title: Podoplanin requires sialylated O-glycans for stable expression on lymphatic endothelial cells and for interaction with platelets.
abstract: O-glycosylation of podoplanin (PDPN) on lymphatic endothelial cells is critical for the separation of blood and lymphatic systems by interacting with platelet C-type lectin-like receptor 2 during development. However, how O-glycosylation controls endothelial PDPN function and expression remains unclear. In this study, we report that core 1 O-glycan-deficient or desialylated PDPN was highly susceptible to proteolytic degradation by various proteases, including metalloproteinases (MMP)-2/9. We found that the lymph contained activated MMP-2/9 and incubation of the lymph reduced surface levels of PDPN on core 1 O-glycan-deficient endothelial cells, but not on wild-type ECs. The lymph from mice with sepsis induced by cecal ligation and puncture, which contained bacteria-derived sialidase, reduced PDPN levels on wild-type ECs. The MMP inhibitor, GM6001, rescued these reductions. Additionally, GM6001 treatment rescued the reduction of PDPN level on lymphatic endothelial cells in mice lacking endothelial core 1 O-glycan or cecal ligation and puncture-treated mice. Furthermore, core 1 O-glycan-deficient or desialylated PDPN impaired platelet interaction under physiological flow. These data indicate that sialylated O-glycans of PDPN are essential for platelet adhesion and prevent PDPN from proteolytic degradation primarily mediated by MMPs in the lymph.
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK; Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, China;
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK;
authors.forename: Tadayuki
authors.initials: T
authors.lastname: Yago
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK; Jiangsu Institute of Hematology, Collaborative Innovation Center of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Fu
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK;
authors.forename: Brett
authors.initials: B
authors.lastname: Herzog
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK;
authors.forename: J Michael
authors.initials: JM
authors.lastname: McDaniel
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK;
authors.forename: Padmaja
authors.initials: P
authors.lastname: Mehta-D'Souza
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK;
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Cai
authors.affiliation: Jiangsu Institute of Hematology, Collaborative Innovation Center of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Changgeng
authors.initials: C
authors.lastname: Ruan
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK;
authors.forename: Rodger P
authors.initials: RP
authors.lastname: McEver
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK;
authors.forename: Christopher
authors.initials: C
authors.lastname: West
authors.affiliation: Jiangsu Institute of Hematology, Collaborative Innovation Center of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Kesheng
authors.initials: K
authors.lastname: Dai
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK;
authors.forename: Hong
authors.initials: H
authors.lastname: Chen
authors.affiliation: Cardiovascular Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK; Jiangsu Institute of Hematology, Collaborative Innovation Center of Hematology, Key Laboratory of Thrombosis and Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Xia
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000166:cytology / Q000378:metabolism*; D016466:CHO Cells; D002450:Cell Communication / Q000187:drug effects / Q000502:physiology*; D003412:Cricetulus; D004151:Dipeptides / Q000494:pharmacology; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D006031:Glycosylation / Q000187:drug effects; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis / Q000235:genetics; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis / Q000235:genetics; D061965:Matrix Metalloproteinase Inhibitors / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D010973:Platelet Adhesiveness / Q000187:drug effects / Q000502:physiology; D011134:Polysaccharides / Q000096:biosynthesis* / Q000235:genetics; D012794:Sialic Acids / Q000235:genetics / Q000378:metabolism; D000098853:Podoplanin
chemical_list: D004151:Dipeptides; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D061965:Matrix Metalloproteinase Inhibitors; D008562:Membrane Glycoproteins; D011134:Polysaccharides; D012794:Sialic Acids; C490441:Pdpn protein, mouse; D000098853:Podoplanin; C078131:N-(2(R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl)-L-tryptophan methylamide; C522362:Mmp2 protein, mouse; C501830:Mmp9 protein, mouse