Yeminia Valle

Macrophage migration inhibitory factor (MIF): Genetic evidence for participation in early onset and early stage rheumatoid arthritis

Macrophage migration inhibitory factor (MIF) is an upstream pro-inflammatory cytokine that is associated with the pathogenesis of autoimmune inflammatory diseases including rheumatoid arthritis (RA). Two polymorphisms in the upstream region exist in the MIF gene and are associated with RA susceptibility or severity in different populations. In this case-control study, we investigated whether MIF polymorphisms are associated with RA susceptibility or activity in a western Mexican population .The relationship of MIF levels with clinical features of disease also was assessed. Genotyping of the -794 CATT5-8 (rs5844572) and the -173 G>C (rs755622) polymorphisms was performed by PCR and PCR-RFLP respectively on 226 RA patients and 210 healthy subjects. Serum MIF levels were determined by ELISA. We found a significant association between the -794 CATT5-8 6,7 MIF genotype with RA. Moreover, we detected an association between the -794 CATT7 allele with early onset RA. The -794 CATT7 and -173(*)C alleles, which are in linkage disequilibrium, were associated with high disease activity on RA patients. A positive correlation between circulating MIF levels and C-reactive protein, erythrocyte sedimentation rate, rheumatoid factor, anti-citrullinated protein/peptides antibodies and TNFα was detected. MIF levels appear to be associated with disease progression rather than disease activity, which is distinct from the established relationship between disease activity and TNFα levels. In conclusion, the MIF gene and protein are associated with RA in a western Mexican population, with a main contribution onto early onset and early stages of disease.

The +49A>G CTLA-4 polymorphism is associated with rheumatoid arthritis in Mexican population.

BACKGROUNDnThe Cytotoxic T lymphocyte antigen (CTLA-4) is one of the major susceptibility genes associated with autoimmune diseases. Susceptibility to rheumatoid arthritis (RA) is determined by both environmental and genetic factors. The genetic contribution approaches 50-60%. The association between RA with the +49A>G CTLA-4 polymorphism in the Mexican population was investigated.nnnMETHODSnThe polymerase chain reaction-restriction fragment was used to amplify the +49A>G CTLA-4 polymorphism in RA patients and healthy subjects (HS).nnnRESULTSnWe analyzed the association between the +49A>G CTLA-4 polymorphism and RA. The G allele frequency was higher in RA patients than HS (46.8 vs 37.7%, OR=1.45, p=0.01). RA patients carrying the A/G genotype were significantly more likely to be positive to CRP and RF. There was no evidence of an association between SNP genotypes and the clinical characteristics of rheumatoid arthritis.nnnCONCLUSIONSnThe +49A>G CTLA-4 polymorphism is a genetic marker of susceptibility for RA in western Mexican population.

Serum levels of macrophage migration inhibitory factor are associated with rheumatoid arthritis course

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease of unknown etiology. Many cytokines have been found to be associated with RA pathogenesis and among them is macrophage migration inhibitory factor (MIF). The aim of this study was to determine whether MIF serum levels are associated with RA course, clinical activity, and clinical biomarkers of the disease. MIF levels were determined in serum samples of 54 RA patients and 78 healthy subjects (HS) by enzyme-linked immunosorbent assay (ELISA). Disease activity was evaluated using the DAS28 score. Patients were subgrouped according to disease activity and years of evolution of disease. Statistical analysis was carried out by SPSS 10.0 and GraphPad Prism 5 software. RA patients presented increased levels of MIF as compared to HS. MIF levels were raised on early stages of RA and tend to decrease according to years of evolution. Moreover, MIF levels positively correlated with rheumatoid factor in RA patients and with C reactive protein in all individuals studied. Our findings suggest that MIF plays a role in early stages of RA.

The −319C/+49G/CT60G Haplotype of CTLA-4 Gene Confers Susceptibility to Rheumatoid Arthritis in Mexican Population

Several single nucleotide polymorphisms (SNPs) within the CTLA-4 gene and elevated serum levels of soluble CTLA-4 (sCTLA-4) have been associated with autoimmunity including rheumatoid arthritis (RA). In this case–control study, we evaluated the relationship between the −319C/T (rs5742909) and CT60 G/A (rs3087243) SNPs and sCTLA-4 levels in 200 RA patients and 200 control subjects (CS) from Western Mexico. Both SNPs were genotyped with the polymerase chain reaction–restriction fragment length polymorphism technique and the sCTLA-4 levels were quantified using an enzyme-linked immunosorbent assay kit. In addition, we performed a haplotype analysis, including our previous data of the +49A/G (rs231775) SNP. The G/A genotype of the rs3087243 SNP was associated with a decreased risk of RA [odd ratio (OR) 0.61, 95xa0% confidence interval (CI) 0.38–0.96, pxa0=xa00.024]. This protection was also observed in the negative anti-cyclic citrullinated peptide group of RA carriers of the A allele (OR 0.48, 95xa0% CI 0.22–1.05, pxa0=xa00.042). On the contrary, we identified the −319C/+49G/CT60G haplotype of CTLA-4 gene as a risk factor for RA (OR 1.69, 95xa0% CI 1.13–2.52, pxa0=xa00.01). The sCTLA-4 levels were not associated with RA (pxa0=xa00.377), but were correlated with the functional disability of these patients (rxa0=xa00.282, pxa0=xa00.012). However, in CS the C/T genotype of the rs5742909 SNP, as well as the G/G and G/A genotypes of the rs3087243 SNP were associated with higher sCTLA-4 levels (pxa0<xa00.001). In conclusion, our results suggest that the −319C/+49G/CT60G haplotype of CTLA-4 gene is a genetic marker of susceptibility to RA in Western Mexico, whereas the rs3087243 SNP confers protection against this disease. Moreover, both SNPs showed an effect on the sCTLA-4 production in our control population. However, further studies are required to evaluate the role of sCTLA-4 in RA, as well as the molecular and functional basis of the association between both CTLA-4 gene SNPs and soluble levels of CTLA-4 in CS.

Circulating TNFRI and TNFRII levels correlated with the disease activity score (DAS28) in rheumatoid arthritis

Objective: To measure levels of soluble tumour necrosis factor alpha (TNFα) receptor type I (sTNFRI) and type II (sTNFRII) in order to correlate them with C-reactive protein (CRP), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and disease activity score (DAS28) in RA patients. Methods: We recruited 41 RA patients classified according to American College of Rheumatology (ACR) criteria and 38 healthy subjects (HS). sTNFRI and sTNFRII were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Clinical activity in RA patients was evaluated using the Disease Activity Score using 28 joint counts (DAS28). The statistical analysis was realized using SPSS version 10.0. Results: Soluble TNFRI and TNFRII levels were higher in RA patients (p = 0.04 and 0.001, respectively) than HS. Serum levels of sTNFRI correlated with sTNFRII (r = 0.699, p < 0.0001). sTNFRII correlated with DAS28 (r = 0.375, p = 0.017), RF (r = 0.505, p = 0.004), and ESR (r = 0.323, p = 0.042). Conclusion: The increased levels of both sTNFRI and sTNFRII suggest a secondary event related to the inflammatory state observed in RA, whereas the correlation of sTNFRII with RF, ESR, and DAS28 reflects the preferential TNFRII shedding induced by TNFα. sTNFRII may be useful as an additional inflammatory marker in RA.

Association of the -1031T>C polymorphism and soluble TNF-α levels with Acute Coronary Syndrome.

INTRODUCTIONnInflammation has gained a pivotal role in the pathophysiology of Acute Coronary Syndrome (ACS). TNF-α is a pro-inflammatory cytokine that could be a potential biomarker in ACS due to its multiple functions. The rs1799964 TNFA polymorphism (-1031T>C) has been associated with a decrease in gene transcription and cytokine levels.nnnOBJECTIVEnTo determine the association of rs1799964 TNFA polymorphism and TNF-α soluble levels in ACS.nnnMETHODSnA total of 251 patients diagnosed with ACS and 164 individuals without cardiovascular diseases classified as the reference group (RG), were included. The rs1799964 polymorphism was genotyped by PCR-RFLP. Soluble protein levels were determined by ELISA. Statistical analyses were performed using chi square and U-Mann Whitney tests.nnnRESULTSnThe genotype and allele frequencies were different between ACS and RG (OR=0.317, p=0.01; OR=0.688, p=0.03 respectively). ACS patients had higher soluble TNF-α levels compared with the RG (31.08 vs 23.00pg/mL, p<0.001); according genotype significant differences were observed (T/T: 24.06 vs T/C: 34.95pg/mL, p=0.0001) in patients. In the RG, T/T carriers showed discrete lower levels than C/C genotype (22.14 vs 27.83pg/mL, p=0.04).nnnCONCLUSIONSnThe -1031C allele of the TNFA polymorphism confers protection for the development of ACS. The T/C genotype carriers had higher TNF-α serum levels compared to the T/T genotype in ACS. In addition, the -1031T>C TNFA polymorphism was associated with dyslipidemia in ACS in a Western Mexican population.

Association of interleukin-10 promoter haplotypes with disease susceptibility and IL-10 levels in Mexican patients with systemic lupus erythematosus

AbstractnSystemic lupus erythematosus (SLE) is the prototype autoimmune rheumatic disease. The etiology of this disease is incompletely understood; however, environmental factors and genetic predisposition are involved. Cytokine-mediated immunity plays a crucial role in the pathogenesis of SLE. We investigate the association of interleukin-10 (IL-10) promoter polymorphisms and their haplotypes in SLE patients from the western Mexico. One hundred and twenty-five SLE patients fulfilling the 1997 ACR criteria and 260 unrelated healthy subjects (HS), both Mexican mestizos, were genotyped for IL-10 −1082A>G, −819C>T, and −592C>A polymorphisms. Haplotypes were inferred using the expectation–maximization algorithm, then allele and haplotype distributions were compared between patients and HS, as well as patients with different clinical variables. We identified at −1082, −819, and −592 four predominant haplotypes ACC (43.70xa0% in patients vs 46.55xa0% in HS), ATA (21.45 vs 22.97xa0%), GCC (16.28 vs 14.21xa0%), and GTA (14.12 vs 14.12xa0%). The ATC haplotype was more frequent in SLE respect to HS, suggesting a risk effect (3.23 vs 1.05xa0%; OR 3.55, CI 1.14–11.11; pxa0=xa00.0293). SLE patient carriers of −592 CC genotype as well as the dominant model of inheritance showed higher sIL-10 respect to AA genotype, suggesting that −592 C allele is associated with increased production of the cytokine (pxa0<xa00.05). The ACC haplotype had higher IL-10 serum levels and higher values of Mexican version of the Systemic Lupus Erythematosus Disease Activity Index compared with the other haplotype carriers; however, no association was found regarding autoantibodies. Our data suggest that the IL-10 promoter haplotypes play an important role in the risk of developing SLE and influence the production of IL-10 in Mexican population. Nevertheless, further studies are required to analyze the expression of mRNA as well as to investigate the interacting epigenetic factors that could help to define the true contribution of this marker in SLE pathogenesis.

Association between the -794 (CATT)5-8 MIF gene polymorphism and susceptibility to acute coronary syndrome in a western Mexican population.

The macrophage migration inhibitory factor (MIF) is related to the progression of atherosclerosis, which, in turn, is a key factor in the development of acute coronary syndrome (ACS). MIF has a CATT short tandem repeat (STR) at position −794 that might be involved in its expression rate. The aim of this study was to investigate the association between the −794 (CATT)5–8u2009u2009 MIF gene polymorphism and susceptibility to ACS in a western Mexican population. This research included 200 ACS patients classified according to the criteria of the American College of Cardiology (ACC) and 200 healthy subjects (HS). The −794 (CATT)5–8u2009u2009 MIF gene polymorphism was analyzed using a conventional polymerase chain reaction (PCR) technique. The 6 allele was the most frequent in both groups (ACS: 54% and HS: 57%). The most common genotypes in ACS patients and HS were 6/7 and 6/6, respectively, and a significant association was found between the 6/7 genotype and susceptibility to ACS (68% versus 47% in ACS and HS, resp., P = 0.03). We conclude that the 6/7 genotype of the MIF −794 (CATT)5–8 polymorphism is associated with susceptibility to ACS in a western Mexican population.

Aberrant expression of interleukin-10 in rheumatoid arthritis: Relationship with IL10 haplotypes and autoantibodies

HighlightsIn rheumatoid arthritis there is an exacerbated up‐regulation of IL‐10 at the transcriptional level.Increased IL‐10 levels are associated with seropositivity for RF and anti‐CCP antibodies.GCC haplotype was associated with higher IL‐10 serum levels compared with the ACC and ATA haplotypes in RA patients.There was no significant association between IL10 haplotypes and risk of RA in a Mexican population. Abstract Interleukin 10 (IL‐10) is an immunomodulatory cytokine that plays a central role in the pathogenesis of autoimmune diseases. Different studies consistently show increased IL‐10 serum levels in rheumatoid arthritis (RA) and it appears to be caused by genetic variants. Three polymorphisms situated at positions −1082, −819 and −592 of IL10 gene and its major haplotypes have been associated with regulating IL10 promoter activity. In this study, we evaluated whether IL10 haplotypes are associated with mRNA expression and IL‐10 serum levels as well as susceptibility to RA in a Western Mexican population. A total of 240 RA patients and 240 control subjects (CS) were included. Genotyping of IL10 polymorphisms was performed by PCR and PCR‐RFLP, respectively. IL10 mRNA expression was determined by real‐time PCR and IL‐10 serum levels were measured using an ELISA kit. IL10 mRNA expression was 50‐fold higher in RA patients than CS (p < 0.001), while IL‐10 serum levels did not show differences between groups. However, high IL‐10 serum levels were positively related to a higher seropositivity for rheumatoid factor (FR) and anti‐CCP antibodies (p < 0.05). No significant differences between the distribution of haplotype frequencies were observed between both study groups, but GCC haplotype was associated with higher IL‐10 serum levels compared with the ACC and ATA haplotypes in RA patients (p < 0.05). In addition, patients carrying ATA and GCC haplotypes showed higher mRNA expression than ACC (5.4‐fold and 8.8‐fold, respectively) and surprisingly, this trend was reversed in the controls, although it was not significant. In conclusion, our findings suggest that IL10 (GCC, ACC, and ATA) haplotypes may not be a susceptibility marker for RA in a population from Western Mexico. Nevertheless, independently of the presence of these variants, there is an aberrant overexpression of IL10 gene in RA, and it may play an important role in the pathogenesis of RA.

The 14 bp Del/Ins HLA-G Polymorphism Is Related with High Blood Pressure in Acute Coronary Syndrome and Type 2 Diabetes Mellitus

Immunologic and inflammatory processes are involved in the pathogenesis of acute coronary syndrome (ACS) and type 2 diabetes mellitus (DM2). Human leukocyte antigen-G (HLA-G) is a negative regulator of the immune response. This study evaluates the 14 bp Del/Ins HLA-G polymorphism in ACS and DM2. Three hundred and seventy individuals from Western Mexico were recruited and categorized into three groups: ACS (86), DM2 without coronary complications (70), and healthy subjects (214). Genotyping of the 14 bp Del/Ins HLA-G polymorphism was performed by PCR and Native-PAGE. The most common risk factors were hypertension and overweight in ACS and DM2, respectively. The genetic distribution of the 14 bp Del/Ins HLA-G polymorphism showed no significant differences between groups (P ≥ 0.23). Nonetheless, the Ins/Ins genotype was associated with high blood pressure (HBP) in the DM2 group (ORcu2009=u20091.65, P = 0.02). The genetic recessive model showed similar findings (ORcu2009=u20093.03, P = 0.04). No association was found in ACS, with a P of 0.05; nevertheless, the prevalence of Ins/Ins carriers was quite similar to that found in the DM2-HBP group. The 14 bp Del/Ins HLA-G polymorphism was not a susceptibility factor for ACS or DM2; however, the Ins/Ins genotype might have contributed to the development of HBP in the studied groups.