantation and repair of nerve damage, strokes, spinal injury, Parkinson's and Alzheimer's, prepared with a media for culturing umbilical cord blood stem cells in umbilical cord serum.