RESUMEN
CCR6 is expressed in a number of dermatological inflammatory diseases. Here, we report that mice sensitized with the hapten oxazolone had increased numbers of CCR6+ T cells in the draining lymph nodes. Using CCR6-/- mice, we assessed the role of CCR6 on the development of contact hypersensitivity. After hapten sensitization and re-challenge, ear swelling in CCR6-/- animals was reduced 80% as compared with wild-type (WT) control mice. This decreased level of inflammation was not related to an inhibition in T-cell activation, because CCR6-/- lymph node cells from sensitized mice produced threefold higher levels of IFN-gamma in culture than cells from sensitized WT mice and, when these cells were directly injected into the site of hapten challenge, induced a robust inflammatory response. However, intravenous injection of CCR6-/- lymph node cells from sensitized mice were unable to prime naive mice to re-challenge whereas cells from primed WT mice were able to sensitize animals. These results suggest that CCR6 plays an important role in directing the trafficking of activated T cells into the skin and suggests that a CCR6 antagonist could be useful to treat skin-mediated inflammatory reactions.
Asunto(s)
Dermatitis por Contacto/inmunología , Dermatitis por Contacto/patología , Receptores CCR6/genética , Receptores CCR6/inmunología , Linfocitos T/patología , Adyuvantes Inmunológicos/toxicidad , Traslado Adoptivo , Animales , Movimiento Celular/inmunología , Expresión Génica/inmunología , Haptenos/farmacología , Interferón gamma/metabolismo , Ganglios Linfáticos/citología , Ganglios Linfáticos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Oxazolona/toxicidadRESUMEN
The synthesis, biological activity, and pharmacokinetic profile of CCR1 antagonists are described.
Asunto(s)
Piperazinas/química , Piperazinas/metabolismo , Receptores de Quimiocina/antagonistas & inhibidores , Animales , Perros , Haplorrinos , Humanos , Microsomas Hepáticos/metabolismo , Piperazinas/síntesis química , Ratas , Receptores CCR1RESUMEN
The present manuscript details structure-activity relationship studies of lead structure 1, which led to the discovery of CCR1 antagonists >100-fold more potent than 1.
Asunto(s)
Receptores de Quimiocina/antagonistas & inhibidores , Línea Celular , Humanos , Receptores CCR1 , Relación Estructura-ActividadRESUMEN
The synthesis, biological activity, and pharmacokinetic profile of novel CCR1 antagonists are described.
Asunto(s)
Receptores de Quimiocina/antagonistas & inhibidores , Animales , Perros , Haplorrinos , Farmacocinética , Receptores CCR1RESUMEN
The chemokines CCL3 and CCL5, as well as their shared receptor CCR1, are believed to play a role in the pathogenesis of several inflammatory diseases including rheumatoid arthritis, multiple sclerosis, and transplant rejection. In this study we describe the pharmacological properties of a novel small molecular weight CCR1 antagonist, CP-481,715 (quinoxaline-2-carboxylic acid [4(R)-carbamoyl-1(S)-(3-fluorobenzyl)-2(S),7-dihydroxy-7-methyloctyl]amide). Radiolabeled binding studies indicate that CP-481,715 binds to human CCR1 with a Kd of 9.2 nm and displaces 125I-labeled CCL3 from CCR1-transfected cells with an IC50 of 74 nm. CP-481,715 lacks intrinsic agonist activity but fully blocks the ability of CCL3 and CCL5 to stimulate receptor signaling (guanosine 5'-O-(thiotriphosphate) incorporation; IC50 = 210 nm), calcium mobilization (IC50 = 71 nm), monocyte chemotaxis (IC50 = 55 nm), and matrix metalloproteinase 9 release (IC50 = 54 nm). CP-481,715 retains activity in human whole blood, inhibiting CCL3-induced CD11b up-regulation and actin polymerization (IC50 = 165 and 57 nm, respectively) on monocytes. Furthermore, it behaves as a competitive and reversible antagonist. CP-481,715 is >100-fold selective for CCR1 as compared with a panel of G-protein-coupled receptors including related chemokine receptors. Evidence for its potential use in human disease is suggested by its ability to inhibit 90% of the monocyte chemotactic activity present in 11/15 rheumatoid arthritis synovial fluid samples. These data illustrate that CP-481,715 is a potent and selective antagonist for CCR1 with therapeutic potential for rheumatoid arthritis and other inflammatory diseases.