title: Endothelial CD99 signals through soluble adenylyl cyclase and PKA to regulate leukocyte transendothelial migration.
abstract: CD99 is a critical regulator of leukocyte transendothelial migration (TEM). How CD99 signals during this process remains unknown. We show that during TEM, endothelial cell (EC) CD99 activates protein kinase A (PKA) via a signaling complex formed with the lysine-rich juxtamembrane cytoplasmic tail of CD99, the A-kinase anchoring protein ezrin, and soluble adenylyl cyclase (sAC). PKA then stimulates membrane trafficking from the lateral border recycling compartment to sites of TEM, facilitating the passage of leukocytes across the endothelium. Pharmacologic or genetic inhibition of EC sAC or PKA, like CD99 blockade, arrests neutrophils and monocytes partway through EC junctions, in vitro and in vivo, without affecting leukocyte adhesion or the expression of relevant cellular adhesion molecules. This is the first description of the CD99 signaling pathway in TEM as well as the first demonstration of a role for sAC in leukocyte TEM.
authors.affiliation: Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60208.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Watson
authors.affiliation: Department of Pharmacology, Weill Medical College of Cornell University, New York, NY 10065.
authors.forename: Jochen
authors.initials: J
authors.lastname: Buck
authors.affiliation: Department of Pharmacology, Weill Medical College of Cornell University, New York, NY 10065.
authors.forename: Lonny R
authors.initials: LR
authors.lastname: Levin
authors.affiliation: Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60208.
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Winger
authors.affiliation: Laboratory of Immunochemistry, WPI Immunology Frontier Research Center and Department of Immunochemistry, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Laboratory of Immunochemistry, WPI Immunology Frontier Research Center and Department of Immunochemistry, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Arase
authors.affiliation: Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60208 wamuller@northwestern.edu.
authors.forename: William A
authors.initials: WA
authors.lastname: Muller
mesh_terms: D000071443:12E7 Antigen; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism*; D015153:Blotting, Western; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D042783:Endothelial Cells / Q000378:metabolism*; D005434:Flow Cytometry; D005822:Genetic Vectors; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D047468:Immunoprecipitation; D007962:Leukocytes / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008863:Microspheres; D034741:RNA, Small Interfering / Q000235:genetics; D015398:Signal Transduction / Q000502:physiology*; D057705:Transendothelial and Transepithelial Migration / Q000502:physiology*
chemical_list: D000071443:12E7 Antigen; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; C522605:Cd99 protein, mouse; D034741:RNA, Small Interfering; D017868:Cyclic AMP-Dependent Protein Kinases; D000262:Adenylyl Cyclases