Identification and isolation from either adult human bone marrow or G-CSF-mobilized peripheral blood of CD34(+)/CD133(+)/CXCR4(+)/ Lin(-)CD45(-) cells, featuring morphological, molecular, and phenotypic characteristics of very small embryonic-like (VSEL) stem cells.
OBJECTIVE
Recently, we demonstrated that normal human bone marrow (hBM)-derived CD34(+) cells, released into the peripheral blood after granulocyte colony-stimulating factor mobilization, contain cell subpopulations committed along endothelial and cardiac differentiation pathways. These subpopulations could play a key role in the regeneration of post-ischemic myocardial lesion after their direct intracardiac delivery. We hypothesized that these relevant cells might be issued from very small embryonic-like stem cells deposited in the BM during ontogenesis and reside lifelong in the adult BM, and that they could be mobilized into peripheral blood by granulocyte colony-stimulating factor.


METHODS
Samples of normal hBM and leukapheresis products harvested from cancer patients after granulocyte colony-stimulating factor mobilization were analyzed and sorted by multiparameter flow cytometry strategy. Immunofluorescence and reverse transcription quantitative polymerase chain reaction assays were performed to analyze the expression of typical pluripotent stem cells markers.


RESULTS
A population of CD34(+)/CD133(+)/CXCR4(+)/Lin(-) CD45(-) immature cells was first isolated from the hBM or from leukapheresis products. Among this population, very small (2-5 μm) cells expressing Oct-4, Nanog, and stage-specific embryonic antigen-4 at protein and messenger RNA levels were identified.


CONCLUSIONS
Our study supports the hypothesis that very small embryonic-like stem cells constitute a "mobile" pool of primitive/pluripotent stem cells that could be released from the BM into the peripheral blood under the influence of various physiological or pathological stimuli. In order to fully support that hBM- and leukapheresis product-derived very small embryonic-like stem cells are actually pluripotent, we are currently testing their ability to differentiate in vitro into cells from all three germ layers.
Institut de Recherche en Hématologie et Transplantation, Mulhouse, France. hsovalat@yahoo.fr
Hanna
H
Sovalat
Maurice
M
Scrofani
Antoinette
A
Eidenschenk
Stéphanie
S
Pasquet
Valérie
V
Rimelen
Philippe
P
Hénon
D000071916:AC133 Antigen; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D018952:Antigens, CD34 / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology* / Q000378:metabolism; D002454:Cell Differentiation; D002469:Cell Separation; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000378:metabolism; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D019650:Hematopoietic Stem Cell Mobilization; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D016130:Immunophenotyping; D007937:Leukapheresis; D008297:Male; D008875:Middle Aged; D000071317:Nanog Homeobox Protein; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D039904:Pluripotent Stem Cells / Q000166:cytology / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D000071916:AC133 Antigen; D015703:Antigens, CD; D018952:Antigens, CD34; C527276:CXCR4 protein, human; D006023:Glycoproteins; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins; C486780:NANOG protein, human; C095552:NKX2-5 protein, human; D000071317:Nanog Homeobox Protein; D050814:Octamer Transcription Factor-3; C000606023:PROM1 protein, human; D010455:Peptides; D019718:Receptors, CXCR4; D014157:Transcription Factors; D016179:Granulocyte Colony-Stimulating Factor