Molecular characterization of embryonic microenvironment that stimulates adult human hematopoietic stem cells to differentiate into neurons

Recent research from the applicant and colleagues has shown that adult human hematopoietic stem cells, derived from bone marrow biopsies, can be stimulated to differentiate into nerve cells by placing them into the injured spinal cord of a chicken embryo. The injured embryonic spinal cord regenerates, and during this regeneration molecular signals clearly are being produced that stimulate the differentiation of the human cells into nerve cells. This shows that stem cells from a patient?s own bone marrow can potentially be used to create nerve cells that could be used to treat brain disease or injury in that patient. This project aims at identifying the molecular signals in the chicken embryo that stimulate this differentiation into nerve cells. Once th ey are identified, the project aims to use them to create a stimulatory environment in a petri dish (in vitro), so that nerve cells can be made from human stem cells directly, without placing them into a chicken embryo. This research is important becau se it may lead to stem cell therapies for brain disease and injury that do not require the use of embryonic stem cells. Bone marrow stem cells are already being used world wide to treat immunological and blood diseases such as leukemia. It is a very wel l characterized and easily handled source of stem cells. Obtaining a standard nethod for producing nerve cells from a patient?s own bone marrow would therefore eliminate many technical and ethical problems associated with using embryonic stem cells or ot her sources of stem cells.