Effects of the multiple sclerosis associated −330 promoter polymorphism in IL2 allelic expression

The prognostic role of gene polymorphisms in patients with indolent non-Hodgkin lymphomas and mantle-cell lymphoma receiving bendamustine and rituximab: results of the 5-year follow-up study

The variability in disease outcome for indolent non-Hodgkin lymphomas (iNHL) and mantle-cell lymphoma (MCL) could be related to single nucleotide polymorphisms (SNPs) in genes that affect immune and inflammatory response. We investigated SNPs that could have a prognostic role for patients receiving bendamustine and rituximab (BR). All samples were genotyped for the IL-2 (rs2069762), IL-10 (rs1800890, rs10494879), VEGFA (rs3025039), IL-8 (rs4073), CFH (rs1065489) and MTHFR (rs1801131) SNPs by allelic discrimination assays using TaqMan SNP Genotyping Assays. We report a long-term follow-up analysis of 79 iNHL and MCL patients that received BR. Overall response rate was 97.5% (CR rate 70.9%). After a median follow-up of 63 months, median PFS and OS were not reached. We report a significant association between SNP in IL-2 (rs2069762) and reduced PFS and OS (p<.0001). We suggest a role for cytokine SNPs in disease outcome, while SNPs seem not related to long-term toxicity or secondary malignancies.

Single nucleotide variants in immune-response genes and the tumor microenvironment composition predict progression of mantle cell lymphoma

Background

There is evidence to consider that the tumor microenvironment (TME) composition associates with antitumor immune response, and may predict the outcome of various non-Hodgkin lymphoma subtypes. However, in the case of mantle cell lymphoma (MCL), a rare and aggressive disease, there is lacking a detailed study of the TME components, as well as an integrative approach among them in patients’ samples. Also, from the genetic point of view, it is known that single nucleotide variants (SNVs) in immune-response genes are among important regulators of immunity. At present, it is uncertain whether SNVs in candidate immune-response genes and the TME composition are able to alter the prognosis in MCL.

Methods

We assessed a detailed TME composition in 88 MCL biopsies using immunohistochemistry, which was automatically analyzed by pixel counting (Aperio system). We also genotyped SNVs located in candidate immune-response genes (IL12A, IL2, IL10, TGFB1, TGFBR1, TGFBR2, IL17A, IL17F) in 95 MCL patients. We tested whether the SNVs could modulate the respective protein expression and TME composition in the tumor compartment. Finally, we proposed survival models in rituximab-treated patients, considering immunohistochemical and SNV models.

Results

High FOXP3/CD3 ratios (p = 0.001), high IL17A levels (p = 0.003) and low IL2 levels (p = 0.03) were individual immunohistochemical predictors of poorer survival. A principal component, comprising high quantities of macrophages and high Ki-67 index, also worsened outcome (p = 0.02). In the SNV model, the CC haplotype of IL10 (p < 0.01), the GG genotype of IL2 rs2069762 (p = 0.02) and the AA+AG genotypes of TGFBR2 rs3087465 (p < 0.01) were independent predictors of outcome. Finally, the GG genotype of TGFB1 rs6957 associated with lower tumor TGFβ levels (p = 0.03) and less CD163+ macrophages (p = 0.01), but did not modulate patients’ survival.

Conclusions

Our results indicate that the TME composition has relevant biological roles in MCL. In this setting, immunohistochemical detection of T-reg cells, IL17A and IL2, coupled with SNV genotyping in IL10, TGFBR2 and IL2, may represent novel prognostic factors in this disease, following future validations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07891-9.

IL-2 modulates Th2 cell responses to glucocorticosteroid: A cause of persistent type 2 inflammation?

Background

Glucocorticosteroids (GCs) are the main treatment for asthma as they reduce type 2 cytokine expression and induce apoptosis. Asthma severity is associated with type 2 inflammation, circulating Th2 cells and higher GC requirements.

Objective

The aim of this study was to assess whether ex vivo production of interleukin 2 (IL‐2), a T‐cell survival factor, associated with clinical features of asthma severity, the proportion of blood Th2 cells and Th2 cell responses to GC.

Methods

Peripheral blood from asthma patients (n = 18) was obtained and the proportion of Th2 cells determined by flow cytometry. Peripheral blood cells were activated with mitogen (24 hours) and supernatant levels of IL‐2 and IL‐13 measured by enzyme‐linked immunosorbent assay. In vitro differentiated Th2 cells were treated with dexamethasone (DEX) and IL‐2 and assessed for apoptosis by flow cytometry (annexin V). Level of messenger RNA (mRNA) for antiapoptotic (BCL‐2) and proapoptotic (BIM) genes, IL‐13, GC receptor (GR) and FKBP5 were determined by quantitative real‐time polymerase chain reaction. GR binding was assessed by chromatin immunoprecipitation.

Results

IL‐2 produced by activated peripheral blood cells correlated negatively with lung function and positively with a daily dose of inhaled GC. When patients were stratified based on IL‐2 level, high IL‐2 producers made more IL‐13 and had a higher proportion of circulating Th2 cells. In vitro, increasing the level of IL‐2 in the culture media was associated with resistance to DEX‐induced apoptosis, with more BCL‐2/less BIM mRNA. Th2 cells cultured in high IL‐2 had more IL‐13, less GR mRNA, showed reduced binding of the GR to FKBP5, a known GC‐induced gene, and required higher concentrations of DEX for cytokine suppression.

Conclusions and Clinical Relevance

IL‐2 downregulates Th2 cell responses to GC, supporting both their survival and pro‐inflammatory capacity. These results suggest that a patient's potential to produce IL‐2 may be a determinant in asthma severity.

A novel predictive approach for GVHD after allogeneic SCT based on clinical variables and cytokine gene polymorphisms

Despite considerable advances in our understanding of the pathophysiology of graft-versus-host disease (GVHD), its prediction remains unresolved and depends mainly on clinical data. The aim of this study is to build a predictive model based on clinical variables and cytokine gene polymorphism for predicting acute GVHD (aGVHD) and chronic GVHD (cGVHD) from the analysis of a large cohort of HLA-identical sibling donor allogeneic stem cell transplant (allo-SCT) patients. A total of 25 SNPs in 12 cytokine genes were evaluated in 509 patients. Data were analyzed using a linear regression model and the least absolute shrinkage and selection operator (LASSO). The statistical model was constructed by randomly selecting 85% of cases (training set), and the predictive ability was confirmed based on the remaining 15% of cases (test set). Models including clinical and genetic variables (CG-M) predicted severe aGVHD significantly better than models including only clinical variables (C-M) or only genetic variables (G-M). For grades 3-4 aGVHD, the correct classification rates (CCR1) were: 100% for CG-M, 88% for G-M, and 50% for C-M. On the other hand, CG-M and G-M predicted extensive cGVHD better than C-M (CCR1: 80% vs. 66.7%, respectively). A risk score was calculated based on LASSO multivariate analyses. It was able to correctly stratify patients who developed grades 3-4 aGVHD (P < .001) and extensive cGVHD (P < .001). The novel predictive models proposed here improve the prediction of severe GVHD after allo-SCT. This approach could facilitate personalized risk-adapted clinical management of patients undergoing allo-SCT.

IL-2 gene polymorphisms affect tacrolimus response in myasthenia gravis

PURPOSE

The IL-2 gene polymorphisms have been reported to be associated with the development of autoimmune disease. However, there are no published studies examining the influence of the IL-2 gene polymorphisms on the response of myasthenia gravis (MG) patients to tacrolimus (Tac). The goal of this study was to investigate the relationship between the polymorphisms of IL-2 and Tac response in MG patients.

METHODS

Ninety-two MG patients treated with Tac were studied, including 57 Tac-effective patients and 35 Tac-ineffective patients. Then, we selected four single-nucleotide polymorphisms (SNPs: rs2069776, rs2069772, rs2069762, rs2069763) in the IL-2 gene. Next, we analyzed the distribution of genotypes, allelic frequencies of SNPs, and haplotype frequencies among polymorphisms in the two groups of patients.

RESULTS

The distribution of the allelic frequency of the rs2069762 variant differed between the Tac-effective and Tac-ineffective patients (P = 0.02). Genotypes G/T and G/G of rs2069762 were differently distributed between the two groups when the wild genotype T/T was assigned as a reference (P < 0.001 for G/T; P = 0.003 for G/G). Patients with the TAGG haplotype tended to be Tac-ineffective (P < 0.001, OR: 0.15, 95% CI: 0.05-0.43).

CONCLUSION

Myasthenia gravis patients with the rs2069762 variant, rs2069762 G/T and G/G genotype, and TAGG haplotype for IL-2 tended to respond poorly to Tac treatment.

A genetic link between CXCR5 and IL2RA gene polymorphisms and susceptibility to multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) is a T-cell-mediated disease of the central nervous system that develops in individuals possessing a complex susceptibility trait. We explored relationship between gene polymorphisms in MS.

METHODS

To identify the associations of CXCR5 and IL2RA gene polymorphisms with susceptibility to MS, we recruited 263 MS patients from the Han nationality and 138 from the Hui nationality as MS group and 284 healthy volunteers from the Han nationality and 156 from the Hui nationality as controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was employed to test gene polymorphisms of IL2RA (rs2104286 and rs12722489). Sequenom MassARRAY system was applied to analyze genotyping of CXCR5 (rs3922).

RESULTS

The genotypes and allele frequency distributions at the loci of IL2RA rs2104286 and rs12722489 showed significant differences between the MS and control groups. The gene polymorphisms at the loci of IL2RA rs2104286 and rs12722489 may increase the onset risk of MS. IL2RA-rs2104286 showed a positive relationship with CXCR5-rs3922. The same relationship was also observed between IL2RA-rs12722489 and CXCR5-rs3922. The genotypes and allele frequencies of loci of rs2104286 and rs12722489 were significantly different in MS clinical subtypes and severity (EDSS score). Additionally, CAC and TGC haplotype at rs3922-rs12722489-rs2104286 may reduce the risk of MS, while CGT and TGT haplotypes increase the risk.

CONCLUSION

The gene polymorphisms at the loci of IL2RA rs2104286 and rs12722489 are closely associated with susceptibility to MS in the Han and Hui nationalities.

Association of -330 interleukin-2 gene polymorphism with oral cancer

Background & objectives

Cytokines play an important role in the development of cancer. Several single-nucleotide polymorphisms (SNPs) of cytokine genes have been reported to be associated with the development and severity of inflammatory diseases and cancer predisposition. This study was undertaken to evaluate a possible association of interleukin 2 (IL-2) (- 330A>C) gene polymorphisms with the susceptibility to oral cancer.

Methods

The SNP in IL-2 (-330A>C) gene was genotyped in 300 oral cancer patients and in similar number of healthy volunteers by polymerase chain reaction (PCR)-restriction fragment length polymorphism and the association of the gene with the disease was evaluated.

Results

IL-2 (-330A>C) gene polymorphism was significantly associated with oral cancer whereas it was neither associated with clinicopathological status nor with cancer pain. The AC heterozygous genotype was significantly associated with oral cancer patients as compared to controls [odds ratio (OR): 3.0; confidence interval (CI): 2.14-4.20; P<0.001]. The C allele frequency was also significantly associated with oral cancer (OR: 1.80; CI: 1.39-2.33; P<0.001). IL-2 (-330A>C) gene polymorphism was also associated with oral cancer in tobacco smokers and chewers.

Interpretation & conclusions

Our results showed that oral cancer patients had significantly higher frequency of AA genotype but significantly lower frequency of AC genotype and C allele compared to controls. The IL-2 AC genotype and C allele of IL-2 (-330A>C) gene polymorphisms could be potential protective factors and might reduce the risk of oral cancer in Indian population.

No association of IL2, IL4, IL6, TNF, and IFNG gene polymorphisms was found with Taenia solium human infection or neurocysticercosis severity in a family-based study

Neurocysticercosis (NC) is caused by the establishment of the metacestode stage of Taenia solium in the human central nervous system. A great heterogeneity in the susceptibility to the infection and to the disease has been reported. While the factors involved in this heterogeneity are not completely understood, clearly different immune-inflammatory profiles have been associated to each condition. This study evaluated the association of cytokine single nucleotide polymorphisms (SNPs) with susceptibility to infection and disease severity in NC patients. Blood samples from 92 NC cases and their parents (trios) were genotyped for SNPs in five cytokines relevant for the immune response: IL4 (-589C/T), IL6 (-174C/G), IFNG (+874T/A), TNF (-238G/A), and IL2 (-330G/T). Specific DNA fragments were amplified by the polymerase chain reaction, using the 5'-nuclease Taqman assay on a 7500 platform, allowing the detection of the polymorphism genotypes. No association between the polymorphisms evaluated neither with susceptibility to infection nor with disease severity was found, although previous studies reported variations in the levels of these cytokines among different NC clinical pictures. These results, nevertheless, add new elements to our understanding of the complex pathogenic mechanisms involved in susceptibility to infection by T. solium cysticerci and the severity of the ensuing disease.

Association of Interleukin-2-330T/G and Interleukin-10-1082A/G Genetic Polymorphisms with B-Cell Non-Hodgkin Lymphoma in a Cohort of Egyptians

Objective:

Polymorphisms in the interleukin (IL)-2 and IL-10 genes are known to be associated with susceptibility to different immune-dysregulated disorders and cancers such as non-Hodgkin lymphoma (NHL). To explore the possible association between IL-2-330T/G and IL-10-1082A/G single-nucleotide polymorphisms and the susceptibility to B-cell NHL (B-NHL) in Egyptians, we conducted a case-control study.

Materials and Methods:

Genotyping of the studied genetic variations was done for 100 B-NHL patients as well as 100 age- and sex-matched healthy controls.

Results:

The IL-2 variant allele occurred at a significantly higher rate in patients than controls and was associated with susceptibility to B-NHL [odds ratio (OR): 1.91, 95% confidence interval (CI): 1.28-2.85]. It was also associated with advanced performance status score. IL-2 polymorphism conferred an almost threefold increased risk of diffuse large B-cell lymphoma (OR: 2.64, 95% CI: 1.35-5.15) and a fourfold increased risk of indolent subtypes (OR: 4.34, 95% CI: 1.20-15.7). The distribution of IL-10-1082A/G genotypes in our patients was close to that of the controls. Co-inheritance of the variant genotypes of IL-2 and the common genotype of IL-10 conferred an almost sixfold increased risk (OR: 5.75, 95% CI: 1.39-23.72), while co-inheritance of the variant genotypes of IL-2 and IL-10 conferred fivefold increased risk of B-NHL (OR: 5.43, 95% CI: 1.44-20.45). The variant genotypes of IL-2-330T/G and IL-10-1082A/G had no effect on the disease-free survival of B-NHL patients.

Conclusion:

The present study highlights the possible involvement of the IL-2-330T/G genetic polymorphism in the susceptibility to B-NHL in Egypt, especially indolent subtypes. Moreover, IL-10-1082A/G is not a molecular susceptibility marker for B-NHL in Egyptians.

New challenges and promises in solid organ transplantation pharmacogenetics: the genetic variability of proteins involved in the pharmacodynamics of immunosuppressive drugs

Interindividual variability in immunosuppressive drug responses might be partly explained by genetic variants in proteins involved in the immune response or associated with IS pharmacodynamics. On a general basis, the pharmacogenetics of drug target proteins is less known and understood than that of proteins involved in drug disposition pathways. The aim of this review is to facilitate research related to the pharmacodynamics of the main immunosuppressive drugs used in solid organ transplantation. We elaborated a quality of evidence grading system based on a literature review and identified 'highly recommended', 'recommended' or 'potential' candidates for further research. It is likely that a number of additional rare variants might further explain drug response phenotypes in transplantation, and particularly the most severe ones. The advent of next-generation sequencing will help to identify those variants.

Association between cytokine gene polymorphisms and tuberculosis in a Chinese population in Shanghai: a case-control study

BACKGROUND

Polymorphisms in cytokine genes are known to influence cytokine levels, which may influence susceptibility to tuberculosis (TB) infection and disease. Differences in cytokine expression probably determine whether TB progresses, resolves, or becomes latent. In particular, the balance between the Th1 and Th2 cytokine responses influences the expression of disease in individuals with pulmonary TB (PTB). We performed a case-control study of 120 patients diagnosed with PTB, 240 with latent TB infection (LTBI), and 480 healthy controls (HC), to explore the association between polymorphisms in cytokine genes and a predisposition to Mycobacterium tuberculosis infection and TB disease.

RESULTS

A single-gene analysis showed a dominant association between the AA genotype or A allele at nucleotide -874 of the interferon γ (IFN-γ) gene and LTBI. The A allele at nucleotide -1082 of the interleukin 10 (IL-10) gene was significantly more common in PTB patients than in LTBI subjects. Moreover, the polymorphisms at IFN-γ -874 and IL10 - 1082 were associated with protein levels of IFN-γ and IL-10, respectively, in the PTB group. The genotype frequencies of other polymorphisms did not differ between the PTB patients, LTBI and HC subjects. Furthermore, combinations of polymorphisms with IFN-γ -874 were associated with LTBI, whereas combinations with IL10 - 1082 were more likely associated with PTB.

CONCLUSIONS

There are positive associations between the IFN-γ -874 polymorphism and TB and between the IL10 - 1082 polymorphism and LTBI. Our data provide genetic evidence of the multiple disease hypothesis that many cytokine genes are involved in TB susceptibility.

4q27 as a psoriasis susceptibility locus in the Northeastern Chinese Han population

Psoriasis is an autoimmune inflammatory skin disease with genetic components. Chromosome 4q27 is related to many autoimmune diseases, however, the relationship between psoriasis and 4q27 has not been fully established yet. The objective of this study is to investigate the association between chromosome 4q27 and psoriasis in the Northeastern Chinese Han population. Four common single nucleotide polymorphisms (rs2069762, rs4833837, rs6840978, and rs7684187) from chromosome 4q27 were genotyped in 400 psoriasis cases and 398 controls from the Northeastern Chinese Han population using the Multiplex SNaPSHOT method. Single nucleotide polymorphism and haplotype frequencies were analyzed using spss 13.0. Our data indicated that rs2069762 GG, TG genotypes [GG: odds ratio (OR) = 2.6875, 95% confidence interval (CI) = 1.5948-4.5290, P < 0.0001; TG: OR = 1.6159, 95% CI = 1.2044-2.1681, P = 0.0013], and H3 haplotype (OR = 1.717, 95% CI = 1.050-2.808, P = 0.030) increased the risk of psoriasis. Furthermore, rs4833837 GG, GA genotypes (GG: OR = 0.2071, 95% CI = 0.0685-0.6266, P = 0.0022; GA: OR = 0.4711, 95% CI = 0.3289-0.6746, P < 0.0001), and H5 haplotype (OR = 0.482, 95% CI = 0.238-0.978, P = 0.039) were identified as protective factors for psoriasis. 4q27 polymorphisms are associated with psoriasis in the Northeastern Chinese Han population.

Interleukin-2 and subunit alpha of its soluble receptor in autoimmune Addison's disease--an association study and expression analysis

Autoimmune Addison's disease (AAD) results from T cell-mediated destruction of the adrenal cortex, commonly accompanied by autoantibodies to 21-hydroxylase (21OH). In order to gain insight into the obscure aetiology of this disease, we investigated the roles of the IL2 and IL2RA genes, encoding interleukin-2 and subunit alpha of its receptor (IL2Ra), respectively. The association of AAD with IL2 and IL2RA polymorphisms (rs6822844, rs2069762, rs3136534, rs11594656, rs3118470 and rs2104286) was tested in 223 patients and 672 healthy controls. Functional studies consisted of gene expression analysis in cultured PBMCs exposed to 21OH and evaluation of serum interleukin by ELISA assays. The frequency of the minor C allele of rs3136534 was significantly decreased in AAD subjects compared to controls (OR 0.71; 95%CI 0.561-0.887; p = 0.003). Only AAD cells responded to 21OH with an elevated IL2 and IL2RA mRNA synthesis (p = 0.004 and p = 0.009 versus controls, respectively), paralleled by increased supernatant levels of both cytokines (p = 0.031 and p = 0.001 versus controls). IL2 mRNA level in 21OH-stimulated AAD PBMCs correlated negatively with age (p = 0.036) and positively with serum antibodies to 21OH (p = 0.006). Carriers of the rs2104286 AA genotype demonstrated higher IL2RA mRNA (p = 0.022) and soluble IL2Ra secretion (p = 0.029) upon 21OH stimulation. Serum interleukin-2 in AAD subjects was significantly higher compared to controls (4.61 ± 4.3 versus 1.71 ± 3.2 pg/mL, p < 0.001), whereas sIL2Ra levels remained similar in both groups (p = 0.885). In conclusion, the study reveals an association between AAD and IL2 locus. It confirms specific 21OH-directed reactivity of the peripheral AAD lymphocytes, which display increased synthesis of interleukin-2 and sIL2Ra.

Unexpected phenotype of mice lacking Shcbp1, a protein induced during T cell proliferation

T cell development and activation are highly regulated processes, and their proper execution is important for a competent immune system. Shc SH2-domain binding protein-1 (Shcbp1) is an evolutionarily conserved protein that binds to the adaptor protein ShcA. Studies in Drosophila and in cell lines have strongly linked Shcbp1 to cell proliferation, embryonic development, growth factor signaling, and tumorigenesis. Here we show that Shcbp1 expression is strikingly upregulated during the β-selection checkpoint in thymocytes, and that its expression tightly correlates with proliferative stages of T cell development. To evaluate the role for Shcbp1 during thymic selection and T cell function in vivo, we generated mice with global and conditional deletion of Shcbp1. Surprisingly, the loss of Shcbp1 expression did not have an obvious effect during T cell development. However, in a mouse model of experimental autoimmune encephalomyelitis (EAE), which depends on CD4⁺ T cell function and mimics multiple features of the human disease multiple sclerosis, Shcbp1 deficient mice had reduced disease severity and improved survival, and this effect was T cell intrinsic. These data suggest that despite the striking upregulation of Shcbp1 during T cell proliferation, loss of Shcbp1 does not directly affect T cell development, but regulates CD4⁺ T cell effector function in vivo.

The association of -330 interleukin-2 gene polymorphism with its plasma concentration in Iranian multiple sclerosis patients

Multiple sclerosis (MS) is a chronic neuroinflammatory demyelinating disease of the central nervous system. The cytokine genes are involved in autoimmune diseases such as MS. In this study, we report the influence of -330 interleukin-2 (IL2) gene polymorphism on its plasma levels in a group of Iranian MS patients. In this study 100 MS patients and 100 ethnically, age, and sex matched healthy controls were selected from Medical Genetics Department of Sarem Women Hospital. Blood samples of all individuals were collected in EDTA tubes. The restriction fragment length polymorphism PCR (RFLP) method was applied to determine various alleles and genotypes in these individuals. Plasma concentration of IL2 was measured in all the samples using human IL2 kit. The frequency of -330 T/T IL2 genotype was higher in MS patients compared to normal individuals. Accordingly, the plasma levels of IL2 were significantly higher (P < 0.0001) in patients when compared to the control group. In conclusion, in case of MS patients the -330 T/T IL2 genotype is associated with higher plasma levels of IL2.

Polymorphic variant at the IL2 region is associated with type 1 diabetes and may affect serum levels of interleukin-2

Polymorphic variants at the interleukin-2 (IL2) locus affect the risk of several autoimmune disorders. Our aim was to evaluate the association of the four IL2 polymorphisms (rs6822844, rs6534349, rs2069762 and rs3136534) with type 1 diabetes (T1D) in the Polish population, and to correlate them with the serum interleukin-2 levels. 543 unrelated T1D patients and 706 healthy control subjects were enrolled. The minor T allele at rs6822844 was significantly less frequent in T1D compared to controls (p = 0.002; OR 0.71; 95 % CI 0.571–0.880). Likewise, the frequency of the TT genotype was decreased among the affected individuals (p = 0.007). In healthy subjects, stratification according to the rs6822844 genotype revealed significant differences in circulating interleukin-2 (p = 0.037) with the highest levels in TT protective genotypes. Three other IL2 polymorphisms did not display significant differences in allele and genotype distribution. In conclusion, the rs6822844 variant is associated with T1D and may play a functional role, or reflect the influence of another causative genetic variant in linkage disequilibrium.

Interleukin-2 gene polymorphisms and prognosis of breast cancer

Breast cancer is the most common malignancy in women. Interleukin-2 (IL-2) plays a key role in the proliferation of T cells and natural killer cells. It has been reported that polymorphisms in the IL-2 gene are associated with various cancers. The aim of this study was to examine the effect of polymorphisms in the IL-2 gene on the development of breast cancer in the Chinese population. IL-2-330T/G and +114T/G polymorphisms were assessed in 638 breast cancer cases and 682 age-matched healthy controls. Data were analyzed using the chi-square test. Results showed that individuals with -330TG genotype and -330GG genotype had significantly increased susceptibility to breast cancer (Odds ratio [OR]=1.42, 95% confidence interval [CI]: 1.10-1.79, p=0.0021 and OR=2.26, 95%CI: 1.53-3.30, p<0.0001). The +114T/G polymorphism did not show any correlation with breast cancer. In addition, when analyzing the survival time of breast cancer patients with IL-2-330T/G polymorphism, cases with a -330G allele had significantly shorter survival time compared with wild-type patients (p=0.002). These results suggested that polymorphism in the IL-2 gene was associated with increased susceptibility to breast cancer and could be used as a prognostic marker for this malignancy.

Interleukin-2 gene polymorphism in Turkish patients with Behçet's disease and its association with ocular involvement

Behçet's disease (BD) is a chronic immune-mediated systemic disease, characterized by oral and genital lesions and ocular inflammation. Several cytokine genes may play crucial roles in host susceptibility to BD, because the cytokine production capacity varies among individuals and depends on the cytokine gene polymorphisms. The association of the interleukin (IL)-2 gene polymorphisms with the susceptibility to BD was investigated in this study. DNA samples were obtained from a Turkish population of 97 patients with BD and 76 healthy control subjects. Polymorphisms of IL-2 gene at position -330 and +166 were determined using the polymerase chain reaction with sequence-specific primers. In the patients with BD, there was a significantly increased frequency of IL-2 -330 GT genotype. Interestingly, we demonstrated that the frequencies of IL-2 -330 GT and IL-2 + 166 GG genotypes were increased in BD patients with ocular involvement, whilst IL-2 -330 TT genotype was significantly decreased. Also, analysis of allele frequency demonstrated that the presence of G allele at position +166 of IL-2 seems to be a risk factor for ocular involvement. These results reveal that IL-2 -330 GT genotype may be a susceptibility factor for BD, whereas IL-2 -330 TT genotype seems to display a protective association with BD. Additionally, IL-2 gene polymorphisms might be associated with ocular involvement in BD.

Interleukin 2 gene polymorphisms are associated with non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy worldwide. Interleukin-2 (IL-2) plays a key role in the proliferation of T cells and natural killer cells. It has been reported that polymorphisms in the IL-2 gene are associated with various cancers. The aim of this study was to examine the effect of polymorphisms in the IL-2 gene on the development of NHL in the Chinese population. IL-2-330T/G and +114T/G polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism in 438 NHL cases and 482 age-matched healthy controls. Data were analyzed using the Chi-square test. Results showed that individuals with -330TG genotype or -330GG genotype had significantly increased susceptibility to NHL (Odds ratio [OR] = 1.40, 95% confidence interval [CI]: 1.05-1.85, p = 0.020 and OR = 2.04, 95%CI: 1.28-3.24, p = 0.002). Meanwhile, the +114T/G polymorphism did not show any correlation with NHL. When analyzing the haplotypes of these two polymorphisms, the prevalence of -330G/+114T haplotype was significantly higher in NHL cases than in controls (OR = 1.45, 95%CI: 1.12-1.88, p = 0.005). These data indicate that IL-2 gene polymorphisms may be new risk factors for NHL.

Compensatory T-cell regulation in unaffected relatives of SLE patients, and opposite IL-2/CD25-mediated effects suggested by coreferentiality modeling

In human systemic lupus erythematosus (SLE), diverse autoantibodies accumulate over years before disease manifestation. Unaffected relatives of SLE patients frequently share a sustained production of autoantibodies with indiscriminable specificity, usually without ever acquiring the disease. We studied relations of IgG autoantibody profiles and peripheral blood activated regulatory T-cells (aTregs), represented by CD4⁺CD25^bright T-cells that were regularly 70–90% Foxp3⁺. We found consistent positive correlations of broad-range as well as specific SLE-associated IgG with aTreg frequencies within unaffected relatives, but not patients or unrelated controls. Our interpretation: unaffected relatives with shared genetic factors compensated pathogenic effects by aTregs engaged in parallel with the individual autoantibody production. To study this further, we applied a novel analytic approach named coreferentiality that tests the indirect relatedness of parameters in respect to multivariate phenotype data. Results show that independently of their direct correlation, aTreg frequencies and specific SLE-associated IgG were likely functionally related in unaffected relatives: they significantly parallelled each other in their relations to broad-range immunoblot autoantibody profiles. In unaffected relatives, we also found coreferential effects of genetic variation in the loci encoding IL-2 and CD25. A model of CD25 functional genetic effects constructed by coreferentiality maximization suggests that IL-2-CD25 interaction, likely stimulating aTregs in unaffected relatives, had an opposed effect in SLE patients, presumably triggering primarily T-effector cells in this group. Coreferentiality modeling as we do it here could also be useful in other contexts, particularly to explore combined functional genetic effects.

Interleukin-2 -330T>G genetic polymorphism associates with prognosis following surgery for thoracic esophageal squamous cell cancer

BACKGROUND

Key molecules in the T helper (Th)1 and Th2 pathways underlie differential responses to the progression and surgical treatment of cancer. We investigated the relationship between Th1/Th2 cytokine polymorphism and prognosis in patients with thoracic esophageal squamous cell cancer.

MATERIALS AND METHODS

The study participants were 159 Japanese patients treated for thoracic esophageal squamous cell cancer with curative esophagectomy at Akita University Hospital. We determined the associations between prognosis following esophagectomy and genetic polymorphisms in Th1 cytokines (interleukin [IL]-2, Interferon-γ, IL-12β), and Th2 cytokines (IL-4, IL-10).

RESULTS

IL-2 -330T>G genetic polymorphism was significantly associated with prognosis after esophagectomy. Univariate and multivariate analyses using a Cox proportional hazards model revealed that patients carrying the IL-2 -330G/G genotype had a significantly poorer prognosis than those carrying the T/G or T/T genotype. However, IL-2 -330T>G polymorphism was not associated with preoperative serum IL-2 levels. Moreover, interferon-γ, IL-12β, IL-4, and IL-10 genetic polymorphisms were not associated with prognosis after esophagectomy for thoracic esophageal squamous cell cancer.

CONCLUSIONS

It is suggested that IL-2 -330T>G genetic polymorphism may be a predictive factor for prognosis in patients receiving esophagectomy for thoracic esophageal squamous cell cancer.

Gene-gene interaction in regulatory T-cell function in atopy and asthma development in childhood

BACKGROUND

Regulatory T-cell dysfunction is associated with development of the complex genetic conditions atopy and asthma. Therefore, we hypothesized that single nucleotide polymorphisms in genes involved in the development and function of regulatory T cells are associated with atopy and asthma development.

OBJECTIVE

To evaluate main effects and gene-gene interactions of haplotype tagging single nucleotide polymorphisms of genes involved in regulatory T-cell function-IL6, IL6R, IL10, heme-oxygenase 1 (HMOX1), IL2, Toll-like receptor 2 (TLR2), TGFB1, TGF-beta receptor (TGFBR)-1, TGFBR2, IL2RA, and forkhead box protein 3 (FOXP3)-in relation to atopy and asthma.

METHODS

Single-locus and multilocus associations with total IgE (3rd vs 1st tertile); specific IgE to egg, milk, and indoor allergens; and asthma were evaluated by chi(2) tests and the multifactor dimensionality-reduction method in 3 birth cohorts (Allergenic study).

RESULTS

Multiple statistically significant multilocus associations existed. IL2RA rs4749926 and TLR2 rs4696480 associated with IgE in both age groups tested (1-2 and 6-8 years). TGFBR2 polymorphisms associated with total and specific IgE in both age groups and with asthma. TGFBR2 rs9831477 associated with specific IgE for milk at age 1 to 2 years and indoor allergens at age 6 to 8 years. For milk-specific IgE, interaction between TGFBR2 and FOXP3 polymorphisms was confirmed by logistic regression and consistent in 2 birth cohorts and when stratified for sex, supplying internal replications.

CONCLUSION

Genes involved in the development and function of regulatory T cells, specifically IL2RA, TLR2, TGFBR2, and FOXP3, associate with atopy and asthma by gene-gene interaction. Modeling of multiple gene-gene interactions is important to unravel further the genetic susceptibility to atopy and asthma.

IL-2 and IL-10 gene polymorphisms are associated with respiratory tract infection and may modulate the effect of vitamin E on lower respiratory tract infections in elderly nursing home residents

BACKGROUND

Vitamin E supplementation may be a potential strategy to prevent respiratory tract infections (RIs) in the elderly. The efficacy of vitamin E supplementation may depend on individual factors including specific single nucleotide polymorphisms (SNPs) at immunoregulatory genes.

OBJECTIVE

We examined whether the effect of vitamin E on RIs in the elderly was dependent on genetic backgrounds as indicated by SNPs at cytokine genes.

DESIGN

We used data and DNA from a previous vitamin E intervention study (200 IU vitamin E or a placebo daily for 1 y) in elderly nursing home residents to examine vitamin E-gene interactions for incidence of RI. We determined the genotypes of common SNPs at IL-1beta, IL-2, IL-6, IL-10, TNF-alpha, and IFN-gamma in 500 participants. We used negative binomial regression to analyze the association between genotype and incidence of infection.

RESULTS

The effect of vitamin E on lower RI depended on sex and the SNP at IL-10 -819G-->A (P = 0.03 for interaction for lower RI). Furthermore, we observed that subjects with the least prevalent genotypes at IL-2 -330A-->C (P = 0.02 for upper RI), IL-10 -819G-->A (P = 0.08 for upper RI), and IL-10 -1082C-->T (P < 0.001 for lower RI in men) had a lower incidence of RI independent of vitamin E supplementation.

CONCLUSIONS

Studies that evaluate the effect of vitamin E on RIs should consider both genetic factors and sex because our results suggest that both may have a significant bearing on the efficacy of vitamin E. Furthermore, common SNPs at cytokine genes may contribute to the individual risk of RIs in the elderly. This trial was registered at clinicaltrials.gov as NCT00758914.

Inflammatory genetic markers of prostate cancer risk

Prostate cancer is the most common cancer in Western society males, with incidence rates predicted to rise with global aging. Etiology of prostate cancer is however poorly understood, while current diagnostic tools can be invasive (digital rectal exam or biopsy) and/or lack specificity for the disease (prostate-specific antigen (PSA) testing). Substantial histological, epidemiological and molecular genetic evidence indicates that inflammation is important in prostate cancer pathogenesis. In this review, we summarize the current status of inflammatory genetic markers influencing susceptibility to prostate cancer. The focus will be on inflammatory cytokines regulating T-helper cell and chemokine homeostasis, together with the Toll-like receptors as key players in the host innate immune system. Although association studies indicating a genetic basis for prostate cancer are presently limited mainly due to lack of replication, larger and more ethnically and clinically defined study populations may help elucidate the true contribution of inflammatory gene variants to prostate cancer risk.

Etiology of type 1 diabetes

Recent genetic mapping and gene-phenotype studies have revealed the genetic architecture of type 1 diabetes. At least ten genes so far can be singled out as strong causal candidates. The known functions of these genes indicate the primary etiological pathways of this disease, including HLA class II and I molecules binding to preproinsulin peptides and T cell receptors, T and B cell activation, innate pathogen-viral responses, chemokine and cytokine signaling, and T regulatory and antigen-presenting cell functions. This review considers research in the field of type 1 diabetes toward identifying disease mechanisms using genetic approaches. The expression and functions of these pathways, and, therefore, disease susceptibility, will be influenced by epigenetic and environmental factors. Certain inherited immune phenotypes will be early precursors of type 1 diabetes and could be useful in future clinical trials.

Influence of interleukin polymorphisms on development of gastric cancer and peptic ulcer

Pro-inflammatory cytokines are produced in the gastric mucosa by inflammatory cells activated by chronic Helicobacter pylori (H. pylori) infection. Polymorphisms of these cytokine genes are associated with individual differences in gastric mucosal cytokine mRNA level, which result in differences in gastric mucosal inflammation, acid inhibition and gastroduodenal disease risk in response to H. pylori infection. Although polymorphisms of interleukin (IL)-1B, IL-1RN and TNF-A have been reported to relate well with gastric cancer and peptic ulcer risk, those of IL-2, IL-4, IL-6 and IL-8 genes are unclear. In combined analyses using data from previous studies, we found that the risk of gastric non-cardia cancer development was significantly associated with IL-4-168 C allele (OR: 0.81, 95% CI: 0.69-1.00) and IL-4-590 T allele carrier status (0.61, 0.53-0.73), and IL-6-174 G/G genotype (2.02, 1.31-3.10). In peptic ulcer development, IL-2-330 G and IL-4-590 T allele carriers had a significantly decreased risk (0.37, 0.27-0.50 and 0.58, 0.34-0.99, respectively). Moreover, IL-2, IL-4, IL-6 and IL-8 gene genotypes prevalence differs among populations. The inflammatory cytokine gene polymorphisms (e.g. IL-4-590 and IL-6-572 for gastric cancer, and IL-4-590, IL-6-572 and IL-8-251 for peptic ulcer) have a more potent influence on development of gastroduodenal diseases in Western than East Asian populations. These cytokine gene polymorphisms, as well as those of IL-1B, IL-1RN and TNF-A, may be used to identify groups at higher risk of gastric cancer and peptic ulcer, and those suitable for their prevention by H. pylori eradication therapy in Western populations.

The 4q27 locus and prostate cancer risk

Background

Chronic inflammation is considered to be implicated in the development of prostate cancer. In this study we are the first to investigate a potential association between variants in an autoimmune related region on chromosome 4q27 and prostate cancer risk. This region harbors two cytokine genes IL-2 and the recently described IL-21.

Methods

We genotyped six variants previously associated with autoimmune disease (namely rs13151961, rs13119723, rs17388568, rs3136534, rs6822844 and rs6840978) and one functional IL-2 promoter variant (rs2069762) for possible association with prostate cancer risk using the Australian Risk Factors for Prostate Cancer case-control Study.

Results

Overall, our results do not support an association between the seven variants at position 4q27 and prostate cancer risk. Per allele odds ratios (ORs) were not significantly different from 1 (all P-values = 0.06). However, we found suggestive evidence for a significant association between the presence of the rs13119723 variant (located in a protein of unknown function) and men with a family history of prostate cancer in first-degree relatives (P-value for interaction 0.02). The per allele OR associated with this variant was significantly higher than 1 (2.37; 95% C.I. = 1.01-5.57).

Conclusions

We suggest that genetic variation within the chromosome 4q27 locus might be associated with prostate cancer susceptibility in men with a family history of the disease. Furthermore, our study alludes to a potential role of unknown protein KIAA1109 in conferring this risk.

Interferon gamma gene +874A/T polymorphism and intracellular interferon gamma expression in pulmonary tuberculosis

We investigated whether IFN-gamma gene +874(A/T) polymorphism influences intracellular interferon gamma expression in T-cell subsets of normal healthy subjects (NHS) and pulmonary tuberculosis patients (PTB). Peripheral blood mononuclear cells were stimulated with live Mycobacterium tuberculosis (MTB) and the intracellular IFN-gamma expression was studied using flow cytometry. Genotyping of IFN-gamma gene +874(A/T) was done using allele specific polymerase chain reaction. Significantly increased IFN-gamma expressing CD3+CD4+ and CD3+CD8+ T cells were observed in NHS with AA genotype compared to TT genotype in unstimulated (p=0.0308 and p=0.0157) and MTB stimulated (p=0.0494 and p=0.0287) cultures and this difference was not observed in PTB patients. The present study suggests that the variant genotypes of IFN-gamma (+874) may be associated with altered expression of IFN-gamma at the intracellular level and play an immunoregulatory role at the site of M. tuberculosis infection.

Variation in cytokine genes can contribute to severity of acetabular osteolysis and risk for revision in patients with ABG 1 total hip arthroplasty: a genetic association study

BACKGROUND

The differences in total hip arthroplasty (THA) survivorship may be influenced by individual susceptibility to periprosthetic osteolysis. This may be driven by functional polymorphisms in the genes for cytokines and cytokine receptors involved in the development of osteolysis in THA, thereby having an effect on the individual's phenotype.

METHODS

We performed a study on 22 single-nucleotide polymorphisms (SNPs) for 11 cytokines and two cytokine receptor candidate genes for association with severity of acetabular osteolysis and risk to failure in THA. Samples from 205 unrelated Caucasian patients with cementless type THA (ABG 1) were investigated. Distribution of investigated SNP variants between the groups of mild and severe acetabular osteolysis was determined by univariate and multivariate analysis. Time-dependent output variables were analyzed by the Cox hazards model.

RESULTS

Univariate analysis showed: 1) TNF-238*A allele was associated with severe osteolysis (odds ratio, OR = 6.59, p = 0.005, population attributable risk, PAR 5.2%); 2) carriers of the IL6-174*G allele were 2.5 times more prone to develop severe osteolysis than non-carriers (OR = 2.51, p = 0.007, PAR = 31.5%); 3) the carriage of IL2-330*G allele was associated with protection from severe osteolysis (OR = 0.55, p = 0.043). Based on logistic regression, the alleles TNF-238*A and IL6-174*G were independent predictors for the development of severe acetabular osteolysis. Carriers of TNF-238*A had increased cumulative hazard of THA failure according to Cox model (p = 0.024). In contrast, IL2-330*G allele predicted lower cumulative hazard of THA failure (p = 0.019).

CONCLUSION

Genetic variants of proinflammatory cytokines TNF-alpha and IL-6 confer susceptibility to severe OL. In this way, presence of the minor TNF allele could increase the cumulative risk of THA failure. Conversely, SNP in the IL2 gene may protect carriers from the above THA complications.

IL2-330G polymorphic allele is associated with decreased risk of Helicobacter pylori infection in adulthood

We evaluated whether polymorphisms in genes coding molecules linked to the innate and adaptive immune response are associated with susceptibility to Helicobacter pylori infection. IL1B-511C-->T, IL1B-31T-->C, IL1RN allele 2, IL2-330T-->G, TNFA-307G-->A, TLR2Arg677Trp, TLR2Arg753Gln, TLR4Asp299Gly, and TLR5(392STOP) polymorphisms were determined in 541 blood donors. IL2-330T-->G allele carriers had a decreased H. pylori infection risk (OR=0.63, 95% CI=0.43-0.93) after adjustment for demographic and environmental factors. Hence, we investigated whether the polymorphism is functional by evaluating IL-2 serum concentration in 150 blood donors and 100 children. IL-2 pro-inflammatory and anti-inflammatory properties were indirectly investigated by determining serum IFN-gamma and IL-10/TGF-beta levels. The polymorphism was associated with increased mean IL-2 levels in H. pylori-positive adults (2.65 pg/mL vs. 7.78 pg/mL) and children (4.19 pg/mL vs. 8.03 pg/mL). Increased IL-2 was associated with pro-inflammatory activity in adults (IFN-gamma=18.61 pg/mL vs. 25.71 pg/mL), and with anti-inflammatory activity in children (IL-10=6.99 vs. 14.17 pg/mL, TGF-beta=45.88 vs. 93.44 pg/mL) (p<10(-3) for all). In conclusion, in the context of H. pylori infection, IL2-330 T-->G polymorphism is functional and is associated with decreased risk of infection in adults.

Promoter polymorphisms of IL2, IL4, and risk of gastric cancer in a high-risk Chinese population

Interleukin 2 (IL2) is a typical Th1 cytokine, and interleukin 4 (IL4) is an inducible Th2 cytokine. These cytokines are critical mediators of the Th1/Th2 balance and apoptosis potential and involved in the process of inflammation-mediated carcinogenesis in human organs, including the gastrointestinal tract. Therefore, we tested the hypothesis that functional variants in IL2 and IL4 were associated with risk of gastric cancer by genotyping two promoter polymorphisms in IL2 G-330T (rs2069762) and IL4 T-168C (rs2070874) in a case-control study of 1045 patients with incident gastric cancer and 1100 cancer-free controls in a high-risk Han Chinese population. We found that, compared with the IL4 -168TT genotype, heterozygous -168TC and combined -168TC/CC genotypes were associated with a significantly decreased gastric cancer risk [adjusted odds ratio (OR) = 0.81, 95% confidence interval (CI) = 0.67-0.98 for -168TC; OR = 0.83, 95% CI = 0.69-1.00 for -168TC/CC, respectively]. Furthermore, this significant protective effect was more evident for gastric cardia cancer patients (adjusted OR = 0.73, 95% CI = 0.56-0.95 for -168TC/CC vs. -168TT). For IL2 G-330T, subjects carrying GT/TT genotypes also had a significantly reduced risk of gastric cardia cancer (adjusted OR = 0.68, 95% CI = 0.46-0.99), compared with those carrying the GG genotype. Our results indicate that IL4 T-168C and IL2 G-330T promoter polymorphisms may contribute to the etiology of gastric cardia cancer in Chinese populations.

Multiple sclerosis association study with the TENR-IL2-IL21 region in a Spanish population

Polymorphisms from the TENR-IL2-IL21 block in the 4q27 chromosome were recently associated with type 1 diabetes, celiac disease, rheumatoid arthritis and psoriasis. We undertook this study to investigate the potential role of polymorphisms rs3136534, rs6822844 and rs2069762 (-330 T/G IL2) in multiple sclerosis (MS) (805 patients of Spanish Caucasian origin and 952 health controls). We did not find evidence for association with any single nucleotide polymorphisms (SNPs) tested. Allele and genotype frequencies of the SNPs, which were studied, were similar in DRB1*15-positive or DRB1*15-negative patients. After stratification of MS patients by clinical course, a weak association was observed with rs2069762 G allele and haplotype bearing this allele with secondary progressive MS, although these cases represent 22% of the MS cases. Our results did not show major influence of TENR-IL2-IL21 locus on susceptibility or disease progression in MS. However, we could not exclude completely the effect in MS for this region. Additional studies, using much larger sample sizes and analysis of additional polymorphisms in the gene and its flanking region, will be required to ascertain their contributions to MS susceptibility.

Cytokine SNPs: Comparison of allele frequencies by race and implications for future studies

The role of inflammation is being considered in chronic diseases. Previous studies have examined SNPs in a few key inflammatory genes and have included small numbers of African American participants. Variation in the frequencies of inflammatory pathway SNPs may help to explain racial disparities in disease risk. Through a population-based study of 103 African American and 380 Caucasian unrelated, healthy women, we examined the relationships between race and allele frequencies of 70 cytokine and cytokine receptor SNPs. The associations between genotypic and haplotype frequencies and race were also analyzed. Allelic frequencies for 52 out of the 70 SNPs meeting criteria for analysis differed significantly by race. Of the 32 pro-inflammatory and 20 anti-inflammatory SNPs for which the allele frequencies varied significantly by race, variant allele frequency differences between Caucasians and African Americans ranged between 6-37% and 7-53% for pro-inflammatory SNPs and anti-inflammatory SNPs, respectively. Our findings suggest that while allele frequencies do vary by race, racial groups are not simplistically represented by a pro-inflammatory or anti-inflammatory genetic profile. Given the racial variability in allele frequencies in inflammatory gene SNPs, studies examining the association between these SNPs and disease should at least incorporate self-reported race in their analyses.

Immune response and gene polymorphism profiles in Crohn's disease and ulcerative colitis

BACKGROUND

Polymorphisms in genes linked to the innate and adaptive immune response may be involved in inflammatory bowel disease pathogenesis. Our aim was to investigate associations among IL1B-511, IL1B-31, IL1RN, TNFA-307, TLR-2, TLR-4, IL2-330, NOD2 G908R, NOD2 L1007fsinsC polymorphisms and both Crohn's disease (CD) and ulcerative colitis (UC) in a Brazilian population.

METHODS

We studied 43 patients with CD, 42 with UC, and 541 blood donors. Polymorphisms were evaluated by PCR, PCR-CTPP, or PCR-RFLP. Data were analyzed in multivariate models adjusting for confounding factors.

RESULTS

IL1RN VNTR (P = 0.00, odds ratio [OR] = 2.43, 95% confidence interval [CI] = 1.50-3.90), as well as TNFA-307 polymorphic allele (P = 0.05, OR = 1.70, 95% CI = 1.00-2.94) were associated with UC. Both NOD2 mutations (G908R, P = 0.02, OR = 6.83, 95% CI = 1.62-25.45, and L1007fsinsC, P = 0.00, OR = 20.00, 95% CI = 3.21-124.69) were associated with CD.

CONCLUSIONS

Our analyses showed positive associations between proinflammatory polymorphisms at IL1RN and TNFA-307 loci and UC, as well as polymorphisms in the NOD2 gene and CD. These results highlight the importance of different genetic profiles associated with CD and UC.

Involvement of functional polymorphisms in the TNFA gene in the pathogenesis of autoimmune thyroid diseases and production of anti-thyrotropin receptor antibody

The severity of Hashimoto's disease (HD) and intractability of Graves' disease (GD) varies among patients. Severity of HD is associated with the functional +874A/T polymorphism for interferon-gamma, an inflammatory cytokine. To clarify the association between functional polymorphisms in two other inflammatory cytokine genes [tumour necrosis factor (TNF)-alpha and interleukin (IL)-2] and the severity of autoimmune thyroid disease (AITD), we examined the TNF-alpha-1031T/C, TNF-alpha-857C/T and IL-2 -330T/G polymorphisms in genomic DNA samples. We genotyped 41 patients with intractable GD, 34 patients with GD in remission, 41 patients with severe HD, 36 patients with mild HD and 70 healthy controls. The frequency of carriers of TNF-alpha-1031C (CT + CC), which correlates with higher TNF-alpha production, was significantly higher in HD and GD patients than in controls, but was not associated with the severity of HD. In GD patients, the levels of anti-thyrotropin receptor antibody (TRAb) at onset of the disease was higher in patients with the TNF-alpha-857T (CT + TT) genotype, which correlates with higher TNF-alpha production, than in those with the -857CC genotype. We found no differences in the IL-2 -330T/G polymorphism among groups of AITD patients. In conclusion, the functional -1031T/C polymorphism of the TNFA gene is associated with the development of AITD and the functional -857C/T polymorphism is associated with the levels of TRAb in active GD patients.

Polymorphisms of interleukin-1 and interleukin-2 genes in patients with gastric cancer in Korea

BACKGROUND AND AIM

Interleukin (IL)-1 gene polymorphism has been reported to be associated with the increment of gastric cancer (GC) and the decrement of duodenal ulcers (DU). In addition, IL-2 is known to induce Helicobacter pylori (H. pylori)-associated gastric atrophy, but it is not known whether IL-2 gene polymorphism increases the risk of GC (GC) or peptic ulcer diseases. Therefore, we compared the genotypes of IL-1B, IL-1RN, and IL-2 gene polymorphisms with risk of gastric ulcers (GU), GC, and DU in Korean patients.

METHODS

In total, 116 GU, 122 GC, and 104 DU patients were included consecutively and compared with 100 healthy controls. Polymorphisms of the IL-1B-511/-31 gene, the penta-allelic variable number of tandem repeats of the IL-1RN gene, and the IL-2-330 gene were analyzed by polymerase chain reaction with restriction fragment length polymorphism or confronting two-pair primers methods.

RESULTS

The age-sex-adjusted odds ratios (OR) for the IL-1B-511 T genotype relative to the C/C genotype (OR = 0.82, 95% confidence interval [CI] 0.41-1.65), IL-1RN*2 genotype relative to the L/L genotype (OR = 0.85, 95% CI 0.41-1.78), and IL-2-330 T genotype relative to the G/G genotype (OR = 1.94, 95% CI 0.76-4.96) were not increased in GC. There was also no significant difference in the genotypes of these cytokine polymorphisms between the study group (GU or DU) and control group. In addition, genotypic frequency was not associated with H. pylori positivity and histological type of GC.

CONCLUSION

IL-1B-511, IL-1RN, and IL-2 genetic polymorphisms were not important contributors to the pathogenesis of GU, GC, and DU in Korean patients.

A new genetic variant involved in genetic susceptibility to alcoholic liver cirrhosis: -330T>G polymorphism of the interleukin-2 gene

OBJECTIVE

Genetic factors may determine susceptibility to develop alcoholic liver cirrhosis, although it remains uncertain why only a minority of alcoholics suffers from this disease. A decrease in serum levels of interleukin-2 (IL-2) is usually found in alcoholic cirrhotics. In this study we examined the relationship between the -330T>G IL-2 gene (IL2) polymorphism and alcoholic liver cirrhosis.

METHODS

Genotyping of the aforementioned polymorphism was done by polymerase chain reaction and digestion with restriction enzymes in 257 male alcoholics (161 without liver disease and 96 with alcoholic liver cirrhosis) and 101 healthy controls. A logistic regression analysis was performed to adjust for potential confounders and to analyze the model of inheritance.

RESULTS

We found an association between the -330T>G IL2 polymorphism and alcoholic liver cirrhosis: the frequency of the allele T carriers (genotype TT and GT) was significantly higher in alcoholics with cirrhosis (96.9%) than in those without liver disease (89.4%, P=0.043).

CONCLUSION

We report for the first time that the possession of the -330T allele of the IL2 is associated with a higher risk of developing alcoholic liver cirrhosis and this fact may favor the progression of alcoholic liver disease.

Cytokine gene polymorphisms and cytokine levels in pulmonary tuberculosis

Polymorphisms in the cytokine genes are known to influence cytokine levels and may be associated with outcome of infections. We investigated the polymorphisms in the cytokine genes namely IFN-gamma (+874 and +5644), IL-2 (-330 and +160), IL-4 (VNTR), IL-6 (-174), IL-10 (-1082 and -819) and IL-12B (+1188) in 188 normal healthy subjects (NHS) and 166 pulmonary tuberculosis patients (PTB) using polymerase chain reaction-based methods. To study the influence of cytokine gene polymorphisms on cytokine levels, phytohaemagglutinin and culture filtrate antigen of Mycobacterium tuberculosis-induced cytokine levels were measured by ELISA from 72-h-old peripheral blood mononuclear cell culture supernatants. Significantly decreased frequency of TT genotype of IL-2 -330 polymorphism (p=0.024, odds ratio (OR) 0.53, 95% CI 0.31-0.92) was observed in patients compared to NHS. The genotype frequencies of other polymorphisms were not different between patients and NHS. IL-12p40 levels were significantly decreased among NHS with AA genotype of IL-12B gene polymorphism compared to NHS with AC genotype (p<0.05). Increased levels of IL-12p40 were observed among patients with CC genotype of IL-12B gene compared to patients with other genotypes (p<0.01). The present study suggests that the TT genotype of IL-2 -330 polymorphism may be associated with the protection to PTB in south India. Further, +1188 polymorphism of IL-12B gene either alone or in combination with closely linked genes may regulate IL-12p40 production and may play a major role on acquired immunity to tuberculosis.