Hematopoietic progenitor cell rolling in bone marrow microvessels: parallel contributions by endothelial selectins and vascular cell adhesion molecule 1.
We have used intravital microscopy to study physiologically perfused microvessels in murine bone marrow (BM). BM sinusoids and venules, but not adjacent bone vessels, supported rolling interactions of hematopoietic progenitor cells. Rolling did not involve L-selectin, but was partially reduced in wild-type mice treated with antibodies to P- or E-selectin and in mice that were deficient in these two selectins. Selectin-independent rolling was mediated by alpha4 integrins, which interacted with endothelial vascular cell adhesion molecule (VCAM)-1. Parallel contribution of the endothelial selectins and VCAM-1 is not known to direct blood cell trafficking to other noninflamed tissues. This combination of constitutively expressed adhesion molecules may thus constitute a BM-specific recruitment pathway for progenitor cells analogous to the vascular addressins that direct selective lymphocyte homing to lymphoid organs.
Mazo
I B
IB
The Center for Blood Research, Harvard Medical School, Boston, Massachusetts 02115, USA.
Gutierrez-Ramos
J C
JC
Frenette
P S
PS
Hynes
R O
RO
Wagner
D D
DD
von Andrian
U H
UH
D000818:Animals; D001853:Bone Marrow / Q000378:metabolism / Q000502:physiology*; D002465:Cell Movement; D019040:E-Selectin / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism / Q000502:physiology; D005260:Female; D005456:Fluorescent Dyes / Q000378:metabolism; D005625:Frontal Lobe / Q000033:anatomy & histology; D006412:Hematopoietic Stem Cells / Q000502:physiology*; D006439:Hemodynamics; D019041:L-Selectin / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008833:Microcirculation; D019007:P-Selectin / Q000378:metabolism*; D020112:Rhodamine 123; D012235:Rhodamines / Q000378:metabolism; D012886:Skull / Q000033:anatomy & histology; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism*; D014699:Venules
D019040:E-Selectin; D005456:Fluorescent Dyes; D019007:P-Selectin; D012235:Rhodamines; D019010:Vascular Cell Adhesion Molecule-1; C026188:rhodamine 6G; D019041:L-Selectin; D020112:Rhodamine 123