title: Alpha(4)beta(7)/alpha(4)beta(1) dual integrin antagonists block alpha(4)beta(7)-dependent adhesion under shear flow.
abstract: The alpha(4) integrin, alpha(4)beta(7), plays an important role in recruiting circulating lymphocytes to the gastrointestinal tract, where its ligand mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is preferentially expressed on high endothelial venules (HEVs). Dual antagonists of alpha(4)beta(1) and alpha(4)beta(7), N-(2,6-dichlorobenzoyl)-(L)-4-(2',6'-bis-methoxyphenyl)phenylalanine (TR14035) and N-(N-[(3,5-dichlorobenzene)sulfonyl]-2-(R)-methylpropyl)-(D)-phenylalanine (compound 1), were tested for their ability to block the binding of alpha(4)beta(7)-expressing cells to soluble ligand in suspension and under in vitro and in vivo shear flow. Compound 1 and TR14035 blocked the binding of human alpha(4)beta(7) to an (125)I-MAdCAM-Ig fusion protein with IC(50) values of 2.93 and 0.75 nM, respectively. Both compounds inhibited binding of soluble ligands to alpha(4)beta(1) or alpha(4)beta(7) on cells of human or rodent origin with similar potency. Under shear flow in vitro, TR14035 and compound 1 blocked binding of human alpha(4)beta(7)-expressing RPMI-8866 cells or murine mesenteric lymph node lymphocytes to MAdCAM-Ig with IC(50) values of 0.1 and 1 microM, respectively. Intravital microscopy was used to quantitate alpha(4)-dependent adhesion of fluorescent murine lymphocytes in Peyer's patch HEVs. When cells were prestimulated with 2 mM Mn(2+) to activate alpha(4)beta(7) binding to ligand, anti-alpha(4) monoclonal antibody (mAb) [10 mg/kg (mpk) i.v.] blocked adhesion by 95%, and anti-beta(1) mAb did not block adhesion, demonstrating that this interaction was dependent on alpha(4)beta(7). TR14035 blocked adhesion to HEVs [ED(50) of 0.01-0.1 mpk i.v.], and compound 1 blocked adhesion by 47% at 10 mpk i.v. Thus, alpha(4)beta(7)/alpha(4)beta(1) antagonists blocked alpha(4)beta(7)-dependent adhesion of lymphocytes to HEVs under both in vitro and in vivo shear flow.
authors.affiliation: Pharmacology Division, Merck, PO Box 2000, RY8ON-A26, Rahway, NJ 07065, USA. linda_egger@merck.com
authors.forename: Linda A
authors.initials: LA
authors.lastname: Egger
authors.forename: Usha
authors.initials: U
authors.lastname: Kidambi
authors.forename: Jin
authors.initials: J
authors.lastname: Cao
authors.forename: Gail
authors.initials: G
authors.lastname: Van Riper
authors.forename: Ermengilda
authors.initials: E
authors.lastname: McCauley
authors.forename: Richard A
authors.initials: RA
authors.lastname: Mumford
authors.forename: Suzanne
authors.initials: S
authors.lastname: Amo
authors.forename: Russell
authors.initials: R
authors.lastname: Lingham
authors.forename: Thomas
authors.initials: T
authors.lastname: Lanza
authors.forename: Linus S
authors.initials: LS
authors.lastname: Lin
authors.forename: Stephen E
authors.initials: SE
authors.lastname: De Laszlo
authors.forename: David N
authors.initials: DN
authors.lastname: Young
authors.forename: Ihor E
authors.initials: IE
authors.lastname: Kopka
authors.forename: Sharon
authors.initials: S
authors.lastname: Tong
authors.forename: Bill
authors.initials: B
authors.lastname: Pikounis
authors.forename: Evelyn
authors.initials: E
authors.lastname: Benson
authors.forename: Sarah
authors.initials: S
authors.lastname: Warwood
authors.forename: Robert F
authors.initials: RF
authors.lastname: Bargatze
authors.forename: William K
authors.initials: WK
authors.lastname: Hagmann
authors.forename: John A
authors.initials: JA
authors.lastname: Schmidt
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Detmers
mesh_terms: D000818:Animals; D019138:Antibodies, Blocking / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000276:immunology; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules; D003520:Cyclophosphamide / Q000276:immunology; D004317:Doxorubicin / Q000276:immunology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects; D005047:Etoposide / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007074:Immunoglobulin G / Q000302:isolation & purification / Q000494:pharmacology; D007136:Immunoglobulins; D039041:Integrin alpha4beta1; D016023:Integrins / Q000037:antagonists & inhibitors*; D008024:Ligands; D008214:Lymphocytes / Q000187:drug effects; D008727:Methotrexate / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009088:Mucoproteins / Q000037:antagonists & inhibitors; D010581:Peyer's Patches / Q000166:cytology / Q000187:drug effects; D010649:Phenylalanine / Q000031:analogs & derivatives / Q000494:pharmacology*; D016201:Receptors, Lymphocyte Homing / Q000037:antagonists & inhibitors*; D011993:Recombinant Fusion Proteins / Q000494:pharmacology; D012212:Rheology
chemical_list: D019138:Antibodies, Blocking; D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules; D007074:Immunoglobulin G; D007136:Immunoglobulins; D039041:Integrin alpha4beta1; D016023:Integrins; D008024:Ligands; C504265:MADCAM1 protein, human; C489082:Madcam1 protein, mouse; D009088:Mucoproteins; C459380:N-(2,6-dichlorobenzoyl)-4-(2',6'-bismethoxyphenyl)phenylalanine; C459381:N-(N-((3,5-dichlorobenzene)sulfonyl)-2-methylpropyl)phenylalanine; D016201:Receptors, Lymphocyte Homing; D011993:Recombinant Fusion Proteins; C071777:integrin alpha4beta7; D010649:Phenylalanine; D005047:Etoposide; D004317:Doxorubicin; D003520:Cyclophosphamide; D008727:Methotrexate