Chemokine transport across human vascular endothelial cells.
Leukocyte migration across vascular endothelium is mediated by chemokines that are either synthesized by the endothelium or transferred across the endothelium from the tissue. The mechanism of transfer of two chemokines, CXCL10 (interferon gamma-inducible protein [IP]-10) and CCL2 (macrophage chemotactic protein [MCP]-1), was compared across dermal and lung microvessel endothelium and saphenous vein endothelium. The rate of transfer depended on both the type of endothelium and the chemokine. The permeability coefficient (Pe) for CCL2 movement across saphenous vein was twice the value for dermal endothelium and four times that for lung endothelium. In contrast, the Pe value for CXCL10 was lower for saphenous vein endothelium than the other endothelia. The differences in transfer rate between endothelia was not related to variation in paracellular permeability using a paracellular tracer, inulin, and immunoelectron microscopy showed that CXCL10 was transferred from the basal membrane in a vesicular compartment, before distribution to the apical membrane. Although all three endothelia expressed high levels of the receptor for CXCL10 (CXCR3), the transfer was not readily saturable and did not appear to be receptor dependent. After 30 min, the chemokine started to be reinternalized from the apical membrane in clathrin-coated vesicles. The data suggest a model for chemokine transcytosis, with a separate pathway for clearance of the apical surface.
Mordelet
Elodie
E
Department of Biological Sciences, The Open University, Milton Keynes, UK.
Davies
Heather A
HA
Hillyer
Philippa
P
Romero
Ignacio A
IA
Male
David
D
D001692:Biological Transport; D018929:Cell Culture Techniques; D002463:Cell Membrane Permeability; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism*; D054357:Chemokine CXCL10; D019743:Chemokines, CXC / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism*; D017097:Electric Impedance; D004705:Endocytosis; D042783:Endothelial Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D004730:Endothelium, Vascular / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate; D019084:Fluorescent Antibody Technique, Indirect; D005456:Fluorescent Dyes; D006801:Humans; D007444:Inulin / Q000378:metabolism; D007700:Kinetics; D008168:Lung / Q000098:blood supply / Q000166:cytology; D054390:Receptors, CCR2; D054367:Receptors, CXCR3; D019707:Receptors, Chemokine / Q000032:analysis / Q000276:immunology / Q000378:metabolism; D012867:Skin / Q000098:blood supply / Q000166:cytology
C111835:CCL2 protein, human; C515334:CCR2 protein, human; C114753:CXCL10 protein, human; C515187:CXCR3 protein, human; D018932:Chemokine CCL2; D054357:Chemokine CXCL10; D019743:Chemokines, CXC; D005456:Fluorescent Dyes; D054390:Receptors, CCR2; D054367:Receptors, CXCR3; D019707:Receptors, Chemokine; D007444:Inulin; D016650:Fluorescein-5-isothiocyanate