Functional analysis of a polymorphism in the promoter region of the IL-12/23p40 gene

Association of interleukin-12B gene polymorphisms and mRNA expression with preeclampsia

OBJECTIVE

To explore the effects of functional genetic polymorphisms of the interleukin-12B (IL-12B) gene on the susceptibility to preeclampsia in northern Chinese women.

STUDY DESIGN

Maternal peripheral blood from 306 preeclamptic women and 310 control women and the placentas from 52 preeclamptic and 55 control women were collected. Two polymorphisms (rs17860508 and rs3212227) of the IL-12B gene were genotyped by polymerase chain reaction (PCR) with a direct sequencing method. The mRNA expression of IL-12B in the placentas was measured by quantitative real-time PCR (qRT-PCR).

RESULTS

Significant differences were observed between preeclamptic women and the control group in the genotype frequencies of rs17860508 (P = 0.017). Compared with the TTAGAG/TTAGAG genotype of rs17860508, the GC/GC genotype were associated with a higher risk of preeclampsia (adjusted OR: 1.95; 95% CI = 1.18-3.22; P = 0.009), especially the early-onset preeclampsia (adjusted OR: 2.40; 95% CI = 1.23-4.68; P = 0.010). The qRT-PCR results showed that the mRNA levels of IL-12B were significantly higher in the placentas of preeclampsia patients than that in the placentas of controls (P = 0.001). Moreover, the expression of IL-12B mRNA was significantly higher in the placentas of patients carrying the GC/GC genotype than in those carrying the TTAGAG/GC (P = 0.007) and TTAGAG/TTAGAG (P = 0.005) genotypes.

CONCLUSION

The GC/GC genotype of rs17860508 polymorphism may be a risk factor for the early-onset preeclampsia by upregulating the expression of IL-12B in northern Chinese women.

A Functional Polymorphism in the Promoter Region of Interleukin-12B Increases the Risk of Colorectal Cancer

Objective

To investigate whether the polymorphisms of interleukin-12B (IL-12B) were associated with the risk of developing colorectal cancer (CRC). Patients and Methods. Genotypes of rs17860508 and rs3212227 were determined by polymerase chain reaction with a direct sequencing method in 329 CRC patients and 342 matched healthy control subjects. The expression of IL-12B) were associated with the risk of developing colorectal cancer (CRC).

Results

Compared with TTAGAG/TTAGAG genotype of rs17860508, the GC/GC and TTAGAG/GC genotypes may significantly increase the risk of CRC (OR = 1.81, 95% CI = 1.18-2.78; OR = 1.46, 95% CI = 1.01-2.12, respectively). Furthermore, the mRNA levels of IL-12B) were associated with the risk of developing colorectal cancer (CRC). P=0.009) and TTAGAG/TTAGAG (P=0.009) and TTAGAG/TTAGAG (.

Conclusion

These data suggested that the rs17860508 GC/GC genotype might upregulate IL-12B expression at the transcriptional level and thus increase the risk of CRC.IL-12B) were associated with the risk of developing colorectal cancer (CRC).

A functional promoter polymorphism in interleukin 12B gene is associated with an increased risk of ovarian endometriosis

OBJECTIVE

To explore the role of functional genetic variant of IL12B in the pathogenesis of ovarian endometriosis.

STUDY DESIGN

This study included 815 patients with ovarian endometriosis and 788 women in the control group. Two polymorphisms were genotyped by a method of polymerase chain reaction and ligase detection reaction. To assess the biological significance of polymorphisms, we detected the level of IL12p40 protein expression in patients' eutopic endometrial tissues using quantitative real-time polymerase chain reaction (qRT-PCR).

RESULT(S)

Compared with the CTCTAA/CTCTAA genotype, the GC/GC and GC/CTCTAA genotypes of rs17860508 could significantly increase the risk of ovarian endometriosis development (OR = 1.58, 95% CI = 1.19-2.09; OR = 1.37, 95% CI = 1.08-1.74, respectively). Moreover, the IL12B mRNA was expressed at significantly higher levels in the eutopic endometrial tissue of patients with the GC/GC genotype than in patients with the CTCTAA/CTCTAA genotype. However, the rs3212227 polymorphism may not be associated with a risk of ovarian endometriosis.

CONCLUSION(S)

The rs17860508 polymorphism in the IL12B promoter region may influence the risk of developing ovarian endometriosis by altering the endometrial expression of IL12B of in Northern Chinese women.

Increased expression of IL12B mRNA transcribed from the risk haplotype for Crohn's disease is a risk factor for disease relapse in Japanese patients

BACKGROUND

IL12B is a promising candidate for a susceptibility gene in Crohn's disease (CD). The aim of this study was to perform a candidate gene analysis of IL12B in Japanese CD patients, investigate whether the genotype is associated with disease phenotypes, and determine how the risk allele affects susceptibility to CD.

METHODS

Three hundred seventy-five patients with CD, 265 patients with ulcerative colitis, and 463 healthy controls were examined. Ten single-nucleotide polymorphisms (SNPs) around IL12B were genotyped. Case-control and subphenotype (including disease course) analyses were performed. The allelic expression ratio of IL12B messenger RNA (mRNA) was examined by a SNaPshot analysis in lipopolysaccharide-stimulated monocytes.

RESULTS

Four SNPs located upstream of the IL12B gene were significantly associated with CD. A conditional analysis revealed that these associations included two independent signals tagged by IL12B_1 and IL12B_3 (P = 9.42 × 10^-6 and  1.49 × 10^-4 respectively). IL12B_3 was also associated with earlier relapse in CD (P = 0.0144). The allelic expression ratios of IL12B mRNA transcribed from the risk haplotype to the protective haplotype tagged by IL12B_3 in lipopolysaccharide-stimulated monocytes from ten healthy controls heterozygous for IL12B_3 were significantly higher than that of the respective genomic DNA (P = 0.00923). No SNP was associated with ulcerative colitis.

CONCLUSIONS

We confirmed the association of SNPs located upstream of IL12B with CD in Japanese patients. The demonstrated allelic expression imbalance supports the idea that the IL12B risk haplotype confers susceptibility not only to CD onset but to also relapse through increased IL12B mRNA expression.

Genetic Variants in IL-12B and IL-27 in the Polish Patients with Systemic Lupus Erythematosus

To investigate the potential association between IL-12B and IL-27 gene polymorphisms and systemic lupus erythematosus (SLE), we performed a case-control study based on the Polish population. Patients with SLE and healthy individuals were examined for -6415 CTCTAA/GC (rs17860508) and +1188A/C (rs3212227) in IL-12B and -924A/G (rs153109) and 4730T/C (rs181206) in IL-27 gene polymorphisms using the high-resolution melting method, PCR-RFLP method and TaqMan SNP genotyping assay, respectively. An increased frequency of GC/GC genotype as well as GC allele of the IL-12B rs17860508 was found in patients with SLE, as compared with healthy subjects (P < 0.001). We did not find differences in genotype and allele frequencies of the IL-12B rs3212227 and IL-27 rs153109 and rs181206 variants between patients with SLE and controls. IL-27 haplotype rs181206C/rs153109G indicated higher risk for SLE (P = 0.002), whereas haplotype rs181206T/rs153109G indicated reduced risk for SLE (P = 0.005). The IL-12B rs3212227 A/C polymorphism was associated with the mean value of the platelets (PLT), urea and complement C3 level. Furthermore, IL-12B rs17860508 genetic variant showed correlation with PLT, prothrombin time, international normalized ratio and alkaline phosphatase. Our results revealed that IL-12B rs17860508 and IL-27 haplotype CG are genetic risk factors for SLE and that both IL-12B rs17860508 and rs3212227 predict disease phenotype.

Enhanced IL-12p40 production in LPS-stimulated macrophages by inhibiting JNK activation by artemisinin

Artemisinin can be isolated from Artemisia annua L. In addition to its well-known anti-malarial activity, artemisinin has antitumor and anti-microbial effects. In this study, we investigated the effect of artemisinin on the production of IL-12p40, which is important in the generation of T helper 1 responses. Artemisinin significantly induced IL-12p40 production in LPS-stimulated RAW264.7 macrophage cells. To elucidate the signaling molecules regulated by artemisinin in induced IL-12p40 production, the DNA-binding activity of several transcription factors and activation of mitogen-activated protein kinase (MAPK)s were investigated. The band intensities of NF-κB, AP-1, and SP1, and the activation of p38 MAPK and ERK were not changed by artemisinin. However, the induced phosphorylation of JNK was significantly decreased by artemisinin, and inhibition of the JNK signaling pathway further increased IL-12p40 production in LPS-stimulated RAW264.7 macrophage cells. Taken together, these data suggest that artemisinin induces the production of IL-12p40 in LPS-stimulated macrophage cells by inhibiting JNK activity.

No association between IL12B gene polymorphisms and Graves' disease in the Chinese population

BACKGROUND

Graves' disease (GD) is one of the most common autoimmune thyroid disorders and has a striking characteristic of female preponderance.

OBJECTIVE

The main objective of this study was to investigate whether IL12B gene polymorphisms were associated with either GD itself or with gender bias in GD.

METHODS

GD patients (151 males, 97 females) and 211 healthy control subjects without antithyroid autoantibodies or a family history of autoimmune disorders were recruited for this study. The G/C polymorphism (rs6887695) of the IL12B gene was analyzed using the polymerase chain reaction-restriction fragment length polymorphism, and the deletion and insertion polymorphism (rs41292470) in the IL12B promoter was detected after polyacrylamide gel electrophoresis-silver staining method.

RESULTS

There was no significant difference between GD patients and normal subjects, and no differences in frequencies of genotypes or alleles of either polymorphism between male and female GD subjects.

CONCLUSION

We conclude that these IL12B gene polymorphisms were not associated with sex bias in GD and do not confer susceptibility to Graves' disease (GD) in the Chinese population.

Developments in the field of allergy in 2009 through the eyes of Clinical and Experimental Allergy

In 2009 the journal published in the region of 200 papers including reviews, editorials, opinion pieces and original papers that ran the full gamut of allergic disease. It is instructive to take stock of this output to determine patterns of interest and where the cutting edge lies. We have surveyed the field of allergic disease as seen through the pages of Clinical and Experimental Allergy (CEA) highlighting trends, emphasizing notable observations and placing discoveries in the context of other key papers published during the year. The review is divided into similar sections as the journal. In the field of Asthma and Rhinitis CEA has contributed significantly to the debate about asthma phenotypes and expressed opinions about the cause of intrinsic asthma. It has also added its halfpennyworth to the hunt for meaningful biomarkers. In Mechanisms the considerable interest in T cell subsets including Th17 and T regulatory cells continues apace and the discipline of Epidemiology continues to invoke a steady stream of papers on risk factors for asthma with investigators still trying to explain the post-second world war epidemic of allergic disease. Experimental Models continue to make important contributions to our understanding of pathogenesis of allergic disease and in the Clinical Allergy section various angles on immunotherapy are explored. New allergens continue to be described in the allergens section to make those allergen chips even more complicated. A rich and vibrant year helpfully summarized by some of our associate editors.

KIF3A, a cilia structural gene on chromosome 5q31, and its polymorphisms show an association with aspirin hypersensitivity in asthma

INTRODUCTION

The kinesin family number 3A (KIF3A) gene on the human chromosomal 5q31-33 region, which is known as a susceptibility locus for immune diseases including asthma, plays a crucial role in generation of cilia.

RESULTS

A treatment with aspirin in the human bronchial epithelial cells increased the mRNA expression level of KIF3A compared to that of the untreated control (P ≤ 0.01), and nasal polyp epithelia from aspirin-intolerant asthma (AIA) patients also showed a higher expression of KIF3A protein than aspirin-tolerant asthma controls. Further logistic analyses revealed that most polymorphisms of KIF3A were significantly associated with AIA (P = 0.0004-0.02; P(corr) = 0.004-0.04) and the decline of forced expiratory volume at 1 s (FEV(1))% by aspirin provocation (P = 0.004-0.04; P(corr) = 0.03).

DISCUSSION

Our findings suggest that the KIF3A gene and/or its polymorphisms might have a susceptibility effect on AIA, providing a new step toward controlling aspirin intolerance in asthmatics.

A new association between polymorphisms of the SLC6A7 gene in the chromosome 5q31-32 region and asthma

The human chromosomal 5q31-33 region has been implicated as a susceptibility locus for several immune-mediated diseases including asthma in several populations. Recently, the extraneuronal GABAergic system has been implicated as a new link to airway obstruction in asthma. In addition, the SLC6A7 gene, which is positioned at 5q31-32 and encodes the transporter for an excitatory neurotransmitter of L-proline, has never been studied for its association with asthma. In this study, resequencing of all exon, promoter region (2 kb), and exon-intron boundary regions in the SLC6A7 gene found a total of 33 single nucleotide polymorphisms (SNPs) in 24 Korean asthmatic patients. After the initial SNP survey, a total of 17 common SNPs with minor allele frequency (MAF) over 10% were genotyped in 498 asthmatic patients and 303 normal controls. Logistic analyses revealed significant associations between genetic variants of the SLC6A7 gene and asthma (P-value up to 6.0 x 10(-4); P(corr) value up to 0.009). In further regression analyses, minor alleles of intronic +11431T>C, +12213C>T and +12927A>G in linkage disequilibrium block 2 and +20113T>C in 3'UTR significantly increased the bronchodilator response in asthmatics (P-value of recessive model up to 0.008; which are not significant after multiple correction). Therefore, our findings suggest that SLC6A7 could be a susceptible gene for asthma.

Haplotypes of IL12B promoter polymorphisms condition susceptibility to severe malaria and functional changes in cytokine levels in Thai adults

Polymorphic variability in immune response genes, such as IL12B, encoding the IL-12p40 subunit is associated with susceptibility to severe malaria in African populations. Since the role of genetic variation in conditioning severe malaria in Thai adults is largely unexplored, the functional association between IL12B polymorphisms [i.e. IL12Bpro (rs17860508) and IL12B 3' UTR T/G (rs3212227)], severe malaria and cytokine production was examined in patients with Plasmodium falciparum infections (n = 355) recruited from malaria endemic areas along the Thai-Myanmar border in northwest Thailand. Circulating IL-12p40 (p = 0.049) and IFN-gamma (p = 0.051) were elevated in patients with severe malaria, while only IL-12p40 was significantly higher in severe malaria patients with hyperparasitaemia (p = 0.046). Carriage of the IL12Bpro1.1 genotype was associated with enhanced severity of malaria (OR, 2.34; 95% CI, 0.94-5.81; p = 0.066) and hyperparasitaemia (OR, 3.42; 95% CI, 1.17-9.87; p = 0.025) relative to the IL12Bpro2.2 genotype (wild type). Individuals with the IL12Bpro1.1 genotype also had the lowest IL-12p40 (p = 0.002) and the highest IFN-gamma (p = 0.004) levels. Construction of haplotypes revealed that carriage of the IL12Bpro-2/3' UTR-T haplotype was associated with protection against severe malaria (OR, 0.51; 95% CI, 0.29-0.90; p = 0.020) and reduced circulating IFN-gamma (p = 0.06). Thus, genotypic and haplotypic variation at IL12Bpro and IL12B 3' UTR in this population influences susceptibility to severe malaria and functional changes in circulating IL-12p40 and IFN-gamma levels. Results presented here suggest that protection against severe malaria in Thai adults is associated with genotypic variants that condition enhanced IL-12p40 and reduced IFN-gamma levels.

Opposite effects of Trichostatin A on activation of mast cells by different stimulants

Mast cells (MCs) are activated upon stimulation via TLRs or FcepsilonRI, contributing to immune protection and/or leading to allergic diseases. In the present study, the effects of Trichostatin A (TSA) on the activation of MCs were analyzed with bone marrow-derived (BM) MCs. TSA increased the transcription and protein secretion of IL-6 in case of LPS-stimulation, in contrast to the suppressive effect on IgE-mediated activation of BMMCs. Chromatin immunoprecipitation assay showed IgE-mediated signaling-specific suppression of transcription factors recruitment to the IL-6 promoter. TSA-treatment inhibited nuclear translocation of NF-kappaB following IgE-mediated, but not LPS-induced activation in MCs.

The influence of JNK and P38 MAPK inhibition on IL-12P40 and IL-23 production depending on IL12B promoter polymorphism

The interleukin-12p40 gene (IL12B) encodes the p40 polypeptide chain, which, together with p19, composes IL-23. A bi-allelic promoter polymorphism (IL12Bpro) located at -2703 bp of the transcription initiation site has been reported to show associations with IL-12p40 production. To elucidate the dependence of IL-12p40 and IL-23 production on IL12Bpro polymorphism in relation to MAPK signal transduction pathways, we examined the effect of JNK and p38 inhibition on the secretion of these cytokines by stimulated peripheral blood mononuclear cells (PBMC) from healthy donors with 1.1 and 1.2/2.2 IL12Bpro genotypes. Stimulation with LPS and C3bgp resulted in approximately equal IL-12p40 production from PBMC with the 1.1 and 1.2/2.2 genotypes. The inhibition of JNK and p38 before stimulation significantly upregulated IL-12p40 production by PBMC with the 1.1 genotype, but did not influence IL-12p40 production from PBMC with the 1.2/2.2 genotype. Cultures of PBMC with the 1.1 genotype produced significantly more IL-12p40 than PBMC with the 1.2/2.2 genotype after stimulation with PHA. Inhibition of p38 kinase upregulated p40 production only in cultures with the 1.1 genotype. Decreased IL-23 production was observed in C3bgp-stimulated cultures after the inhibition of p38 regardless of the genotype of the tested cells. We concluded that IL-12p40 and IL-23 expression, which is mediated by the p38 and JNK intracellular signaling pathways, is influenced by IL12Bpro polymorphism.