Proinflammatory proteases liberate a discrete high-affinity functional FPRL1 (CCR12) ligand from CCL23.

Most chemokines have been found to bind to and signal through single or highly related chemokine receptors. However, a single chemokine protein, a processed form of the alternatively spliced CCL23 (CKbeta8/MPIF-1) gene product, potently engages both the "classical" chemokine receptor CCR1, as well as FPRL1, a type of pattern recognition receptor on innate immune cells. However, the mechanism by which the alternative form of CCL23 is processed is unknown.

CP-481,715, a potent and selective CCR1 antagonist with potential therapeutic implications for inflammatory diseases.

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.

Leukotriene B4 receptor antagonism reduces monocytic foam cells in mice.

Leukotriene B4 (LTB4) is a potent chemotactic agent that activates monocytes through the LTB4 receptor (BLTR). We tested the hypothesis that LTB4 receptor blockade would slow atherosclerotic progression by inhibiting monocyte recruitment. Homozygous low-density receptor knockout (LDLr(-/-)) mice and apolipoprotein E deficient (apoE(-/-)) mice were treated with a specific LTB4 receptor antagonist, CP-105,696, for 35 days.

Antagonizing leukotriene B4 receptors delays cardiac allograft rejection in mice.

Background: Allograft rejection is a cellular immunological/inflammatory response that is, in part, directed by potent proinflammatory mediators. This study was designed to test the hypothesis that leukotriene B4 (LTB4) may have a role in graft rejection and that LTB4 receptor antagonists may be clinically useful in the treatment of allograft rejection.

Methods: We evaluated the potent and selective LTB4 receptor antagonist CP-105696 in a murine heterotopic cardiac allograft model with oral dosing daily for 28 days or in an induction protocol (day -1 to day 3).

trans-3-Benzyl-4-hydroxy-7-chromanylbenzoic acid derivatives as antagonists of the leukotriene B4 (LTB4) receptor.

The SAR of a series of 2-(7-chromanyl)benzoic acids has been investigated with the aim of identifying potent and selective LTB4 receptor antagonists that maintain potency in complex biological fluids. We found optimal activity in derivatives with electron-withdrawing groups in the benzoic acid ring and with an unsubstituted C-3 benzyl group on the chromanol nucleus. While compounds containing a 3-(4-phenyl)benzyl chromanol substituent were potent LTB4 receptor antagonists, the increased lipophilicity imparted by the additional phenyl substituent led to decreased potency in the presence of plasma proteins.

Early eosinophil infiltration into the optic nerve of mice with experimental allergic encephalomyelitis.

Experimental allergic encephalomyelitis is a murine model of preclinical autoimmune disease that has pathologic similarities to multiple sclerosis (MS). Although CD4+ T cells have been shown to play a crucial role in the development of disease, we recently demonstrated a link between the development of paralysis and eosinophil infiltration into the spinal cord. As such, CD4+ cells may initiate disease, but eosinophils may be the actual effector cells responsible for causing damage to myelin and causing paralysis.

The preclinical pharmacological profile of the potent and selective leukotriene B4 antagonist CP-195543.

CP-195543 [(+)-2-(3-benzyl-4-hydroxy-chroman-7-yl)-4-trifluoromethyl-benzoic acid] is a structurally novel, selective and potent leukotriene B4 (LTB4) receptor antagonist. In vitro CP-195543 inhibited [3H]LTB4 binding to high-affinity LTB4 receptors on human neutrophils (HN) and murine spleen membranes with IC50 values of 6.8 nM (Ki = 4.

Pharmacokinetics and pharmacodynamics of the leukotriene B4 receptor antagonist CP-105,696 in man following single oral administration.

Aims: CP-105,696, (+)-1-(3S,4R)-[3-(4-phenylbenzyl)-4-hydroxy-chroman-7-yl] cyclopropane carboxylic acid is a potent, novel LTB4 receptor antagonist advanced to clinical trials to determine its efficacy in inflammatory diseases. The pharmacokinetics and pharmacodynamics of CP-105,696 were investigated in healthy male volunteers following oral administration of single doses of 5 to 640 mg.

Methods: Forty-eight subjects participated in a randomized, double-blind, parallel group study.

The phosphodiesterase type 4 (PDE4) inhibitor CP-80,633 elevates plasma cyclic AMP levels and decreases tumor necrosis factor-alpha (TNFalpha) production in mice: effect of adrenalectomy.

Rolipram was previously reported to elevate plasma cyclic adenosine 3',5'-monophosphate (cAMP) and inhibit serum tumor necrosis factor-alpha (TNF-alpha) production in mice. CP-80,633, a new cyclic nucleotide phosphodiesterase (PDE4) inhibitor, has been shown to augment intracellular cAMP levels and to inhibit TNFalpha release from human monocytes in vitro. This study was undertaken to determine the effect of p.

Biological activity C-X-C and C-C chemokines on leukocyte subpopulations in human whole blood.

We have described an assay that monitors the activating effects of a variety of chemokines on leukocyte subsets in human whole blood. This procedure has the following advantages: (1) minimal manipulation of the cells, (2) maintenance of more physiological conditions, and (3) simultaneous monitoring of the responses of monocytes, neutrophils, and eosinophils.

In vitro pharmacology of the novel phosphodiesterase type 4 inhibitor, CP-80633.

We present the in vitro pharmacology of a novel adenosine 3'-5' -cyclic monophosphate-specific phosphodiesterase (PDE) type 4 inhibitor, CP-80633 ((2'S)5-[3-(2' -exobicyclo[2.2.1]-heptyloxy)4-methoxyphenyl] tetrahydro-2(1H)-primidone), which has shown efficacy in phase II clinical trials for atopic dermatitis.

The in vivo pharmacology of CP-80, 633, a selective inhibitor of phosphodiesterase 4.

The following studies were conducted to characterize the bron-chodilatory and antiinflammatory activity of the novel, selective phosphodiesterase-IV inhibitor, CP-80,633 (2'S)5-[3-(2'-exobicyclo[2.2.1]heptyloxy-4-methoxy-phenyl]te trahydro- 2(1H)-pyrimidone, a compound in clinical development for atopic disease.

Production and characterization of guinea pig IL-5 in baculovirus-infected insect cells.

To study the role interleukin (IL)-5 may play in altering airway function in asthma, we have produced recombinant protein for exogenous administration to guinea pigs. The guinea pig IL-5 (gpIL-5) cDNA was cloned by polymerase chain reaction (PCR) amplification of guinea pig spleen RNA and expressed as a secretion product from recombinant baculovirus-infected Sf9 insect cell cultures. The protein was purified to homogeneity by a four-step procedure that included immunoaffinity chromatography using polyclonal antipeptide antibodies against a region of the mature secreted cytokine.

Inhibition of leukotriene B4-receptor interaction suppresses eosinophil infiltration and disease pathology in a murine model of experimental allergic encephalomyelitis.

Leukotriene B4 (LTB4) is a chemotactic and cell-activating factor present at inflammatory sites in a variety of autoimmune diseases including multiple sclerosis (MS). In this study, we used a murine model of MS, experimental allergic encephalomyelitis (EAE), to assess the potential role of LTB4 on cell infiltration and paralysis. Injection of encephalogenic T cells into naive animals induced paralysis and weight loss that was completely inhibited by treatment with the selective LTB4 receptor antagonist CP-105,696 (ED50= 8.

Characterization of the pharmacological profile of the potent LTB4 antagonist CP-105,696 on murine LTB4 receptors in vitro.

1. Binding of [3H]-leukotriene B4 ([3H]-LTB4) to murine spleen membranes (MSM) was determined. 2.

In vitro and in vivo effects of leukotriene B4 antagonism in a primate model of asthma.

To test the hypothesis that leukotriene (LT) B4 antagonists may be clinically useful in the treatment of asthma, CP-105,696 was evaluated in vitro, using chemotaxis and flow cytometry assays, and in vivo, using a primate asthma model. CP-105,696 inhibited LTB4-mediated monkey neutrophil chemotaxis (isolated cells, LTB4 = 5 nM) and CD11b upregulation (whole blood, LTB4 = 100 nM) with IC50 values of 20 nM and 16.5 microM, respectively.

Expression and biologic characterization of the murine chemokine KC.

KC, the product of an immediate early gene induced in mouse fibroblasts by platelet-derived growth factor, was expressed in Escherichia coli by using a maltose binding protein vector and biochemically characterized as a ligand for both murine and human polymorphonuclear neutrophils (PMN). On murine PMN, KC is both a potent chemoattractant and up-regulator of Mac-1 cell surface expression. On human PMN, in contrast, KC exhibits dissociation of its chemoattractant and Mac-1 up-regulatory activities.

The in vitro and in vivo pharmacologic activity of the potent and selective leukotriene B4 receptor antagonist CP-105696.

CP-105696, (+)-1-(3S,4R)-[3-(4-phenyl-benzyl)-4-hydroxy-chroman-7-yl] cyclopentane carboxylic acid, is a structurally novel, selective and potent leukotriene B4 (LTB4) receptor antagonist. In vitro, CP-105696 inhibited [3H]LTB4 (0.3 nM) binding to high-affinity LTB4 receptors on human neutrophils with an IC50 value of 8.

The Duffy antigen/receptor for chemokines (DARC) is expressed in endothelial cells of Duffy negative individuals who lack the erythrocyte receptor.

The Duffy antigen/receptor for chemokines (DARC), first identified on erythrocytes, functions not only as a promiscuous chemokine receptor but also as a receptor for the malarial parasite, Plasmodium vivax. The recent finding that DARC is ubiquitously expressed by endothelial cells lining postcapillary venules provides a possible insight into the function of this receptor because this anatomic site is an active interface for leukocyte trafficking. However, the biological significance of DARC is questionable since it has not yet been determined whether individuals lacking the expression of this protein on their erythrocytes (Duffy negative individuals), who are apparently immunologically normal, express the receptor on endothelial cells.

Synovial fluid from rheumatoid arthritis patients contains sufficient levels of IL-1 beta and IL-6 to promote production of serum amyloid A by Hep3B cells.

The presence of positive acute phase proteins within the circulation of rheumatoid arthritis patients suggests that elevated cytokine production associated with this chronic inflammatory disorder initiates the hepatic acute phase response. Cytokines produced at inflammatory lesions are believed to travel via the circulation to the liver where they induce acute phase protein production by hepatocytes. To test whether serum from rheumatoid arthritis patients contained sufficient levels of cytokines to promote an acute phase response in vitro, a bioassay was developed that employed the human hepatoma cell line Hep3B.

Prolonged microvascular vasodilation induced by leukotriene B4 in human skin is cyclooxygenase independent.

When the potent chemoattractant leukotriene B4 (LTB4) is applied topically to human skin it causes delayed onset, long-lasting leukocyte accumulation and erythema. We investigated the role of prostaglandins in the increase in local blood flow by applying LTB4 topically to the forearm skin of 22 healthy male volunteers and measuring the effect of the anti-inflammatory compounds tenidap, naproxen and indomethacin. Local microvascular blood flow responses were measured by laser Döppler flow probe and planimetry.

The murine interleukin 8 type B receptor homologue and its ligands. Expression and biological characterization.

KC, the product of an immediate early gene induced in mouse fibroblasts by platelet-derived growth factor, was synthesized as a recombinant protein in Escherichia coli and binds with 0.8 nM affinity to mouse neutrophils. Human neutrophils also bind recombinant KC at a site competitive with human interleukin (IL8) and Gro-alpha/MGSA, consistent with binding at the IL8 type B receptor (IL8RB).

Effect of in vivo desensitization to leukotriene B4 on eosinophil infiltration in response to C5a in guinea-pig skin.

1. The effect of in vivo desensitization to leukotriene B4 (LTB4) on eosinophil infiltration in response to recombinant C5a was examined in guinea-pig skin. 2.