Role of Flk-1 in mouse hematopoietic stem cells.
It was reported that human hematopoietic stem cells in bone marrow were restricted to the CD34(+)KDR(+) cell fraction. We found that expression levels of Flk-1, a mouse homologue of KDR, were low or undetectable in mouse Lin(-)c-Kit(+)Sca-1(+)CD34(low/-) cells as well as Hoechst33342(-) cells (side population), which have long-term reconstitution capacity. Furthermore, neither Flk-1(+)CD34(low/-) cells nor Flk-1(+)CD34(+) cells had long-term reconstitution capacity in mouse. Taken together with other observations using Flk-1-deficient mice, these results indicate that Flk-1 is essential for the development of hematopoietic stem cells in embryo but not for the function of hematopoietic stem cells in adult mouse bone marrow.
Haruta
H
H
Tsukuba Life Science Center, The Institute of Physical and Chemical Research (RIKEN), 3-1 Koyadai, Ibaraki 305-0074, Tsukuba, Japan.
Nagata
Y
Y
Todokoro
K
K
D000818:Animals; D018952:Antigens, CD34 / Q000378:metabolism; D000950:Antigens, Ly / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D029721:Drosophila Proteins; D005260:Female; D006410:Hematopoiesis; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D020297:Mice, Congenic; D008810:Mice, Inbred C57BL; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D017978:Receptors, Growth Factor / Q000378:metabolism*; D040262:Receptors, Vascular Endothelial Growth Factor
D018952:Antigens, CD34; D000950:Antigens, Ly; D002352:Carrier Proteins; D029721:Drosophila Proteins; C074650:Ly6a protein, mouse; D008565:Membrane Proteins; D017978:Receptors, Growth Factor; C410902:lin protein, Drosophila; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases; D040262:Receptors, Vascular Endothelial Growth Factor