Cytotoxic T-lymphocyte Antigen-4 Polymorphisms Research Articles

The Relationship Between CTLA-4 (-318 C/T) Polymorphism and Urothelial Cancer Carcinogenesis in Japanese Patients.

Background Urothelial cancer is one of the most common types of urinary system cancer and there are several factors that can influence its growth. One of the most prominent factors among these is genetics. The Cytotoxic T-Lymphocyte Antigen-4 (CTLA-4) gene is suspected to be a susceptibility gene in urothelial carcinoma. The aim of this study is to investigate polymorphism in the CTLA-4 gene (CTLA-4 -318 C/T) and whether it is associated with urothelial cancer. Methods The study population consisted of 253 cases and 272 controls. In this case-control study, DNA was extracted from peripheral blood cells, and the CTLA-4 -318C/T genotypes were detected using polymerase chain reaction-restriction fragment length polymorphism. Results C/T (adjusted OR (aOR) 3.37; 95%CI: 1.98-5.74) genotype, C/T + T/T (aOR 3.25; 95%CI: 1.96-5.39) genotype, and T allele (aOR 2.94 95%CI: 1.87-4.62) all indicated they are significant risk factors for urothelial cancer, with the effects of polymorphism being higher in the nonsmoker group than in the smoker group. Furthermore, the association between polymorphism and urothelial cancer carcinogenesis was similar among men and women. Conclusions This is the first study examining the association between CTLA-4 -318C/T polymorphism and urothelial carcinoma in Japanese patients. A significant association between CTLA-4 -318C/T polymorphism and urothelial cancer among Japanese patients was detected in this study. This supports the development of research on polymorphisms in urothelial cancer and is an important root of immunoreactions in cancer. We believe this study will be beneficial to clarify the relationship between CTLA-4 polymorphism and urothelial cancer.

Unveiling the Etiopathogenic Spectrum of Hypophysitis: A Narrative Review.

Hypophysitis, a rare inflammatory disorder of the pituitary gland, has seen an uptick in reported cases in recent years. Our objective is to summarize the most recent research on the etiopathogenesis, molecular mechanisms, and genetics of both primary and secondary hypophysitis. Primary autoimmune hypophysitis (PAH): During the acute phase of the disease, the pituitary gland in enlarged due to the infiltration of T and B lymphocytes. The chronic phase is characterized by progressive and irreversible pituitary atrophy. APA may play a role in the management, diagnosis, and prognosis of PAH. Specific autoantibodies such as anti-GH, anti-PIT-1, and anti-T-PIT have been found in patients with hypophysitis and hypopituitarism. A recent study suggested that a mechanism of escaping clonal deletion and mounting an immune response against self antigens can explain the unusual nature of the immune response observed in PAH patients. A cytokine array shows the presence of gamma-interferon and interleukin-17. Patients carrying mutations in the PIT1 or PROP1 genes may present PAH. Individuals carrying the HLA DQ8 haplotype are four times more likely to develop PAH. Immune checkpoint inhibitors induce hypophysitis (IIHs): IIHs is an increasingly frequent toxicity of in patients on treatment with inhibitors targeting cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death-1 (PD-1). ICIs inhibit the CTLA-4 pathway, leading to overactivation of T lymphocytes. The binding of PD-1/PD-L1 suppresses the activity of T cells, promotes the conversion of T-helpers into T-regulatory cells, and activates pro-survival signaling pathways in cancer cells. Cytokines play a crucial role in IIHs. B-cell infiltration has been observed in IIHs, suggesting that antibody-mediated pituitary injury may contribute. Genetic polymorphisms of CTLA-4 and PD-1 genes can increase the risk of IIHs. HLA alleles may also be involved in the onset of IIHs; this HLA association presents a possible alternative mechanistic hypothesis. IIHs may also be linked to a paraneoplastic syndrome triggered by ectopic expression of pituitary specific antigens. SARS-CoV-2-related hypophysitis: Recently, the literature has reported occurrences of hypophysitis associated with the SARS-CoV-2 virus; long COVID-19 may also present as infundibulo-neuro-hypophysitis. The virus enters the central nervous system because of its distinct interaction with angiotensin-converting enzyme receptors via spike proteins binding the capillary endothelium, and it directly damages the pituitary cells. The effect of SARS-CoV-2 can occur indirectly through inflammation and the release of cytokines. The exact mechanism remains ambiguous. The available data on endocrine complications associated with the SARS-CoV-2 vaccine are scant. Nonetheless, isolated cases of hypophysitis have been documented. Treatment of hypophysitis: Glucocorticoids are the cornerstone in managing primary hypophysitis, given their targeted action on inflammation. A better understanding of the etiopathogenesis and molecular mechanism of hypophysitis can lead to more effective and personalized treatment strategies.

Polymorphisms in CTLA-4 predict de novo donor specific antibody formation after kidney transplantation

The post-transplant development of donor-specific antibodies (DSAs) initiates the antibody-mediated rejection, which is associated with an increased rate of graft loss. Therefore, risk prediction of de novo DSA (dnDSA) is important for understanding long-term prognostic implications for kidney transplantation outcomes. Cytotoxic T lymphocyte antigen-4 (CTLA-4), a cell surface molecule, suppresses T cell responses. Single-nucleotide polymorphisms (SNPs) in CTLA-4 are known to be associated with acute rejection; however, their association with dnDSA formation is not established. In the present study, we investigated the impact of CTLA-4 SNPs on dnDSA formation after kidney transplantation (KT) by analyzing three CTLA-4 SNPs (rs231775, rs3087243, and rs5742909) in 88 recipients. Patients with the GG genotype of CTLA-4 SNPs rs231775 and rs3087243 had higher rates of dnDSA formation than patients with the AA genotype or heterozygous genotypes. In conclusion, our findings indicate that CTLA-4 SNPs are predisposing factors for dnDSA formation after KT.

CTLA-4 polymorphism contributes to the genetic susceptibility of epithelial ovarian cancer.

Cytotoxic T-lymphocyte antigen-4 (CTLA-4), an inhibitory molecule on T-cells, plays a key role in tumorigenesis and progression. In the present study, we investigated the effects of three polymorphisms in the CTLA-4 gene on the risk of epithelial ovarian cancer and the clinical outcomes of patients. A case-control study was performed in 527 epithelial ovarian cancer patients and 532 controls. Genotypes of three polymorphisms were determined by polymerase chain reaction/ligase detection reaction. A survival analysis was performed in 346 patients who were followed up for more than 3 years and 208 patients who were followed up for more than 5 years. There were significant differences in the genotype and allele distribution frequencies of the rs5742909 C/T polymorphism in CTLA-4 between patients and controls (p=0.009 and p=0.04, respectively). Compared with the CC genotype, the CT + TT genotype may significantly decrease the risk of developing epithelial ovarian cancer (OR=0.69, 95% CI=0.52-0.91). However, no significant association between the rs231775 G/A and rs3087243 G/A polymorphisms and epithelial ovarian cancer risk was observed. The survival analysis showed that three polymorphisms may not be related to the clinical outcomes of patients. Our results suggested that the rs5742909 C/T polymorphism of CTLA-4 may decrease the genetic susceptibility to epithelial ovarian cancer among northern Chinese women.

Meta-Analysis of the Genetic Association between PTPN22 and CTLA-4 Variants and Risk of Uveitis

Background: Though the risk of protein tyrosine phosphatase nonreceptor 22 (PTPN22) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) genetic variants with uveitis have been developed, the combined results still remain uncertain and controversial. Objectives: The aim of this study was to perform a meta-analysis to estimate the precise association of PTPN22 (rs2488457 and rs2476601) and CTLA-4 (rs231775, rs5742909, rs4553808, and rs3087243) polymorphisms with uveitis susceptibility. Method: Five electronic databases (PubMed, Embase, Web of Science, China Biomedical Database, and China National Knowledge Infrastructure) were systematically searched for relevant literature up to July 20, 2021. All statistical analyses were evaluated by Stata 12.0 software and R programming language. Results: Our meta-results indicated that PTPN22 rs2488457 conferred positive susceptibility to uveitis (odds ratio [OR] = 1.18, 95% confidence interval [CI] = 1.02–1.38, p = 0.029). In stratified analysis by ethnicity, the rs2488457 C allele had a growing tendency toward uveitis in the Asian region (OR = 1.21, 95% CI = 1.00–1.45, p = 0.046). For CTLA-4 rs231775, subgroup analysis based on ethnicity manifested a negative association among uveitis individuals in the Africa region (OR = 0.25, 95% CI = 0.19–0.33, p < 0.001). For CTLA-4 rs4553808, subgroup analysis by the disease type revealed that the GG genotype was associated with an elevated risk of Behcet’s disease (BD) (OR = 3.22, 95% CI = 1.05–9.90, p = 0.042). Conclusions: Our research revealed that PTPN22 rs2488457 conferred strong susceptibility to uveitis in general, especially in the Asian region. CTLA-4 rs231775 conveyed protection against uveitis in African populations, and CTLA-4 rs4553808 displayed an increased risk of BD.

Association of CTLA-4 (+49 A/G) polymorphism with susceptibility to autoimmune diseases: A meta-analysis with trial sequential analysis

ObjectivesIn recent years, more and more studies have been focusing on the association between Cytotoxic T lymphocyte antigen-4 (CTLA-4) (+49 A/G) gene polymorphism and autoimmune diseases. However, the results of previous studies are still controversial. The meta-analysis is aiming at determining the association in CTLA-4 (+49 A/G) gene rs231775 polymorphism and ankylosing spondylitis (AS), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE). MethodsWe searched PubMed, Web of Science, Chinese National Knowledge Infrastructure (CNKI) and Chinese Biomedical Database (CBM) up to November 2020, use random or fixed-effect models to perform meta-analysis to compare alleles and other genetic models, including homozygous, heterozygous, recessive and dominant models. The odds ratio (OR) with a 95% confidence interval (95% CI) was used to assess the correlation between CTLA-4 (+49 A/G) gene polymorphism and the genetic affectability of AS, RA, and SLE. Meanwhile, we used sequential trial analysis (TSA) to analyze the reliability of the results. Finally, we searched the relevant data of genome-wide association studies (GWAS) to further verify the accuracy of the experimental results. Results47 studies with 11,893 cases and 12,032 healthy controls were included. The rs231775 G allele was relevant to high risk of autoimmune disease over all people (P < 0.05). The G allele of rs231775 was significantly related to RA susceptibility (P < 0.05), but not with AS or SLE. Subgroup analysis by ethnicity indicated that rs231775 G allele was closely related to RA in Caucasian populations and Mongolian populations (P < 0.05). A strong connection within rs231775 G allele and AS affectability was uncovered in Caucasian populations (P < 0.05). The analysis of the TSA shows that the meta-analysis can draw the conclusion. ConclusionCTLA-4 (+49 A/G) gene rs231775 G allele increases the risk of autoimmune diseases in Caucasian populations. And it also increases the risk of RA in Caucasian and Mongolian populations. More sample size and more elaborately designed studies are needed to elucidate the relationship in CTLA-4 (+49 A/G) gene rs231775 G allele and autoimmune diseases, especially AS, SLE.

CTLA-4 +49 A/G Polymorphism and the Risk of Lung Cancer: a Meta-analysis.

Background and objectiveLung cancer is one of the malignant tumors. Gene mutations associated with cellular immune function and regulating the activation and proliferation of immune cells. Several publications have explored the relationship between cytotoxic T lymphocyte antigen-4 (CTLA-4) +49 adenine (A)/guanine (G) polymorphism and susceptibility of lung cancer, but the results remain controversial. Thus, we performed this meta-analysis to derive a more comprehensive estimation of the relationship.MethodsAll articles addressed lung cancer and polymorphisms of CTLA-4 were searched from the PubMed, EMBASE databases published up to June 29, 2019. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. Publication bias of relevant studies was examined via Begg's test and funnel plots.ResultsThe meta-analysis included 8 case-control studies covering 4, 430 lung cancer patients and 5, 198 healthy controls from September 2008 to April 2020. The overall eligible data indicated that CTLA-4 +49A/G polymorphisms did not correlate with the elevated lung cancer risk in all genetic comparison models (dominant model: OR=1.037, 95%CI: 0.925-1.161; recessive model: OR=0.968, 95%CI: 0.888-1.055; allele model: OR=0.992, 95%CI: 0.933-1.054; homozygous model: OR=0.980, 95%CI: 0.857-1.121; heterozygous model: OR=1.023, 95%CI: 0.906-1.154). In further stratified analyses, CTLA-4 +49A/G polymorphism was found to be significantly associated with susceptibility to NSCLC in these models (dominant model: OR=1.404, 95%CI: 1.074-1.836; allele model: OR=1.273, 95%CI: 1.034-1.565; homozygous model: OR=1.553, 95%CI: 1.044-2.310; heterozygous model: OR=1.308, 95%CI: 1.062-1.611).ConclusionCTLA-4 +49A/G polymorphism were not associated with the risk of lung cancer but might be a risk factor only in NSCLC.

Association of cytotoxic T-lymphocyte antigen-4 (CTLA-4) single nucleotide polymorphism in donors with clinical outcome after allogeneic hematopoietic stem cell transplantation: a meta-analysis

ABSTRACT Objective Cytotoxic T-lymphocyte antigen 4 (CTLA-4) polymorphisms at positions of +49 and CT60 in donors have been reported to influence clinical outcome following allogeneic hematopoietic stem cell transplantation (allo-HSCT), such as overall survival (OS), disease free survival (DFS), relapse and the risk of graft versus host disease (GVHD). However, the results still remain controversial. Thus, we conducted the first meta-analysis to get a more accurate estimation of the relationship between CTLA-4 genotype and the above end points. Methods PubMed, Embase, Web of science and Cochrane Library were searched to select eligible studies, data were extracted and then combined ORs/HRs together with the corresponding 95% confidence intervals (CIs) were calculated. Both the dominant and recessive models were employed to evaluate the associations between genetic variation in donor CTLA-4 and outcome after allo-HSCT. Results A total of 15 studies were included the pooled results indicated that +49 GG homozygote in donors was significantly associated with increased risk of chronic GVHD (OR=1.701, 95% CI, 1.124-2.573, P=0.012, I2=34.7%). With regard to CT60 polymorphism, donors with G allele correlated with worse OS (HR = 1.422, 95% CI, 1.080-1.872, P=0.012, I2=0%) and lower susceptibility to severe acute GVHD (HR=0.619, 95% CI, 0.426-0.899, P=0.012, I2=0%). There was no significant association between CTLA-4 polymorphism and DFS or the incidence of relapse. Conclusions The present meta-analysis suggests that donors with CT60 G allele might be associated with worse OS but reduced severe aGVHD occurrence, while patients transplanted from donors with GG genotype at position of +49 are more likely to suffer from cGVHD.

Determination the CTLA-4 and PTPN22 Gene Polymorphism in Graves’ Disease Patients

Graves’ disease (GD) is a multifactorial autoimmune disease with contribution from both genetic andepigenetic factors in its causation. Gene “protein tyrosine phosphatase non receptor 22” (PTPN22) is animportant immune regulatory gene preventing hyper responsiveness of T cells by negatively regulatingtheir signal transduction. Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) gene polymorphisms belong to themain genetic factors determining the susceptibility to development Graves’ disease. This study aimed toanalyze whether 1858 C/T SNP in PTPN22 and 1822 C/T SNP in CLTA-4 genes have any association withGD in Iraqi population. PCR-RFLP was performed for genotyping 1858 C/T SNP and 1822 C/T SNP withinPTPN22 and CLTA-4 respectively, in patients with GD and healthy controls. Among the patients with GD,the frequencies CLTA-4 CC, CT, and TT genotypes were 43.3%, 45%, and 11.6%, respectively, whereas inhealthy controls the frequencies of CC, CT genotypes were 60%, 30%, and 10%, respectively. While thereis no mutation recorded in PTPN22 1858 C/T SNP in both PCR-RFLP and DNA sequence analysis. Theseresults indicated that there is no significant association was found between PTPN22 1858 C/T SNP andCLTA-4 in patients with GD. It has been concluded that GD is not associated with PTPN22 1858 C/T SNPand 1822 C/T SNP of CLTA-4 in Iraqi population.

Lack of Association Between CTLA-4 Genetic Polymorphisms and Noncardiac Gastric Cancer in a Chinese Population.

Cytotoxic T lymphocyte antigen 4 (CTLA-4) is a key negative immunoregulatory molecule with characteristics of gene polymorphisms. Genetically predisposed CTLA-4 alteration in humans was associated with gastric cancer (GC) development. To explore the association of CTLA-4 polymorphism with susceptibility of noncardiac GC (NCGC), 490 NCGC patients and 1476 control individuals were studied. Four CTLA-4 polymorphisms were genotyped with SNPscan genotyping assays and the haplotypes were constructed with SHESIS software. Frequencies of the CTLA-4 haplotypes were estimated using an expectation-maximization algorithm. The CTLA-4 polymorphism genotype distribution and allele frequencies were not significantly different between the NCGC patients and the control subjects. The CTLA-4 haplotypes did not exhibit a significantly increased risk for NCGC patients. Adjusting status of age, sex, smoking status, alcohol use, and body mass index could not moderate any of the relationships. Data suggested that CTLA-4 polymorphisms (rs3087243, rs16840252, rs733618, and rs231775) were not significantly associated with the risk of NCGC in this Chinese population studied.

CTLA-4 polymorphism rs231775: Influence on relapse and survival after allogeneic hematopoietic stem cell transplantation in childhood.

Relapse following allogeneic hematopoietic stem cell transplantation (HSCT) is still linked to a poor prognosis. Mainly, donor`s T-cells mediate the graft-versus-leukemia effect. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is an inhibitory molecule which down-regulates T-cell activation. Single nucleotide polymorphism (SNP) in CTLA-4 may have an effect on immune response. Eighty-eight children with acute leukemia and their donors were genotyped of CTLA-4 gene for rs231775. We searched for an association of CTLA-4 SNP with relapse and survival after allogeneic HSCT. We identified a significantly reduced relapse rate in children who received a transplant from a donor with the CTLA-4 genotypes AG or GG in comparison with genotype AA of rs231775 (19% vs 40%, P=0.026). In addition, we observed a significant difference in event-free survival (EFS) depending on the donor´s genotype. The EFS was 70% or 46% if the patient was transplanted from a donor with CTLA-4 genotype AG/GG or AA, respectively (P=0.025). In multivariate analysis, CTLA-4 genotype was an independent risk factor for relapse rate (P=0.028). This study suggests that CTLA-4 polymorphism rs231775 is relevant for relapse and survival after allogeneic HSCT in childhood and should be further investigated in clinical trials.

Association of Cytotoxic T Lymphocyte Antigen-4 Gene Polymorphisms with Psoriasis Vulgaris: A Case-Control Study in Turkish Population.

Psoriasis is a common, chronic, and autoimmune skin disease in which dysregulation of immune cells, particularly T cells, is thought to play an important role in the pathogenesis. Cytotoxic T lymphocyte antigen-4 (CTLA-4) expressed only on activated T cells is an immunoregulatory molecule and plays a role in the pathogenesis of autoimmune disorders. We aimed to determine whether CTLA-4 gene polymorphisms are associated with development and/or clinical features of psoriasis vulgaris (Pv). Genotyping of SNPs (−318C>T, +49A>G, and CT60A>G) in CTLA-4 gene was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 103 Pv patients and 102 controls. No statistically significant associations were detected in any of the investigated genetic models for the −318C>T polymorphism. The genotype distributions of +49A>G and CT60A>G were associated with Pv development. In haplotype analysis, while frequency of CAA haplotype was significantly higher in the control group, frequencies of CGG and CAG haplotype were significantly higher among the patients. However, all of CTLA-4 polymorphisms and haplotypes do not have an effect on severity and onset age of Pv. In conclusion, the +49A>G and CT60A>G polymorphisms may be risk factors for Pv development. Furthermore, CGG and CAG haplotypes may contribute to Pv development, while CAA haplotype may be protective against Pv.

CTLA-4 polymorphisms are associated with treatment outcomes of patients with multiple myeloma receiving bortezomib-based regimens.

Single-nucleotide polymorphisms (SNPs) of cytotoxic T lymphocyte antigen-4 (CTLA-4) are important risk factors associated with autoimmune diseases and malignancies. This study explored the association of CTLA-4SNPs with the development of myeloma and evaluated the outcome of patients receiving bortezomib-based regimens in relation to CTLA-4SNPs. Peripheral blood samples from 86 patients with multiple myeloma (MM) and 154 healthy controls were obtained to investigate CTLA4 polymorphisms. Five SNP genotypes of CTLA-4, namely, -1772 (rs733618), -1661 (rs4553808), -318 (rs5742909), CT60 (rs3087243), and +49 (rs231775), were evaluated through TaqMan SNP genotyping assays (Applied Biosystems). Some of the CTLA-4 polymorphisms displayed frequencies that vary among ethnic groups. Kaplan-Meier analysis revealed that patients with rs733618 GG showed a significantly lower disease-free survival (0 vs. 57.4%, P = 0.020) and overall survival (46.3 vs. 83.3%, P = 0.026) than those with GA+AA following bortezomib-based therapy. Multivariate analyses showed that rs733618 GG was a risk factor for OS (HR = 0.012; 95% CI = 0.001-0.199; P = 0.002). The incidence of nonhematologic grade 3/4 adverse events significantly increased in the rs4553808 GG+GA group compared with that in the AA group (P = 0.036). CTLA-4 rs733618 GG reduced the progression-free survival and the overall survival of patients with MM who received bortezomib-based therapy. Information regarding CTLA-4 polymorphisms and haplotypes may be used to improve MM therapy. Future studies must determine the precise effect of CTLA-4 polymorphisms and haplotypes on MM therapy outcomes by using different cohorts with a large number of subjects.

CTLA-4 polymorphisms associate with breast cancer susceptibility in Asians: a meta-analysis.

Previous studies have investigated the association between cytotoxic T-lymphocyte antigen-4 (CTLA-4) polymorphisms and breast cancer susceptibility, but the results remained inconsistent. Therefore, we evaluated the relationship between four common CTLA-4 polymorphisms and breast cancer risk by a meta-analysis, aiming to derive a comprehensive and precise conclusion. We searched EMBASE, Pubmed, Web of Science, CNKI, and Wanfang databases until July 18th, 2016. Finally, ten eligible studies involving 4,544 breast cancer patients and 4,515 cancer-free controls were included; all these studies were from Asia. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the breast cancer risk in five genetic models. The results indicated that the CTLA-4 +49A>G (rs231775) polymorphism had a significant association with decreased breast cancer risk in allelic, homozygous, dominant and recessive models. Also, the +6230G>A (rs3087243) polymorphism reduced breast cancer risk especially in the Chinese population under homozygous and recessive models. In contrast, the −1661A>G (rs4553808) polymorphism increased breast cancer risk in allelic, heterozygous and dominant models, whereas −1722 T>C (rs733618) did not relate to breast cancer risk. In conclusion, CTLA-4 polymorphisms significantly associate with breast cancer susceptibility in Asian populations, and different gene loci may have different effects on breast cancer development. Further large-scale studies including multi-racial populations are required to confirm our findings.

CTLA-4 Polymorphisms: Influence on Transplant-Related Mortality and Survival in Children Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

Background: Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative approach for a variety of hematologic diseases but is still associated with substantial morbidity and mortality. Transplant-related mortality (TRM) after HSCT depends mainly on the toxicity of the conditioning regimen, infections, and graft-versus-host disease (GVHD). Polymorphisms at major histocompatibility complex MHC) have been proven to be critical for successful allogeneic HSCT. Polymorphisms at non-MHC loci have been associated with HSCT outcome as well. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is an inhibitory molecule that down-regulates T-cell activation. The purpose of this study was to identify an association between CTLA-4 single nucleotide polymorphisms (SNPs) and TRM in children undergoing allogeneic HSCT.Methods: 153 donors and 153 children (median age, 11 years) with acute lymphoblastic leukemia (n=90), acute myeloid leukemia (n=58) or juvenile myelomonocytic leukemia (n=5) who underwent allogeneic HSCT in a single center were genotyped of CTLA-4 gene for rs3087243 (CT60 A/G), rs231775 (+49 A/G) and rs4553808 using TaqMan real-time polymerase chain reaction. 49 children were transplanted in first, 40 children in second and 15 in third complete remissions. 49 patients did not reach complete remission at the time of transplantation. The donor was HLA-matched unrelated in 59% of transplants and HLA-identical related in 41% of transplants. Conditioning regimen was myeloablative in all cases and based on total body irradiation in 52% of transplants or busulfan in 44% of transplants. Two forms of post-transplant immunosuppression predominated, cyclosporine A and methotrexate in 64% of transplants and cyclosporine A alone in 25% of transplants.Results: We observed a significant association between the donor´s CTLA-4 genotype of rs3087243 and TRM in children undergoing allogeneic HSCT. Genotype AG of CTLA-4 rs3087243 SNP was found in 78 donors (51%), GG in 44 donors (29%), and 31 donors were homozygous for AA (20%). 30 patients died of transplant-related causes. 16 patients died of multi-organ failure, 7 of infection, 3 of acute GVHD, 2 of chronic GVHD, and 2 of hepatic sinusoidal obstruction syndrome. Interestingly, we observed a significantly reduced TRM in children who were transplanted from a donor with the CTLA-4 genotype GG in comparison to genotype AG or AA of rs3087243 (9% versus 19% versus 36%, p=0.013). In addition, we found significant differences of event-free survival (EFS) depending on the donor´s genotype. The EFS was 64%, 46% or 32% if the patient was transplanted from a donor with CTLA-4 genotype GG, AG or AA of rs3087243, respectively (p=0.043). In multivariate analysis, CTLA-4 genotype of rs3087243 was an independent risk factor for TRM (0.021). The CTLA-4 genotypes, in either donors or recipients, had no significant impact on relapse rate, acute and chronic graft-versus host disease.Conclusions: This study provides the first evidence that the CTLA-4 polymorphisms are significant risk factors for TRM and survival in children undergoing allogeneic HSCT and should be evaluated in further trials. DisclosuresNo relevant conflicts of interest to declare.

Association of CTLA-4 gene polymorphisms -318C/T and +49A/G and Hashimoto's thyroidits in Zahedan, Iran.

Hashimoto's thyroiditis (HT) is a chronic inflammation of the thyroid gland and is known as the most common autoimmune disease. Development of autoimmune destruction of thyroid cells is a multi-step process involving convergence of genetic and environmental factors. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) has an important role in homeostasis and negative regulation of immune responses, and is therefore considered to be a key element in the development of autoimmune diseases. The present study evaluated the association of the CTLA-4 gene polymorphisms 318C/T (rs5742909) and +49A/G (rs231775) with HT in an Iranian population (including 82 patients with HT and 104 healthy controls who were referred for routine premarital blood screenings). Genotyping was performed using the tetra-primer amplification refractory mutation system polymerase chain reaction technique. No significant differences were observed in genotype and allele frequencies in the single nucleotide polymorphisms (SNPs) between cases and controls. In the cases as well as in the controls, the TT genotype in the -318C/T polymorphism was absent and the predominant genotype was CC, while the predominant genotype for the +49A/G SNP was AA. As only few studies in this field have assessed Iranian and even Middle Eastern populations, additional studies with a higher number of samples are recommended to further assess the impact of -318C/T (rs5742909) and +49A/G (rs231775) polymorphisms of CTLA-4 on HT.

Association of Cytotoxic T-Lymphocyte Antigen 4 (CTLA4) and Thyroglobulin (TG) Genetic Variants with Autoimmune Hypothyroidism.

Autoimmune hypothyroidism is known to be caused by immune responses related to the thyroid gland and its immunological feature includes presence of autoimmune antibodies. Therefore the aim was to analyze presence of anti-TPO antibodies in hypothyroidism patients in Gujarat. Cytotoxic T-Lymphocyte Antigen 4 (CTLA4) is one of the susceptibility genes for various autoimmune diseases. Hence, exon1 +49A/G and 3’UTR CT60A/G single nucleotide polymorphisms (SNPs) in CTLA4 and its mRNA expression levels were investigated in autoimmune hypothyroidism patients. Thyroglobulin (TG) is known to be associated with autoimmune thyroid disorders and thus exon 33 (E33) SNP in TG was investigated. We analyzed the presence of anti-TPO antibodies in the plasma samples of 84 hypothyroidism patients and 62 controls by ELISA. PCR-RFLP technique was used for genotyping of polymorphisms. sCTLA4 and flCTLA4 mRNA expression levels were assessed by real time PCR. 59.52% of hypothyroid patients had anti-TPO antibodies in their circulation. The genotype and allele frequencies differed significantly for +49A/G (p = 0.0004 for +49AG, p = 0.0019 for +49GG & p = 0.0004 for allele), CT60 (p = 0.0110 for CT60AG, p = 0.0005 for CT60GG & p<0.0001 for allele) and TG E33 (p = 0.0003 for E33TC p<0.0001 for E33CC& p<0.0001 for allele) SNPs between patients and controls. Patients had significantly decreased mRNA levels of both sCTLA4 (p = 0.0017) and flCTLA4 (p<0.0001) compared to controls. +49A/G and CT60 polymorphisms of CTLA4 were in moderate linkage disequilibrium. Logistic regression analysis indicated significant association of CT49A/G, CT60A/G and TG exon 33 polymorphisms with susceptibility to autoimmune hypothyroidism when adjusted for age and gender. Our results suggest +49A/G and CT60 polymorphism of CTLA4 and E33 polymorphism of TG may be genetic risk factors for autoimmune hypothyroidism susceptibility and down regulation of both forms of CTLA4 advocates the crucial role of CTLA4 in pathogenesis of autoimmune hypothyroidism.

Investigation of Cytotoxic T-lymphocyte antigen 4 Polymorphisms in Gastric Cardia Adenocarcinoma.

To assess the potential effects of Cytotoxic T-lymphocyte antigen 4 (CTLA4) gene polymorphisms on susceptibility to gastric cardia adenocarcinoma (GCA), we genotyped four polymorphisms (rs733618 A>G, rs16840252 C>T, rs231775 G>A and rs3087243 G>A) in CTLA4 and calculated odds ratios (ORs) with the corresponding 95% confidence intervals (95% CIs) for the genotype and allele distributions between GCA cases and controls. The CTLA4 genotypes were determined by the polymerase chain reaction-ligase detection reaction (PCR-LDR) analysis in 330 GCA patients and 608 unrelated cancer-free controls. In this case-control study, there was no significant difference in the genotype and allele distributions of four CTLA4 polymorphisms between GCA patients and controls. However, haplotype association analysis indicated that compared with CTLA4 Grs733618 Crs16840252 Grs231775 Crs3087243 , CTLA4 Grs733618 Crs16840252 Ars231775 Grs3087243 and Ars733618 Crs16840252 Grs231775 Ars3087243 haplotypes conferred increased risks of GCA (OR = 6.46, 95% CI = 1.33-31.28; P = 0.012; both); however, CTLA4 Ars733618 Crs16840252 Ars231775 Grs3087243 and Ars733618 Trs16840252 Grs231775 Grs3087243 haplotypes conferred decreased risks of GCA (P = 0.001 and P = 0.011, respectively). These results highlight that the rare CTLA4 haplotypes may affect the development of GCA in the Chinese population.

Association of CTLA-4 (+49A/G) gene polymorphism with type 1 diabetes mellitus in Egyptian children

Objective The aim of the study was to investigate the distribution of cytotoxic T-lymphocyte antigen-4 (CTLA-4) (+49A/G) gene variants and its association with type 1 diabetes (T1D) in Egyptian children. Background T1D is a complex autoimmune disease characterized by T-cell-mediated destruction of the pancreatic island. Human leukocyte antigen (HLAs) account for about 60% of genetic susceptibility for the disease. About 20 non-HLA loci contributing to disease susceptibility have been identified. One among these is the CTLA-4 gene. CTLA-4 polymorphisms are associated with T1D in some but not all populations. The aim of our study was to investigate the frequency of CTLA-4 49A/G polymorphism in Egyptian children, and its susceptibility for development of T1D. Materials and methods A case-control study was conducted on 40 Egyptian children with T1D diagnosed according to ADA (2010). Their ages ranged from 1 to 16 years, with a mean of 8.76 ± 4.70 years; 15 were male and 25 were female. In addition, 20 age and sex-matched healthy controls were included. CTLA-4 (+49A/G) gene polymorphism typing was done by PCR amplification, followed by restriction fragment length polymorphism. Results The frequency of CTLA-4 polymorphisms (AA, AG, and GG) in T1D patients was 42.5, 52.5, and 5% versus 60, 40, and 0% in controls, respectively, with predominance of the AG variant in diabetic patients. Distributions of the CTLA-4 gene polymorphism on the basis of sex showed a normal pattern. The AA genotype was present in 64.7% of female diabetic patients versus 35.3% of male patients, whereas the heterozygous AG genotype was seen in 57.1% of female patients versus 42.9% of male patients, and the homozygous GG genotype was present in two female patients (5%) and was not recognized in male patients; the female predominance can be explained by steroid hormone association. Conclusion In this study the overall pooled prevalence of the CTLA4 (+49A/G) polymorphism was recognized but still not a risk susceptibility factor for T1D in Egyptian children.

Analysis of DLA-DQB1 and polymorphisms in CTLA4 in Cocker spaniels affected with immune-mediated haemolytic anaemia.

BackgroundCocker spaniels are predisposed to immune-mediated haemolytic anaemia (IMHA), suggesting that genetic factors influence disease susceptibility. Dog leukocyte antigen (DLA) class II genes encode major histocompatibility complex (MHC) molecules that are involved in antigen presentation to CD4+ T cells. Several DLA haplotypes have been associated with autoimmune disease, including IMHA, in dogs, and breed specific differences have been identified. Cytotoxic T lymphocyte antigen 4 (CTLA4) is a critical molecule involved in the regulation of T-cell responses. Single nucleotide polymorphisms (SNPs) in the CTLA4 promoter have been shown to be associated with several autoimmune diseases in humans and more recently with diabetes mellitus and hypoadrenocorticism in dogs. The aim of the present study was to investigate whether DLA-DQB1 alleles or CTLA4 promoter variability are associated with risk of IMHA in Cocker spaniels.ResultsThere were a restricted number of DLA-DQB1 alleles identified, with a high prevalence of DLA-DQB1*007:01 in both groups. A high prevalence of DLA-DQB1 homozygosity was identified, although there was no significant difference between IMHA cases and controls. CTLA4 promoter haplotype diversity was limited in Cocker spaniels, with all dogs expressing at least one copy of haplotype 8. There was no significant difference comparing haplotypes in the IMHA affected group versus control group (p = 0.23). Homozygosity for haplotype 8 was common in Cocker spaniels with IMHA (27/29; 93 %) and in controls (52/63; 83 %), with no statistically significant difference in prevalence between the two groups (p = 0.22).ConclusionsDLA-DQB1 allele and CTLA4 promoter haplotype were not found to be significantly associated with IMHA in Cocker spaniels. Homozygosity for DLA-DQB1*007:01 and the presence of CTLA4 haplotype 8 in Cocker spaniels might increase overall susceptibility to IMHA in this breed, with other genetic and environmental factors involved in disease expression and progression.