The CD34(+)CD38- phenotype identifies a population in the bone marrow that is enriched in the steady state for hematopoietic stem cells (HSCs). Following ex vivo culture of CD34(+) cells, HSC content is difficult to measure since committed CD34(+)CD38+ progenitors down-regulate CD38 surface expression during culture. In this study, we sought to define the phenotype of human HSCs following ex vi...

Magnetic resonance imaging (MRI) provides a noninvasive method for studying the fate of transplanted cells in vivo. We studied whether superparamagnetic nanoparticles (CD34 microbeads), used clinically for specific magnetic sorting, can be used as a magnetic cell label for in vivo cell visualization. Human cells from peripheral blood were selected by CliniMACS CD34 Selection Technology (Milteny...

SUPPLEMENTAL FIGURES Supplemental Figure 1. Ex vivo erythroid differentiation of human CD34 hematopoietic progenitor cells was confirmed by flow-cytometric analysis. Dot plots show the expression of hematopoietic progenitor marker CD34, the thrombospondin receptor (CD36), transferrin receptor (CD71), glycophorin A (GPA) expression during ex vivo erythroid differentiation. Gates were defined usi...

We and others have proposed mammalian cells as gene delivery vehicles with the potential for overcoming physiological barriers to viral vectors. To that end, we previously have shown the potential of CD34+ endothelial progenitors for systemic gene delivery in a primate angiogenesis model. Here we seek to explore the utility of CD34+ cells of human origin as vehicles for toxin genes and, in part...

OBJECTIVE To investigate the role of junctional adhesion molecule A (JAM-A) on adhesion and differentiation of human CD34(+) cells into endothelial progenitor cells. METHODS AND RESULTS Tissue healing and vascular regeneration is a multistep process requiring firm adhesion of circulating progenitor cells to the vascular wall and their further differentiation into endothelial cells. The role o...

Mapping protein expression of endothelial cells (EC) in vivo is fundamental to understanding cellular function and may yield new tissue-selective targets. We have developed a monoclonal antibody, MAb J120, to a protein expressed primarily in rat lung and heart endothelium. The antigen was identified as CD34, a marker of hematopoietic stem cells and global marker of endothelial cells in human an...

(1) Background: There are no high-throughput microtissue platforms for generating bone marrow micro-ossicles. Herein, we describe a method the assembly of arrays microtissues from stromal cells (BMSC) in vitro and their maturation into micro-ossicles vivo. (2) Methods: Discs with 50 microwells were used to assemble 3 × 105 BMSCs each on nylon mesh carrier. Microtissues cultured chondrogenic ind...

Delayed engraftment remains a major hurdle after cord blood (CB) transplantation. It may be due, at least in part, to low fucosylation of cell surface molecules important for homing to the bone marrow microenvironment. Because fucosylation of specific cell surface ligands is required before effective interaction with selectins expressed by the bone marrow microvasculature can occur, a simple 30...