Bone marrow stem cells have the ability to populate the entire central nervous system into fully differentiated parenchymal microglia

Abstract

SPECIFIC AIMBone marrow stem cells are capable of differentiating into multiple cell types, though it is still unclear whether they can migrate across the blood–brain barrier (BBB) in many regions of the central nervous system (CNS) and whether these cells can readily differentiate into functional parenchymal microglia. The first aim of this study was to unequivocally determine whether bone marrow-derived cells can migrate across the BBB and populate the brain parenchyma. We then assessed the differentiation fate of these cells once immigrated into the CNS.PRINCIPAL FINDINGS1. Bone marrow-derived stem cells can readily migrate across the BBBTo assess whether stem cells can migrate from the blood circulation to the brain parenchyma, we transplanted GFP-expressing stem cells into lethally irradiated mice. We found that donor-derived cells were present in many regions throughout the brain, from the olfactory bulb to the end of the medulla. Regions that consistently showed a great number of infiltrating GFP-p...