CD34⁻Hematopoietic Stem Cells: Current Concepts and Controversies

Abstract

ABSTRACT

Identification and Functional Characterization of Ion Channels in CD34+ Hematopoietic Stem Cells from Human Peripheral Blood

“…1C and 1F). CD133 was recently identified as a marker for stem cells and progenitor cells (Guo et al, 2003;Lanza et al, 2001). FACS analysis of CD34 + HSCs revealed that the majority of cells were CD133 + (63.9 ± 8.2 %, Figs.…”

“…CD34, a cell-surface sialomucin commonly used for HSC purification, is suggested to play a role in cellular trafficking and migration (Kronenwett et al, 2000). However, CD34 may not be essential for the physiology of HSCs because normal hematopoietic profiles were found in CD34-null mice (Cheng et al, 1996;Guo et al, 2003). Nielsen et al reported recently that CD34 is abundantly expressed in mature mast cells (Nielsen and MaNagny, 2009).…”

Epigenetic regulations in hematopoietic Hox code

“…In the more differentiated bone marrow cells represented by the CD34 À phenotype, expression levels of the Hox genes are low or absent. In regard to CD34 þ representative of primitive HSCs (Guo et al, 2003), further study demonstrates that Hox genes from clusters A and B are preferentially expressed in the primitive HSC-enriched Sca-1 þ Lin À subpopulation. Their expression is decreased in the HSC-low and depleted subpopulations (Sca-1 þ Lin þ and Sca-1 À Lin þ ) (Pineault et al, 2002).…”

Attributes of adult stem cells

“…Cells are subjected to Hoechst 33 342 dye staining and fluorescence-activated cell sorting (FACS) analysis; those that actively efflux the Hoechst dye appear as a distinct population of cells on the side of the profile, hence the name 'side population' (SP). The SP phenotype of HSCs in mice and humans is largely determined by the expression of a protein known as the ABCG2 transporter (ATP-binding cassette [ABC] subfamily G member 2, also known as BCRP1) [41,42]. A SP is now recognized in many solid organs, a population enriched for clonogenic activity [43].…”