title: A monoclonal antibody recognizing CD43 (leukosialin) initiates apoptosis of human hematopoietic progenitor cells but not stem cells.
abstract: CD43 (the major sialoglycoprotein of leukocytes) is an adhesion molecule broadly expressed on hematopoietic cells. A monoclonal antibody recognizing this molecule induces apoptosis of lineage marker-negative bone marrow hematopoietic progenitor cells (HPCs) that express CD34 at a high density (CD34hiLIN-). However, not all cells within this population undergo apoptosis on stimulation via CD43. Dividing progenitor cells are most highly affected, whereas more primitive quiescent cells survive anti-CD43 monoclonal antibody treatment. These surviving cells (1) are enriched for cobblestone area-forming cells, (2) repopulate fragments for human fetal bone implanted into C.B-17 scid/scid mice, (3) have a potential to differentiate in vivo to myeloid and lymphoid cells, and (4) have a high proliferative potential in long-term stromal cell-free liquid culture. These data indicate that cells with hematopoietic stem cell characteristics are relatively resistant to CD43-mediated apoptosis as compared with HPCs. Thus, CD43 may be specifically involved in the regulation of HPC proliferation.
authors.affiliation: Research Department, SyStemix Inc, Palo Alto, CA 94304, USA.
authors.forename: V
authors.initials: V
authors.lastname: Bazil
authors.forename: J
authors.initials: J
authors.lastname: Brandt
authors.forename: S
authors.initials: S
authors.lastname: Chen
authors.forename: M
authors.initials: M
authors.lastname: Roeding
authors.forename: K
authors.initials: K
authors.lastname: Luens
authors.forename: A
authors.initials: A
authors.lastname: Tsukamoto
authors.forename: R
authors.initials: R
authors.lastname: Hoffman
mesh_terms: D000328:Adult; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D015703:Antigens, CD; D018952:Antigens, CD34 / Q000276:immunology; D017209:Apoptosis; D002478:Cells, Cultured; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D007377:Interleukin-3 / Q000494:pharmacology; D051917:Leukosialin; D051379:Mice; D016513:Mice, SCID; D012795:Sialoglycoproteins / Q000276:immunology*; D019089:Stem Cell Factor / Q000494:pharmacology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018952:Antigens, CD34; D007377:Interleukin-3; D051917:Leukosialin; C465014:SPN protein, human; D012795:Sialoglycoproteins; C497863:Spn protein, mouse; D019089:Stem Cell Factor