A functional promoter polymorphism in monocyte chemoattractant protein-1 is associated with psoriasis

Dendritic Cells and Macrophages in the Pathogenesis of Psoriasis

Psoriasis is a chronic inflammatory skin disease characterized by scaly indurated erythema. This disease impairs patients’ quality of life enormously. Pathological findings demonstrate proliferation and abnormal differentiation of keratinocytes and massive infiltration of inflammatory immune cells. The pathogenesis of psoriasis is complicated. Among immune cells, dendritic cells play a pivotal role in the development of psoriasis in both the initiation and the maintenance phases. In addition, it has been indicated that macrophages contribute to the pathogenesis of psoriasis especially in the initiation phase, although studies on macrophages are limited. In this article, we review the roles of dendritic cells and macrophages in the pathogenesis of psoriasis.

Quantile-specific heritability of monocyte chemoattractant protein-1, and relevance to rs1024611-disease interactions

BACKGROUND

Monocyte chemoattractant protein-1 (MCP-1) concentrations are 34% to 47% heritable. Larger -2518 G/A (rs1024611) genotypes differences are reported for: 1) MCP-1 production in stimulated vs. basal cells; and 2) MCP-1 concentrations in diseased (sepsis, brain abscess, hepatitis B virus, Alzheimer's disease, Behcet's disease, and systemic lupus erythematosus) vs. healthy patients. Those results suggest that the -2518 G/A effect size may depend on whether the phenotype is high or low relative to its distribution (quantile-dependent expressivity).

METHOD

To test whether quantile-dependent expressivity applies more broadly to genetic influences on MCP-1 concentrations, quantile-specific offspring-parent (β_OP) and full-sib regression slopes (β_FS) were estimated by applying quantile regression to the age- and sex-adjusted serum MCP-1 concentrations of Framingham Heart Study families. Quantile-specific heritabilities were calculated as h² = 2β_OP/(1 + r_spouse) and h²={(1 + 8r_spouseβ_FS)^0.5-1}/(2r_spouse)).

RESULTS

Heritability (h² ± SE) of MCP-1 concentrations increased from 0.15 ± 0.05 at the 10th percentile of the MCP-1 distribution, 0.23 ± 0.04 at the 25th, 0.32 ± 0.05 at the 50th, 0.43 ± 0.07 at the 75th, and 0.44 ± 0.07 at the 90th percentile, or an 0.0041 ± 0.0009 increase for each one-percent increment in the MCP-1 distribution (P_{linear trend} = 2.4 × 10^-5) when estimated from β_OP, and (P_{linear trend} = 7.7 × 10^-9) when estimated from β_FS. Compared to the 10th percentile, β_OP-estimated h² was 3-fold greater at the 90th percentile (P_difference = 0.0003), and 6.9-fold greater when estimated from β_FS (P_difference = 3.3 × 10^-6). Re-analysis of in vivo comparison of MCP-1 concentrations in controls vs. patients with MCP-1-elevating conditions, and in vitro studies of MCP-1 production in basal vs. stimulated cells, show rs1024611 genotypes differences that were consistent with quantile-dependent expressivity.

CONCLUSION

The heritability of circulating MCP-1 concentrations is quantile-dependent.

Macrophages in dermatology: pathogenic roles and targeted therapeutics

The field of macrophage biology is rapidly growing. Recent studies have shifted focus from classic wound healing roles to newly identified roles in dermatologic pathology. These studies have identified pathogenic roles of macrophages in relatively common conditions, such as psoriasis, skin cancer, and cutaneous T-cell lymphoma. Selective depletion of these cells or their associated cytokines leads to improved clinical outcome. Herein, we review recent animal and human studies that have elucidated novel pathogenic roles of macrophages in conditions frequently encountered by dermatologists and discuss clinically relevant macrophage-targeted therapies.

Monocyte Chemoattractant Protein-1 in Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis: Biomarker Potential and Association with Polymorphisms in the MCP-1 and the CC Chemokine Receptor-2 Gene

Antineutrophil cytoplasmic autoantibody- (ANCA-) associated vasculitis (AAV) are relapsing-remitting disorders with unpredictable prognosis. There is a need of biomarkers for distinguishing which patients will have a more severe outcome and also for predicting relapses in disease activity. This study confirms the previous results of urinary MCP-1 (uMCP-1) as a prognostic marker and explores its potential as a marker of disease activity. Method. 114 patients with AAV were followed regularly between 2002 and 2011 at Skåne University Hospital. Urine samples, blood samples, and clinical status were registered. The urine samples were analyzed in an in-house-developed ELISA. PCR-RLFP was used to analyze the MCP-1 and CCR2 genes. Results. Patients with severe prognosis had significantly higher levels of uMCP-1 compared to patients with nonsevere prognosis and healthy controls. Patients with renal damage had higher levels compared to patients who did not have renal damage. There was also a tendency of higher uMCP-1 levels in active disease as compared to remission. AA in the -2518 position in the MCP-1 gene was associated with a more severe outcome compared to the A/G or the G/G genotype. The A/A genotype were also associated with higher levels of uMCP-1. No significant associations were seen for the CCR2-V64I. Conclusion. This study confirmed the connection between high uMCP-1 levels and poor prognosis and also disease activity. It also suggests an association of the A/A genotype at position -2518 in the MCP-1 gene and poor prognosis in AAV. uMCP-1 is clearly a candidate biomarker of potential clinical value. The A/A genotype association needs further evaluation.

A functional SNP MCP-1 (-2518A/G) predispose to renal disorder in Indian Systemic Lupus Erythematosus patients

Systemic Lupus Erythematosus (SLE) is a clinically heterogeneous chronic, inflammatory autoimmune disorder that affects multiple organs where exact etiology of the disease is not yet clearly understood. Various evidences suggest that genetic polymorphisms in inflammatory mediators like cytokines and chemokines may influence development of the disease. Here, we investigated whether functional polymorphism at the Monocyte Chemoattractant Protein-1 (MCP-1) regulatory region associates with disease phenotype in Indian SLE patients. This case control study included 200 SLE patients and 201 ethnically matched healthy controls. Genotyping of MCP-1 (-2518 A/G) polymorphism was performed using PCR-RFLP method. Serum MCP-1 levels were detected by bead-based multiplex immunoassay. Serum MCP-1 levels were found to be higher in patients compared with healthy individuals (p<0.0001). A significant difference for MCP-1G allele frequency (OR=1.9, 95%CI=1.4-2.6, p<0.0001) was observed among SLE patients against healthy individuals. A significant difference in the distribution of MCP-1 -2518GG (OR=3.0, 95%CI=1.4-6.7, p=0.0041) and AG+GG genotypes (OR=2.0, 95%CI=1.4-3.0, p=0.0005) was also noted among SLE patients when compared with healthy individuals. A significant association was observed between A/G and G/G versus A/A genotypes with renal manifestations (p<0.0001, Pc<0.001). Serum MCP-1 levels in active LN patients were found to be significantly higher than inactive LN (p=0.0059), mild LN (p=0.0061) as well as non-LN patients (p=0.0001). These findings suggest that -2518G allele of MCP-1 -2518 A/G polymorphism is associated with renal disorders and may influence MCP-1 gene expression among Indian SLE patients.

-2518 A/G MCP-1 but not -403 G/A RANTES gene polymorphism is associated with enhanced risk of basal cell carcinoma

Introduction

Polymorphic variants of MCP-1 and RANTES genes and their protein serum levels have been implicated in the increased risk and severity of several malignancies. However, the subject has not been explored in basal cell carcinoma (BCC) patients so far.

Aim

To investigate the association between monocyte chemoattractant protein 1 (MCP-1) (–2518 A/G) and RANTES (–403 G/A) polymorphism and risk and clinical course of BCC.

Material and methods

The study group consisted of 150 unrelated patients with BCC and 140 healthy, unrelated, age- and sex-matched volunteers. The polymorphisms were analysed using the amplification refractory mutation system polymerase chain reaction method (ARMS-PCR) and single specific primer-polymerase chain reaction (SSP-PCR). Serum cytokine levels were measured with ELISA.

Results

The presence of the MCP-1 –2518 GG genotype was statistically more frequent in BCC patients and it increased the risk of BCC (OR = 2.63, p = 0.003). Genotype –330 GG was statistically more common in patients with less advanced tumours (OR = 2.8, p = 0.017). Monocyte chemoattractant protein 1 serum level was statistically higher with GG genotype. In the BCC group MCP-1 serum levels were decreased. Neither polymorphic variants of RANTES nor the chemokine serum concentration differed significantly between the study groups.

Conclusions

These findings suggest that –2518 A/G MCP-1 polymorphism may be involved in BCC pathogenesis.

Circulating levels of inflammatory cytokines in patients with psoriasis vulgaris of different Chinese medicine syndromes

OBJECTIVE

To investigate whether the serum levels of inflammation-related cytokines might be different between the healthy individuals and the psoriatic patients diagnosed of three varied Chinese medicine (CM) syndromes [blood-stasis syndrome (BSS), blood-dryness syndrome (BDS) and wind-heat syndrome (WHS)].

METHODS

A total of 62 psoriatic patients were recruited and assigned to 3 groups according to their CM syndromes, including 27 patients of BSS, 21 of BDS and 14 of WHS. Another 20 sex- and age-matched healthy subjects were enrolled into the control group. Serum concentrations of multiple cytokines, including monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), soluble CD4O ligand (SCD40L), tumor necrosis factor-α (TNF-α), epidermal growth factor (EGF), interleukin-8 (IL-8), interleukin-17 (IL-17), interferon γ inducible protein-10 (IP-10) and vascular endothelial growth factor (VEGF), were measured by a multiplexed flow cytometric assay.

RESULTS

The circulating levels of MIP-1α, TNF-α, IL-8, and IP-10 were significantly increased in the psoriatic patients compared with the healthy controls (P<0.01). Male and female patients tended to have higher serum levels of MCP-1 and IP-10, respectively (P<0.05). Interestingly, compared with the control group, 6 out of the 9 cytokines (MCP-1, MIP-1α, TNF-α, EGF, IL-8 and IP-10) were substantially increased in the BSS group (P<0.05 or P<0.01), whereas only MIP-1α and IL-8 levels were elevated in the BDS group (P<0.05 or P<0.01) concurrent with lowered concentrations of SCD40L and IL-17 (P<0.05). In the WHS group, MIP-1α was the only cytokine whose level was evidently increased (P<0.01), in contrast to IL-17 which was decreased as compared with the control (P<0.05). The psoriatic patients overall owned higher levels of MIP-1α and IL-8 in the circulation which were comparable among the 3 groups of CM syndromes (P<0.01). In contrast, TNF-α level of the BSS group was the highest among the three (P<0.01), followed by the BDS and the WHS groups.

CONCLUSIONS

The expression profiles of cytokines in the circulation might not be necessarily identical for psoriatic patients with different CM syndromes. Accordingly, the serum concentrations of certain cytokines could potentially be used as the ancillary indices for the clinical classification of psoriatic CM syndromes.

Serum monocyte chemoattractant protein-1 is a biomarker in patients with diabetes and periodontitis

INTRODUCTION

The role of serum Monocyte Chemoattractant Protein-1 (MCP-1) as a biomarker of periodontitis is well documented; however, its role in diabetic patients with periodontitis is unknown.

AIM

This study was conducted to determine the presence and concentration of serum MCP-1 in diabetic patients with and without periodontitis and correlate it glycemic status with periodontitis.

MATERIALS AND METHODS

Adult diabetic patients were enrolled and grouped into group I, II, and III based on their glycemic status and serum MCP-1 estimated by ELISA. Linear regression and correlation tests were performed using R statistical software, Medcalc software to observe correlation between the serum MCP-1 and glycated hemoglobin level among different groups.

RESULTS

Serum samples obtained from 37 patients tested positive for MCP-1. Mean serum MCP-1 concentration was highest (482.3 pg/ml) in group III, lowest (149.3 pg/ml) in group I, and intermediate 398.8 pg/ml in group II. Correlation and regression analysis was done between HbA1c and serum MCP-1. A significant positive correlation (P < 0.001) was observed. Serum MCP-1 increased by 37.278 pg/ml for every 1% rise in HbA1c, and the levels were raised in group II and group III than in group I irrespective of their glycemic status. With an HbA1c range of 6.5-6.9% (group II), the serum MCP-1 values cluster around 380-410 pg/ml. Elevated levels of serum MCP-1 (>500 pg/ml) in three subjects corresponded to HbA1c values more than 12.2% (group III).

CONCLUSION

To our knowledge, this is the first study to document serum MCP-1 levels in diabetic patients with periodontitis. Glycemic status influences serum MCP-1, and lack of glycemic control contributes to increased serum MCP-1 levels. Serum MCP-1 may thus serve as a biomarker of inflammation and disease progression in diabetes with periodontitis.

Pharmacogenetics of topical and systemic treatment of psoriasis

Psoriasis is a chronic inflammatory skin disease. The cause of psoriasis is unknown, although genetics may play a key role in its development. Treatment of the disease varies with severity. Topical drugs, such as corticosteroids, coal tar, retinoids and vitamin D analogs, are commonly used to treat mild psoriasis. Phototherapy and systemic drugs, such as calcineurin inhibitors, methotrexate, acitretin and biological drugs, are usually used to treat moderate-to-severe psoriasis. Not all patients respond well to treatment, and some can develop severe adverse effects. Interindividual differences in several genes may explain this variation in response to treatment. Pharmacogenetics and pharmacogenomics can facilitate more personalized medicine and prevent the adverse effects associated with treatment.

Genetics of psoriasis and pharmacogenetics of biological drugs

Psoriasis is a chronic inflammatory disease of the skin. The causes of psoriasis are unknown, although family and twin studies have shown genetic factors to play a key role in its development. The many genes associated with psoriasis and the immune response include TNFα, IL23, and IL12. Advances in knowledge of the pathogenesis of psoriasis have enabled the development of new drugs that target cytokines (e.g., etanercept, adalimumab, and infliximab, which target TNFα, and ustekinumab, which targets the p40 subunit of IL23 and IL12). These drugs have improved the safety and efficacy of treatment in comparison with previous therapies. However, not all patients respond equally to treatment, possibly owing to interindividual genetic variability. In this review, we describe the genes associated with psoriasis and the immune response, the biological drugs used to treat chronic severe plaque psoriasis, new drugs in phase II and III trials, and current knowledge on the implications of pharmacogenomics in predicting response to these treatments.

MCP-1 in psoriatic patients: effect of biological therapy

BACKGROUND

Monocyte chemoattractant protein-1 (MCP-1) is a chemokine locally and systemically augmented in psoriasis. A single nucleotide polymorphism in MCP-1 promoter region -2518A→G is associated with higher gene expression.

OBJECTIVE

The aim was to evaluate MCP-1 plasma level in psoriatic patients and to relate any association in plasmatic and cutaneous MCP-1 with clinical improvement due to biological drugs.

METHODS

Blood samples were obtained from: (i) 30 Caucasian patients with psoriasis and 10 controls, for determining MCP-1 plasma concentrations and -2518A→G polymorphism occurrence, (ii) 16 psoriatic patients treated by anti-tumor necrosis factor-α (TNF-α) adalimumab/etanercept or by anti-CD-11 efalizumab, before and after 2 months of treatment. Moreover, biopsies were performed on lesional skin of five patients treated with anti-TNF-α. MCP-1 plasma concentration and cutaneous expression were determined by ELISA and qRT-PCR.

RESULTS

MCP-1 plasma level was significantly increased in psoriatic patients. -2518A→G polymorphism was similarly distributed in patients and controls and unrelated to MCP-1 plasma level or to Psoriasis Area and Severity Index. All patients receiving biological drugs showed significant clinical improvement. Anti-TNF-α therapy moderately reduced MCP-1 plasma concentration and robustly decremented MCP-1 expression in lesional skin.

CONCLUSION

MCP-1 should be a potential local inflammatory marker in psoriatic patients to assess disease severity and anti-TNF-α treatment efficacy.

IFNβ autocrine feedback is required to sustain TLR induced production of MCP-1 in macrophages

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MCP-1 mRNA levels and protein secretion in macrophages are induced by TLR activation.

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In response to LPS, the initial induction of MCP-1 mRNA is IFNβ independent.

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The sustained production of MCP-1 by LPS requires an IFNβ mediated feedback loop.

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The sustained production of MCP-1 by poly IC also requires IFNβ.

Chemokines, including MCP-1, are crucial to mounting an effective immune response due to their ability to recruit other immune cells. We show that sustained LPS or poly(I:C)-stimulated MCP-1 production requires an IFNβ-mediated feedback loop. Consistent with this, exogenous IFNβ was able to induce MCP-1 transcription in the absence of other stimuli. Blocking IFNβ signaling with Ruxolitinib, a JAK inhibitor, inhibited MCP-1 transcription. The MCP-1 promoter contains potential STAT binding sites and we demonstrate that STAT1 is recruited upon IFNβ stimulation. Furthermore we find that IL-10 knockout increases MCP-1 production in response to LPS, which may reflect an ability of IL-10 to repress IFNβ production. Overall, these results show the importance of the balance between IFNβ and IL-10 in the regulation of MCP-1.

The rs1024611 regulatory region polymorphism is associated with CCL2 allelic expression imbalance

CC chemokine ligand 2 (CCL2) is the most potent monocyte chemoattractant and inter-individual differences in its expression level have been associated with genetic variants mapping to the cis-regulatory regions of the gene. An A to G polymorphism in the CCL2 enhancer region at position -2578 (rs1024611; A>G), was found in most studies to be associated with higher serum CCL2 levels and increased susceptibility to a variety of diseases such as HIV-1 associated neurological disorders, tuberculosis, and atherosclerosis. However, the precise mechanism by which rs1024611influences CCL2 expression is not known. To address this knowledge gap, we tested the hypothesis that rs1024611G polymorphism is associated with allelic expression imbalance (AEI) of CCL2. We used haplotype analysis and identified a transcribed SNP in the 3'UTR (rs13900; C>T) can serve as a proxy for the rs1024611 and demonstrated that the rs1024611G allele displayed a perfect linkage disequilibrium with rs13900T allele. Allele-specific transcript quantification in lipopolysaccharide treated PBMCs obtained from heterozygous donors showed that rs13900T allele were expressed at higher levels when compared to rs13900C allele in all the donors examined suggesting that CCL2 is subjected to AEI and that that the allele containing rs1024611G is preferentially transcribed. We also found that AEI of CCL2 is a stable trait and could be detected in newly synthesized RNA. In contrast to these in vivo findings, in vitro assays with haplotype-specific reporter constructs indicated that the haplotype bearing rs1024611G had a lower or similar transcriptional activity when compared to the haplotype containing rs1024611A. This discordance between the in vivo and in vitro expression studies suggests that the CCL2 regulatory region polymorphisms may be functioning in a complex and context-dependent manner. In summary, our studies provide strong functional evidence and a rational explanation for the phenotypic effects of the CCL2 rs1024611G allele.

No association of monocyte chemoattractant protein-1 -2518 A/G polymorphism with the risk of primary glomerulonephritis in the Polish population

Various studies have indicated that chemokines such as monocyte chemotactic protein-1 (MCP-1) play an important role in the pathogenesis of primary glomerulonephritis (GN) and other glomerular diseases. Moreover, patients with primary GN display aberrant galactosylation of the O-linked carbohydrate moieties of IgA. Therefore, we analysed the distribution of the functional MCP-1 -2518 A > G (rs 1024611) and 1 beta 1,3-galactosyltransferase (C1GalT1) 1365 A > G (rs1047763) polymorphic variants in patients with primary GN (n = 144) and controls (n = 437) in a sample of the Polish population. We did not find a significant difference in the prevalence of the MCP-1 -2518 A > G and C1GalT1 1365 A > G polymorphisms in patients with primary GN and healthy individuals. Odds Ratio (OR) for GN patients with the MCP-1 -2518 GG genotype was 0.869 (95% CI = 0.410-1.840, P = 0.7130), and OR of the -2518 GG and -2518AG genotypes was 1.004 (95% CI = 0.689-1.464, P = 0.9836). OR for C1GalT1 1365AA genotype was 0.484 (95% CI = 0.181-1.293, P = 0.1402) and OR of the 1365AA and 1365AG genotypes was 0.839 (95% CI = 0.573-1.228, P = 0.3651). We also did not observe a difference in the distribution of alleles between patients and controls. The MCP-1 -2518 G allelic OR was 0.976 (95% CI = 0.725-1.314, P = 0.8744). The OR for the C1GalT1 1365A allele was 0.816 (95% CI = 0.596-1.118, P = 0.205). Moreover, there was no significant association between the MCP-1 -2518 A > G and C1GalT1 1365 A > G genotypes with different morphological types of primary GN or clinical manifestations. Our observations indicate that the MCP-1 -2518 A > G and C1GalT1 1365 A > G polymorphisms might not be a risk factor in the incidence of primary GN in the Polish population.

Erratum to "Neutrophil-dominant psoriasis-like skin inflammation induced by epidermal-specific expression of Raf in mice" [J. Dermatol. Sci. 58 (2010) 28-35]

BACKGROUND

Raf is one of the downstream effectors of Ras GTPases. The induction of Raf in the epidermis causes the proliferation of keratinocytes and epidermal hyperplasia. However, skin inflammation accompanying Ras-induced epidermal reactions has not been fully delineated.

OBJECTIVE

The aim of this study was to characterize inflammatory reactions induced by epidermal-specific Raf expression and to elucidate its role in skin inflammation.

METHODS

K14-Raf:ER transgenic mice, in which the 4-hydroxytamoxifen (4OHT)-responsive mutant estrogen receptor (ER) ligand binding domain-Raf fusion gene was expressed under control of the keratin 14 promoter, were used to characterize inflammatory reactions induced by Raf expression in the epidermis.

RESULTS

A single topical application of 4OHT induced the expression of phosphorylated extracellular signal-related kinase 1/2 and elicited neutrophil-dominant inflammatory infiltrates in the skin. The Raf expression also rapidly induced the production of several cytokines and chemokines, including VEGF and CXCL1, by keratinocytes and inmouse skin in vivo. Furthermore, CD4-positive cells from regional lymph nodes had the potential to differentiate into IFNg- and IL17-producing cells. Treatment with an anti-Gr-1 antibody diminished the Raf-induced cutaneous inflammation and partially reversed the epidermal hyperplasia and hyperkeratosis.

CONCLUSION

Activation of the Raf signaling pathway is involved in the epidermal hyperplasia and the neutrophil-dominant cutaneous inflammatory reactions which are characteristics of psoriasis.

Monocyte chemoattractant protein-1 -2518 A/G single nucleotide polymorphism might be associated with renal disease and thrombocytopenia of SLE

There is conflicting evidence on the contribution of the MCP-1 -2518 A>G (rs 1024611) polymorphism to SLE incidence and clinical manifestations. We examined the prevalence of the MCP-1 -2518 A>G polymorphism in SLE patients (n = 199) and controls (n = 250) in Poland. We did not observe a significant difference in the distribution of MCP-1 -2518 A>G polymorphic variants in patients with SLE and healthy individuals. However, we found an association between the GG versus AG and AA genotypes as well as the AG and GG versus AA genotypes with renal manifestations of SLE OR = 3.614 (1.123-11.631, P = 0.0345) and OR = 2.297 (1.301-4.057, P = 0.0046), respectively. We also observed that the MCP-1 AG and GG -genotypes contribute to the occurrence of thrombocytopenia in SLE patients OR = 2.618 (1.280-5.352, P = 0.0089). Our observations indicate that either MCP-1 -2518 G variant can be associated with some clinical findings in patients with SLE.

Neutrophil-dominant psoriasis-like skin inflammation induced by epidermal-specific expression of Raf in mice

BACKGROUND

Raf is one of the downstream effectors of Ras GTPases. The induction of Raf in the epidermis causes the proliferation of keratinocytes and epidermal hyperplasia. However, skin inflammation accompanying Ras-induced epidermal reactions has not been fully delineated.

OBJECTIVE

The aim of this study was to characterize inflammatory reactions induced by epidermal-specific Raf expression and to elucidate its role in skin inflammation.

METHODS

K14-Raf:ER transgenic mice, in which the 4-hydroxytamoxifen (4OHT)-responsive mutant estrogen receptor (ER) ligand binding domain-Raf fusion gene was expressed under control of the keratin 14 promoter, were used to characterize inflammatory reactions induced by Raf expression in the epidermis.

RESULTS

A single topical application of 4OHT induced the expression of phosphorylated extracellular signal-related kinase 1/2 and elicited neutrophil-dominant inflammatory infiltrates in the skin. The Raf expression also rapidly induced the production of several cytokines and chemokines, including VEGF and CXCL1, by keratinocytes and in mouse skin in vivo. Furthermore, CD4-positive cells from regional lymph nodes had the potential to differentiate into IFN gamma- and IL17-producing cells. Treatment with an anti-Gr-1 antibody diminished the Raf-induced cutaneous inflammation and partially reversed the epidermal hyperplasia and hyperkeratosis.

CONCLUSION

Activation of the Raf signaling pathway is involved in the epidermal hyperplasia and the neutrophil-dominant cutaneous inflammatory reactions which are characteristics of psoriasis.

Duffy antigen receptor for chemokines (Darc) polymorphism regulates circulating concentrations of monocyte chemoattractant protein-1 and other inflammatory mediators

To identify the genetic basis of circulating concentrations of monocyte chemoattractant protein-1 (MCP-1), we conducted genome-wide association analyses for MCP-1 in 3 independent cohorts (n = 9598). The strongest association was for serum MCP-1 with a nonsynonymous polymorphism, rs12075 (Asp42Gly) in DARC, the gene for Duffy antigen receptor for chemokines, a known vascular reservoir of proinflammatory cytokines (minor allele frequency, 45.6%; P < 1.0 * 10(-323)). This association was supported by family-based genetic linkage at a locus encompassing the DARC gene (genome-wide P = 8.0 * 10(-13)). Asp42Gly accounted for approximately 20% of the variability in serum MCP-1 concentrations and also was associated with serum concentrations of interleukin-8 and RANTES. While exploring a lack of association between this polymorphism and EDTA plasma MCP-1 concentrations (P = .82), we determined that both clotting and exogenous heparan sulfate (unfractionated heparin) released substantial amounts of MCP-1 from Darc. Quantitative immunoflow cytometry failed to identify meaningful Asp42Gly-associated differences in Darc expression, suggesting that a functional change is responsible for the differential cytokine binding. We conclude that Asp42Gly is a major regulator of erythrocyte Darc-mediated cytokine binding and thereby the circulating concentrations of several proinflammatory cytokines. We have also identified for the first time 2 mechanisms for the release of reservoir chemokines with possible clinical implications.

The source matters: no impact of the CCL2/MCP-1-1-2518G polymorphism of the donor on renal allograft outcome during the first year after transplantation

Chemokines are involved in the recruitment of inflammatory cells to vascularized allografts. The chemokine CCL2/MCP-1 is expressed during allograft dysfunction, which is associated with the recruitment of inflammatory cells. Both intrinsic renal cells (donor origin) as well as infiltrating inflammatory cells (recipient origin) can be a source of CCL2/MCP-1. We previously demonstrated that the recipient MCP-1-2518G polymorphism is associated with increased CCL2/MCP-1 production by inflammatory cells and decreased renal allograft survival. We evaluated the impact of the MCP-1-2518G polymorphism in donor cells on renal allograft outcomes. We enrolled 252 recipients of kidney allografts in this retrospective study who had received grafts from 152 cadaveric donors. The CCL2/MCP-1 genotype was assessed using genomic DNA isolated from cryopreserved donor splenocytes. Outcome parameters studied were acute biopsy proven rejection (Banff criteria), serum creatinine, and glomerular filtration rate (GFR) at 1 year after transplantation, allograft loss, and death. MCP-1-2518 genotypes were in HW equilibrium. A/A was present in 125 (49.6%), A/G in 107 (42.5%), and G/G in 20 (7.9%) donor kidneys. There were no significant differences in the number of rejection episodes, the number of allograft losses, serum creatinine, GFR, or overall survival 1 year after transplantation. In contrast with the detrimental effect of the CCL2/MCP-1 polymorphism of the recipient, the CCL2/MCP-1 polymorphism of the donor has no impact on the allograft outcome during the first year after transplantation. The impact on the long-term outcomes needs further evaluation.

Terameprocol, a methylated derivative of nordihydroguaiaretic acid, inhibits production of prostaglandins and several key inflammatory cytokines and chemokines

BACKGROUND

Extracts of the creosote bush, Larrea tridentata, have been used for centuries by natives of western American and Mexican deserts to treat a variety of infectious diseases and inflammatory disorders. The beneficial activity of this plant has been linked to the compound nordihydroguaiaretic acid (NDGA) and its various substituted derivatives. Recently, tetra-O-methyl NDGA or terameprocol (TMP) has been shown to inhibit the growth of certain tumor-derived cell lines and is now in clinical trials for the treatment of human cancer. In this report, we ask whether TMP also displays anti-inflammatory activity. TMP was tested for its ability to inhibit the LPS-induced production of inflammatory lipids and cytokines in vitro. We also examined the effects of TMP on production of TNF-alpha in C57BL6/J mice following a sublethal challenge with LPS. Finally, we examined the molecular mechanisms underlying the effects we observed.

METHODS

RAW 264.7 cells and resident peritoneal macrophages from C57BL6/J mice, stimulated with 1 mug/ml LPS, were used in experiments designed to measure the effects of TMP on the production of prostaglandins, cytokines and chemokines. Prostaglandin production was determined by ELISA. Cytokine and chemokine production were determined by antibody array and ELISA.Western blots, q-RT-PCR, and enzyme assays were used to assess the effects of TMP on expression and activity of COX-2.q-RT-PCR was used to assess the effects of TMP on levels of cytokine and chemokine mRNA.C57BL6/J mice injected i.p. with LPS were used in experiments designed to measure the effects of TMP in vivo. Serum levels of TNF-alpha were determined by ELISA.

RESULTS

TMP strongly inhibited the production of prostaglandins from RAW 264.7 cells and normal peritoneal macrophages. This effect correlated with a TMP-dependent reduction in levels of COX-2 mRNA and protein, and inhibition of the enzymatic activity of COX-2.TMP inhibited, to varying degrees, the production of several cytokines, and chemokines from RAW 264.7 macrophages and normal peritoneal macrophages. Affected molecules included TNF-alpha and MCP-1. Levels of cytokine mRNA were affected similarly, suggesting that TMP is acting to prevent gene expression.TMP partially blocked the production of TNF-alpha and MCP-1 in vivo in the serum of C57BL6/J mice that were challenged i.p. with LPS.

CONCLUSION

TMP inhibited the LPS-induced production of lipid mediators and several key inflammatory cytokines and chemokines, both in vitro and in vivo, raising the possibility that TMP might be useful as a treatment for a variety of inflammatory disorders.

Moving targets: cell migration inhibitors as new anti-inflammatory therapies

The pharmaceutical industry has targeted various types of molecules to subdue inflammatory diseases. Drugs that disrupt cell migration appear particularly promising in clinical trials and in many animal models of inflammatory disease. Cell migration inhibitors not only interfere with migration of cells to a tissue, but also can affect other necessary processes such as mediator release and angiogenesis. However, the question is whether drugs that target adhesion molecules or chemoattractant receptors will prove superior to drugs that target other molecular types. This review proclaims the virtues of targeting cell migration-related molecules for development of new anti-inflammatory and anti-tumor based drugs. It is likely that cell migration inhibitors will transform the way in which many human inflammatory diseases and cancers are treated.