Coexpression of two fibronectin receptors, VLA-4 and VLA-5, by immature human erythroblastic precursor cells.

Abstract

Introduction

Differentiation-associated switches in protein 4.1 expression. Synthesis of multiple structural isoforms during normal human erythropoiesis.

“…In contrast, the functional requirements of the plasma membrane of the committed erythroid progenitor are vastly different. These progenitors engage in cell-cell and cell-extracellular matrix adhesion through expression of receptors for matrix components, such as the fibronectin receptors, VLA-4 and VLA-5, and a sialyated macrophage receptor (27)(28)(29)(30)(31)(32). In addition, the progenitor membrane facilitates endocytosis with, for example, transferrin receptor recycling (33-35), while the membrane of mature red cells does not undergo extensive receptor-mediated endocytosis.…”

Mobilization with granulocyte colony-stimulating factor blocks medullar erythropoiesis by depleting F4/80+VCAM1+CD169+ER-HR3+Ly6G+ erythroid island macrophages in the mouse

“…expressed by erythroblasts [45,46]. Furthermore conditional deletion of the Vcam1 or Itga4 gene in mice impairs erythropoietic recovery following cytotoxic or phenylhydrazine challenge [29,30], whereas administration of function-blocking anti-VCAM-1 antibody impairs erythropoietic recovery following BM transplantation [21].…”

Novel secreted isoform of adhesion molecule ICAM-4: potential regulator of membrane-associated ICAM-4 interactions

“…[1][2][3][4][5][6][7][8][9] These molecules mediate erythroblast interactions with both stromal cells and extracellular matrix fibronectin and laminin (reviewed in Hanspal 10 ). Within the bone marrow microenvironment, developing erythroblasts surround a central macrophage forming substructures termed erythroblastic islands (or blood islands).…”