Evidence that β7 Integrin Regulates Hematopoietic Stem Cell Homing and Engraftment Through Interaction with MAdCAM-1

Stem Cells Dev. 2016 Jan 1;25(1):18-26. doi: 10.1089/scd.2014.0551. Epub 2015 Nov 5.


α4β7 integrin is a cell adhesion receptor that is crucial for the migration of hematopoietic progenitors and mature effector cells in the periphery, but its role in adult hematopoiesis is controversial. We identified a subset of hematopoietic stem cells (HSCs) in the bone marrow (BM) that expressed β7 integrin. These β7(+) HSCs were capable of multilineage, long-term reconstitution and had an inherent competitive advantage over β7(-) HSCs. On the other hand, HSCs that lacked β7 integrin (β7KO) had reduced engraftment potential. Interestingly, quantitative RT-PCR and flow cytometry revealed that β7KO HSCs expressed lower levels of the chemokine receptor CXCR4. Accordingly, β7KO HSCs exhibited impaired migration abilities in vitro and BM homing capabilities in vivo. Lethal irradiation induced expression of the α4β7 integrin ligand-mucosal addressin cell adhesion molecule-1 (MAdCAM-1) on BM endothelial cells. Moreover, blocking MAdCAM-1 reduced the homing of HSCs and impaired the survival of recipient mice. Altogether, these data indicate that β7 integrin, when expressed by HSCs, interacted with its endothelial ligand MAdCAM-1 in the BM microenvironment, thereby promoting HSC homing and engraftment.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Marrow Cells / cytology
  • Cell Adhesion Molecules / metabolism*
  • Cell Movement / genetics*
  • Cells, Cultured
  • Female
  • Graft Survival / genetics*
  • Hematopoietic Stem Cell Transplantation*
  • Hematopoietic Stem Cells / metabolism
  • Hematopoietic Stem Cells / physiology*
  • Integrin beta Chains / genetics*
  • Integrin beta Chains / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mucoproteins
  • Protein Binding
  • Stem Cell Niche / genetics


  • Cell Adhesion Molecules
  • Integrin beta Chains
  • Madcam1 protein, mouse
  • Mucoproteins
  • integrin beta7