title: Hemopoiesis in cellulose ester membrane: characterization of the epilayer responsible for recognition and lodgement of hemopoietic cells.
abstract: Following intraperitoneal (i.p.) insertion of cellulose ester membranes in the mouse, the membranes develop a cellular coat that after sublethal irradiation and i.p. infusion of marrow cells supports the growth of hemopoietic colonies. The uppermost layer of this cellular coat (the epilayer) becomes extremely attenuated and develops numerous microvilli that interact with infused cells to trap and lodge them. This phenomenon is analogous to specific lodging of hemopoietic stem cells in the marrow after bone marrow transplantation. The mechanism of this interaction is not clear, but attention has recently focused on specific interaction of sugar residues of membrane glycoproteins. We have characterized the free surface of this epilayer with various lectins, glycosylated ferritins, and antifactor VIII antibody. There is strong binding of the three lectins Ricinis communis agglutinin (RCA II), phytohemagglutinin (PHA), and wheat germ agglutinin (WGA), but not Ulex europeaus agglutinin, concanavalin A, the tested glycosylated ferritins, or antifactor VIII antibody. The highest density of binding is on microvilli. Since marrow sinus endothelium also strongly binds RCA II, PHA, and WGA, it is possible that the sugar residues of membrane glycoproteins specifically binding these lectins are responsible for cellular and molecular recognition and transport across the epilayer.
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000502:physiology; D002450:Cell Communication; D002462:Cell Membrane / Q000502:physiology / Q000648:ultrastructure; D002482:Cellulose; D004727:Endothelium / Q000502:physiology; D005260:Female; D005347:Fibroblasts / Q000502:physiology / Q000648:ultrastructure; D006023:Glycoproteins / Q000502:physiology; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000502:physiology / Q000648:ultrastructure*; D037102:Lectins; D008264:Macrophages / Q000502:physiology / Q000648:ultrastructure; D008297:Male; D008565:Membrane Proteins / Q000502:physiology; D008567:Membranes, Artificial; D051379:Mice; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D008871:Microvilli / Q000502:physiology; D008954:Models, Biological
chemical_list: D006023:Glycoproteins; D037102:Lectins; D008565:Membrane Proteins; D008567:Membranes, Artificial; D002482:Cellulose