Expression of CD44 isoforms by highly enriched CD34-positive cells in cord blood, bone marrow and leukaphereses.
CD34-positive cells were isolated from cord blood (n = 8), bone marrow (n = 4) and leukapheresed material (n = 7), using an immunomagnetic isolation technique, MACS (Miltenyi Biotec, Bergisch Gladbach, Germany). In flow cytometric analysis, cell populations after enrichment revealed a fraction of 96.1% (cord blood), 96.2% (bone marrow) and 98.6% (leukapheresis material) CD34-positive cells. Cells were further stained with antibodies specific for CD44 isoforms: CD44s (SFF-2), CD44v5 (VFF-8) and CD44v6 (VFF-18). CD44-positive cells were detected by directly (FITC, fluorescein isothiocyanate) or indirectly (streptavidin-PE, phycoerythrin)-conjugated fluorochromes in flow cytometric analysis. Analysis was restricted to CD34-positive cells. A high expression of CD44s was noted in all kinds of material under investigation with mean values in the range of 98.6-100%. There was little expression of CD44v6 (mean values in the range of 1.5-3.6%) and very slight expression of CD44v5 (mean values in the range of 0.6-1.4%). The finding that CD34-positive hematopoietic stem cells express CD44v5 and CD44v6 to a very small extent offers the possibility of using antibodies specific to CD44v5 and CD44v6 in immunopurging in the course of autologous stem cell transplantation.
Neu
S
S
Children's Hospital, University of Tübingen, Germany.
Geiselhart
A
A
Sproll
M
M
Hahn
D
D
Kuçi
S
S
Niethammer
D
D
Handgretinger
R
R
D000328:Adult; D018952:Antigens, CD34 / Q000276:immunology; D001854:Bone Marrow Cells / Q000166:cytology / Q000276:immunology*; D005260:Female; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology*; D005434:Flow Cytometry; D019650:Hematopoietic Stem Cell Mobilization / Q000379:methods; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D018960:Hyaluronan Receptors / Q000096:biosynthesis* / Q000276:immunology; D016130:Immunophenotyping; D007937:Leukapheresis; D011247:Pregnancy
D018952:Antigens, CD34; D018960:Hyaluronan Receptors