title: VEGFR-3 and CD133 identify a population of CD34+ lymphatic/vascular endothelial precursor cells.
abstract: Human CD133 (AC133)(+)CD34(+) stem and progenitor cells derived from fetal liver and from bone marrow and blood incorporate a functional population of circulating endothelial precursor cells. Vascular endothelial growth factor receptor 3 (VEGFR-3) regulates cardiovascular development and physiological and pathological lymphangiogenesis and angiogenesis. However, the origin of VEGFR-3(+) endothelial cells (ECs) and the mechanisms by which these cells contribute to postnatal physiological processes are not known, and the possible existence of VEGFR-3(+) lymphatic or vascular EC progenitors has not been studied. Using monoclonal antibodies to the extracellular domain of VEGFR-3, we show that 11% +/- 1% of CD34(+) cells isolated from human fetal liver, 1.9% +/- 0.8% CD34(+) cells from human cord blood, and 0.2% +/- 0.1% of CD34(+) cells from healthy adult blood donors are positive for VEGFR-3. CD34(+)VEGFR-3(+) cells from fetal liver coexpress the stem/precursor cell marker CD133 (AC133). Because mature ECs do not express CD133, coexpression of VEGFR-3 and CD133 on CD34(+) cells identifies a unique population of stem and progenitor cells. Incubation of isolated CD34(+)VEGFR-3(+) cells in EC growth medium resulted in a strong proliferation (40-fold in 2 weeks) of nonadherent VEGFR-3(+) cells. Plating of these cells resulted in the formation of adherent VEGFR-3(+)Ac-LDL(+) (Ac-LDL = acetylated low-density lipoprotein) EC monolayers expressing various vascular and lymphatic endothelial-specific surface markers, including CD34, VE-cadherin, CD51/61, CD105, LYVE-1, and podoplanin. These data demonstrate that human CD34(+)CD133(+) cells expressing VEGFR-3 constitute a phenotypically and functionally distinct population of endothelial stem and precursor cells that may play a role in postnatal lymphangiogenesis and/or angiogenesis.
authors.affiliation: Division of Hematology-Oncology, Weill Medical College of Cornell University, New York, NY 10021, USA. pjs2004@med.cornell.edu
authors.forename: Petri
authors.initials: P
authors.lastname: Salven
authors.forename: Satu
authors.initials: S
authors.lastname: Mustjoki
authors.forename: Riitta
authors.initials: R
authors.lastname: Alitalo
authors.forename: Kari
authors.initials: K
authors.lastname: Alitalo
authors.forename: Shahin
authors.initials: S
authors.lastname: Rafii
mesh_terms: D000071916:AC133 Antigen; D015703:Antigens, CD; D018952:Antigens, CD34 / Q000032:analysis; D001773:Blood Cells / Q000145:classification / Q000166:cytology / Q000276:immunology; D018929:Cell Culture Techniques; D002455:Cell Division; D004729:Endothelium, Lymphatic / Q000166:cytology*; D004730:Endothelium, Vascular / Q000166:cytology*; D005312:Fetal Blood / Q000166:cytology; D005333:Fetus / Q000166:cytology; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D016130:Immunophenotyping; D008099:Liver / Q000166:cytology; D010455:Peptides / Q000032:analysis*; D012333:RNA, Messenger / Q000032:analysis; D013234:Stem Cells / Q000145:classification / Q000166:cytology* / Q000276:immunology; D040321:Vascular Endothelial Growth Factor Receptor-3 / Q000032:analysis* / Q000235:genetics
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D018952:Antigens, CD34; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; D012333:RNA, Messenger; D040321:Vascular Endothelial Growth Factor Receptor-3