Allelic frequency of the MCP-1 promoter −2518 polymorphism in the Turkish population and in Turkish patients with juvenile rheumatoid arthritis

Association study of MCP-1 promoter polymorphisms with the susceptibility and progression of sepsis

Previous studies have indicated that the monocyte chemo-attractant protein 1 (MCP-1), also referred to as C-C motif chemokine ligand 2 (CCL2), plays a significant role in the pathogenesis of sepsis, and this study investigated the clinical relevance of two MCP-1 gene polymorphisms on sepsis onset and progression. The Multiplex SNaPshot genotyping method was used to detect MCP-1 gene polymorphisms in the Chinese Han population (403 sepsis patients and 400 controls). MCP-1 mRNA expression levels were measured using real-time quantitative PCR, and enzyme-linked immunosorbent assays were used to analyze MCP-1, tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) and interleukin-1 beta (IL-1β) plasma concentrations. The rs1024611 polymorphism analysis showed lower frequencies of minor homozygous genotype (AA) and allele (A) in sepsis patients compared to the healthy controls (19.4% vs. 31.5%, P = 0.0001 and 45.9% vs. 54.8%, P = 0.0004, respectively). And the frequencies of GG genotype and G allele were lower in sepsis patients compared to the controls (19.6% vs. 31.3%, P = 0.0002 and 46.0% vs. 54.5%, P = 0.0007, respectively). The rs1024611 AG/GG and rs2857656 GC/CC genotypes were both overrepresented in patients with severe sepsis (both P = 0.0005) and septic shock (P = 0.010 and P = 0.015, respectively) compared to the patients with mild sepsis. Moreover, among sepsis patients, the rs1024611 AG/GG and rs2857656 GC/CC carriers exhibited significant increases in expression levels of MCP-1 (P = 0.025), TNF-α (P = 0.034) and IL-6 (P = 0.043) compared with the rs1024611 AA or rs2857656 GG carriers. This study provides valuable clinical evidence that the MCP-1/CCL2 polymorphisms rs1024611 and rs2857656 are associated with sepsis susceptibility and development. We conclude that MCP-1/CCL2 plays a significant role in the pathogenesis of sepsis, which has potentially important therapeutic implications.

The -2518 A/G polymorphism in the monocyte chemoattractant protein 1 gene (MCP-1) is associated with an increased risk of rheumatoid arthritis in Argentine patients

The aim of this study was to analyze the influence of nucleotide transition (G/A) in position -2518 of the MCP-1 gene related to the susceptibility of developing RA. Two hundred twenty-three consecutive RA patients according to 2010 ACR/EULAR criteria were included; 120 healthy subjects were used as controls. MCP-1 -2518 A/G polymorphism (AG + GG) was present in 162 (72.6 %) RA patients and in 63 (52.5 %) healthy subjects [OR 2.44 (IC95% 1.53-3.88, p = 0.0002)]; associations for heterozygotes and homozygotes were OR 1.92 (IC95% 1.19-3.15, p = 0.001) and OR 5.19 (IC95% 2.34-11.51, p = 0.001), respectively. In Argentine patients, MCP-1 gene polymorphism confers susceptibility for developing RA.

The associations between the MCP-1 -2518 A/G polymorphism and ischemic heart disease and ischemic stroke: a meta-analysis of 28 research studies involving 21,524 individuals

Epidemiologic studies have been performed to explore the relationship between MCP-1 polymorphism and ischemic heart disease (IHD) and ischemic stroke (IS). But, the results are not consistent. Because of the poor effect of each individual study, we've performed a systematic review and a meta-analysis. A comprehensive search was carried out from PubMed, Embase, Foreign Medical Journal Service (FMJS), China National Knowledge Infrastructure and Wanfang Data. Odds ratios (OR) with 95% confidence interval (CI) were used to evaluate the strength of associations between the MCP-1 A-2518G polymorphism (rs1024611) and IHD and IS susceptibilities. The pooled OR was calculated by the allelic model (G vs A), the additive model (GG vs AA), the dominant model (GG+GA vs AA) and the recessive model (GG vs AA+GA), respectively. The homogeneity among studies was checked using Cochrane Q statistic. The stability of results was checked by one-way sensitivity analysis. The publication bias between studies was examined by Begg's funnel plots and Egger's test. 28 eligible case-control studies met all the criteria and were involved in the present meta-analysis, including a total of 8,901 cases and 12,623 controls. Overall, the MCP-1 A-2518G polymorphism was significantly associated with the IHD susceptibility. The pooled OR was 1.27 (95% CI 1.09-1.48, P = 0.002) in the dominant model, 1.20 (95% CI 1.07-1.35, P = 0.001) in the allelic model, 1.25 (95% CI 1.05-1.50, P = 0.015) in the recessive model and 1.39 (95% CI 1.10-1.75, P = 0.005) in the additive model. At the same time, the MCP-1 A-2518G polymorphism was significantly associated with the IS susceptibility. The pooled OR was 1.72 (95% CI 1.12-2.65, P = 0.013) in the dominant model, 1.39 (95% CI 1.12-1.74, P = 0.003) in the allelic model, 1.59 (95% CI 1.30-1.93, P = 0.000) in the recessive model, and 2.33 (95% CI 1.76-3.08, P = 0.000) in the additive model, respectively. No significant publication bias was found in the present meta-analysis. The results of the present meta-analysis suggest that MCP-1 gene A-2518G polymorphism may be associated with the IHD and IS susceptibilities. But the positive result exists in relatively small sample size subgroup.

RANTES, MCP-1 chemokines and factors describing rheumatoid arthritis

The MCP-1/CCL2 as well as RANTES/CCL5 chemokines are potent chemoattractants involved in immunoregulatory and inflammatory processes of rheumatoid arthritis. Recent studies demonstrated elevated levels of MCP-1 and RANTES in plasma, synovial fluid, and the synovial tissue of patients with RA. To examine the relationship among MCP-1 and RANTES single nucleotide polymorphisms and circulating levels and rheumatoid arthritis (RA), a total of 156 RA patients and 125 controls were recruited into the study. An association of -855 C/G MCP-1 polymorphism to IgM RF within the RA patients was observed. The lowest circulating levels of RANTES were observed in the AA variant of RANTES -403 G/A polymorphism. Furthermore, an association of -403 AA variant to circulating levels of IL-15 and IL-10 was found. No associations of factors describing rheumatoid arthritis (RFs, ANA, anti-CCP-positive/negative, DAS 28 score and number of swollen joints) with MCP-1 levels, genotype distribution, allelic frequencies and/or frequencies of haplotypes composed of all three studied polymorphisms in promoter region of MCP-1, and RANTES polymorphism were observed. We conclude that the RANTES promoter polymorphism is associated to circulating levels of RANTES, IL15 and IL10. However, our findings suggest that polymorphisms in the MCP-1 and RANTES gene promoters do not contribute significantly to the interindividual RA susceptibility and/or severity in Caucasians.

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.

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.

Association of monocyte chemoattractant protein-1 -2518 polymorphism with metabolic syndrome in a South Indian cohort

BACKGROUND

Previous reports have indicated an association of monocyte chemoattractant protein-1 (MCP-1) with risk factors for atherosclerosis and coronary artery disease (CAD). Because some of these risk factors form components of metabolic syndrome, in the present study, we investigated the association of an important promoter region polymorphism of MCP-1, A-2518G, and its serum levels with metabolic syndrome in a South Indian cohort.

METHODS

The study comprised of 126 healthy subjects aged 30-59 years from South India. Subjects were classified on the basis of presence or absence of metabolic syndrome and metabolic syndrome components as per the International Diabetes Federation definition. MCP-1 genotyping was done by polymerase chain reaction restriction fragment-length polymorphism, and serum levels were estimated by enzyme-linked immunosorbent assay.

RESULTS

The MCP-1 -2518G allele frequency in the study population was 32.9% and the mean MCP-1 serum levels were 523 +/- 272.3 pg/mL. Subjects with metabolic syndrome showed an increased presence of the MCP-1 -2518G allele in comparison to those without metabolic syndrome (odds ratio [OR] = 5.03, P = 0.02). The association was related to a higher proportion of this allele in subjects with increased waist circumference (OR = 3.78, P = 0.05).

CONCLUSIONS

The MCP-1 -2518G allele may be contributing to atherosclerosis and CAD by conferring an increased risk to metabolic syndrome and/or obesity.

A comprehensive review of the genetics of juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic arthropathy of childhood which is believed to be influenced by both genetic and environmental factors. The progress in identifying genes underlying JIA susceptibility using candidate gene association studies has been slow. Several associations between JIA and variants in the genes encoding the human leukocyte antigens (HLA) have been confirmed and replicated in independent cohorts. However it is clear that genetic variants outside the HLA also influence susceptibility to JIA. While a large number of non-HLA candidate genes have been tested for associations, only a handful of reported associations such as PTPN22 have been validated. In this review we discuss the principles behind genetic studies of complex traits like JIA, and comprehensively catalogue non-HLA candidate-gene association studies performed in JIA to date and review several validated associations. Most candidate gene studies are underpowered and do not detect associations, and those that do are often not replicated. We also discuss the principles behind genome-wide association studies and discuss possible implications for identifying genes underlying JIA. Finally we discuss several genetic variants underlying multiple clinically distinct autoimmune phenotypes.

The chemokine network. II. On how polymorphisms and alternative splicing increase the number of molecular species and configure intricate patterns of disease susceptibility

In this second review on chemokines, we focus on the polymorphisms and alternative splicings and on their consequences in disease. Because chemokines are key mediators in the pathogenesis of inflammatory, autoimmune, vascular and neoplastic disorders, a large number of studies attempting to relate particular polymorphisms of chemokines to given diseases have already been conducted, sometimes with contradictory results. Reviewing the published data, it becomes evident that some chemokine genes that are polymorphic have alleles that are found repeatedly, associated with disease of different aetiologies but sharing some aspects of pathogenesis. Among CXC chemokines, single nucleotide polymorphisms (SNPs) in the CXCL8 and CXCL12 genes stand out, as they have alleles associated with many diseases such as asthma and human immunodeficiency virus (HIV), respectively. Of CC chemokines, the stronger associations occur among alleles from SNPs in CCL2 and CCL5 genes and a number of inflammatory conditions. To understand how chemokines contribute to disease it is also necessary to take into account all the isoforms resulting from differential splicing. The first part of this review deals with polymorphisms and the second with the diversity of molecular species derived from each chemokine gene due to alternative splicing phenomena. The number of molecular species and the level of expression of each of them for every chemokine and for each functionally related group of chemokines reaches a complexity that requires new modelling algorithms akin to those proposed in systems biology approaches.