CD4+ T helper cells and regulatory T cells in active lupus nephritis: an imbalance towards a predominant Th1 response?

The objective of this study was to evaluate the frequency of CD4⁺ T cell subsets in peripheral blood mononuclear cells (PBMC), urine and renal tissue from patients with lupus nephritis (LN). PBMC and urinary cells were collected from 17 patients with active LN, 20 disease controls (DC) with primary glomerulonephritis and 10 healthy controls (HC) and were analysed by flow cytometry with markers for T helper type 1 (Th1), Th2, Th17 and regulatory T cells (T_reg) cells. T cell subsets were assessed by immunohistochemistry from LN biopsy specimens from 12 LN patients. T cell subtypes in PBMC were re‐evaluated at 6 months of therapy. CD4⁺ T cells were decreased in PBMC in LN compared with DC and HC (P = 0·0001). No differences were observed in urinary CD4⁺ T cell subsets between LN and DC. The frequency of urinary Th17 cells was higher in patients with non‐proliferative than in proliferative LN (P = 0·041). CD3⁺ and T‐box 21 ( ) cells were found in glomeruli and interstitium of LN patients, while forkhead box protein 3 (FoxP3), retinoid‐related orphan receptor gamma (ROR‐γ) and GATA binding protein 3 (GATA‐3) were present only in glomeruli. Th1 cells in PBMC were correlated negatively with urinary Th1 cells (Rho = –0·531; P = 0·028) and with T_bet in renal interstitium (Rho = –0·782; P = 0·004). At 6 months, LN patients showed an increase in Th17 cells in PBMC. In conclusion, the inverse association between Th1 cells from PBMC and urinary/renal tissue indicate a role for Th1 in LN pathophysiology. Urinary Th17 cells were associated with less severe LN, and Th17 increased in PBMC during therapy. Urinary CD4⁺ T cells were not different between LN and DC.     

Impaired Thymic Output in Patients with Chronic Hepatitis C Virus Infection

Altered T cell homeostasis in chronic hepatitis C virus (HCV) infection has been demonstrated. However, it is unknown whether fibrosis is associated with more perturbed T cell homeostasis in chronic HCV infection. The aim of this study was to examine and compare T cell subsets including recent thymic emigrants (RTE), naive, memory, senescent, apoptotic and IL‐7 receptor α (CD127) expressing CD4⁺ and CD8⁺ T cells as well as telomere length and interferon‐γ production in HCV‐infected patients with (n = 25) and without (n = 26) fibrosis as well as in healthy controls (n = 24). Decreased proportions of CD4⁺ and CD8⁺ RTE were found in HCV‐infected patients, especially in HCV‐infected patients with fibrosis (14.3% (9.7–23.0) and 28.8% (16.1–40.5), respectively) compared with healthy controls (24.2% (16.3–32.1), P = 0.004 and 39.1% (31.6–55.0), P = 0.010, respectively). Furthermore, HCV‐infected patients with fibrosis presented with a higher proportion of CD4⁺ T cells expressing CD127 compared with HCV‐infected patients without fibrosis [88.4% (84.5–91.0) versus 83.8% (79.9–86.8), P = 0.016]. Thus, impaired thymic output in HCV infection was found, and high proportion of CD127⁺ T cells may illustrate a compensatory mechanism to preserve T cell counts.     

IFN‐γ +874T/A polymorphism increases susceptibility to post‐traumatic osteomyelitis

Immunological inflammatory reaction is one of the key links in the occurrence and development of post‐traumatic osteomyelitis after microbial invasion. Growing evidence suggests complex interactions between IFN‐γ and bone remodelling cells. However, potential association of IFN‐γ gene polymorphism with susceptibility to post‐traumatic osteomyelitis remains unclear. This study aimed to investigate the potential link between IFN‐γ +874T/A polymorphism and risk of developing post‐traumatic osteomyelitis. A total of 189 patients with post‐traumatic osteomyelitis and 200 healthy controls were enrolled for genotyping using the SNaPshot genotyping method. Statistically significant associations were found between the gene polymorphism and the risk of post‐traumatic osteomyelitis by dominant model (AA + AT vs. TT, OR = 1.820, p = .017) and heterozygous model (AT vs. TT, OR = 1.781, p = .029). Moreover, the frequency of mutant allele A was significantly higher in the patients than that in the healthy controls (15.07% vs. 9.25%, OR = 1.742, p = .013). IFN‐γ +874T/A polymorphism may contribute to the increased susceptibility to post‐traumatic osteomyelitis.     

Associations of HLA class II alleles with pulmonary tuberculosis in Thais

Tuberculosis is an important infectious disease in Thailand. Susceptibility to tuberculosis is influenced not only by the environment but also by host genetic factors. In this study, we investigated HLA alleles in 82 patients with tuberculosis from Bangkok and in 160 normal controls. HLA‐DRB1, DQA1 and DQB1 genotyping was performed by the PCR‐SSO method. The frequency of HLA‐DQB1*0502 was increased in tuberculosis patients compared to the normal controls (P = 0.01, OR = 2.06). In contrast, the frequencies of DQA1*0601 and DQB1*0301 were decreased in tuberculosis patients compared to the controls (P = 0.02 and P = 0.01, respect­ively). Our results suggest that HLA‐DQB1*0502 may be involved in the development of pulmonary tuberculosis, whereas HLA‐DQA1*0601 and DQB1*0301 may be associated with protection against tuberculosis.     

Levels of Interleukin‐(IL)‐12p40 are Markedly Increased in Brucellosis Among Patients with Specific IL‐12B Genotypes

Brucellosis remains a major zoonosis worldwide. Brucella antigens induce the production of T‐helper 1 (Th1) cytokines such as interleukin‐12 (IL‐12) in humans. We aimed to investigate the association of two single nucleotide polymorphisms (SNPs) in the gene encoding the IL‐12p40 cytokine (IL‐12B) with brucellosis and to examine the functionality of these SNPs through measuring serum levels of IL‐12p40. We genotyped IL‐12B gene rs3212227, A>C; rs6887695 G>C polymorphisms in a case‐control study on a total of 281 subjects including 153 patients with active brucellosis and 128 healthy controls, using RFLP and serum IL‐12p40 levels, were assessed by ELISA. The rs3212227 minor allele (C) and homozygote genotype (CC) were more frequent in controls compared with patients with brucellosis (P = 0.006, OR = 0.608, 95%CI = 0.429–0.861 for the C allele; P = 0.024, OR = 0.443, 95% CI: 0.218–0.900 for the CC genotype). Comparison of IL‐12B genotypes and serum levels of the IL‐12p40 revealed that rs3212227 AA genotype, with higher frequency in patients than in controls, was associated with increased levels of the cytokine (P = 0.0001). Furthermore, the distribution of haplotype and genotype combinations in our study suggested that rs3212227C/rs6887695C haplotype or CC/GC or CC/CC genotype combinations may protect controls against Brucella infection by contributing to a functional downregulation of the serum IL‐12p40 production in vivo, as shown by ELISA (P < 0.05). Overall, our study demonstrated that rs3212227 A variant was associated with higher levels of serum IL‐12p40 and could possibly contribute to an inherited predisposition to brucellosis.     

TGFB1 Functional Gene Polymorphisms (C‐509T and T869C) in the Maternal Susceptibility to Pre‐eclampsia in South Indian Women

Pre‐eclampsia (PE), a pregnancy‐specific vascular disorder characterized by hypertension and proteinuria, is hypothesized to be the result of inadequate placental angiogenesis with attendant systemic inflammation. The pleiotropic cytokine, Transforming Growth Factor‐β1 (TGF‐β1), is considered to be a key candidate gene in the molecular pathogenesis of PE by virtue of its ability to not only regulate angiogenesis and apoptosis of target cells, but also by acting as a master controller of Th1/Th2 cytokine balance and production of the anti‐inflammatory peripheral regulatory T cells (FOXP3+ Tregs). Based on this presumption, we screened a total of 469 pregnant women from South India that include 239 patients with PE and 230 healthy controls for the two functional polymorphisms of TGFB1 gene (C‐509T and T869C). The genotype frequencies of these two polymorphisms differed significantly between the PE and control groups (P = 0.01 and P = 0.002, for the TGFB1 C‐509T and T869C polymorphisms, respectively). Under the over‐dominant model, the CT genotype of the TGFB1 C509T polymorphism showed a high protective effect (P = 3e‐04), while the TT genotype of the same variant appeared to be the predisposing genotype (P = 0.003). The T‐T and C‐C haplotypes were found to be the risk haplotypes blocks towards PE (OR = 4.72; P = 0.031, OR = 5.39; P = 0.03), respectively. Strong linkage disequilibrium was seen between the two polymorphisms. Our investigations revealed a significant influence of TGFB1 C‐509T and T869C polymorphisms on the PE risk in South Indian women. The study represents one of the first of its kind from the Indian subcontinent.     

Bleomycin‐induced chromosomal damage and shortening of telomeres in peripheral blood lymphocytes of incident cancer patients

Disruption of genomic integrity due to deficient DNA repair capacity and telomere shortening constitute hallmarks of malignant diseases. Incomplete or deficient repair of DNA double‐strand breaks (DSB) is manifested by chromosomal aberrations and their frequency reflects inter‐individual differences of response to exposure to mutagenic compounds. In this study, we investigated chromosomal integrity in peripheral blood lymphocytes (PBL) from newly diagnosed cancer patients, including 47 breast (BC) and 44 colorectal cancer (CRC) patients and 90 matched healthy controls. Mutagen sensitivity was evaluated by measuring chromatid breaks (CTAs) induced by bleomycin and supplemented by the chemiluminescent measurement of γ‐H2AX phosphorylation in 19 cancer patients (11 BC, 8 CRC). Relative telomere length (RTL) was determined in 22 BC, 32 CRC, and 64 controls. We observed statistically significant increased level of CTAs (P = .03) and increased percentage of aberrant cells (ACs) with CTAs (P = .05) in CRC patients compared with controls after bleomycin treatment. No differences were observed between BC cases and corresponding controls. CRC and BC patients with shorter RTL (below median) exhibited significantly higher amount of ACs (P = .02), CTAs (P = .02), and cells with high frequency of CTAs (≥12 CTAs/PBL; P = .03) after bleomycin treatment. No such associations were observed in healthy controls. γ‐H2AX phosphorylation after bleomycin treatment in PBL did not differ between CRC and BC patients. Our results suggest that altered DSB repair measured by sensitivity towards mutagen in PBL occurs particularly in CRC carcinogenesis. Irrespective of cancer type, telomere shortening may be associated with a decreased capacity to repair DSB.     

The association of CTLA‐4 and CD28 gene polymorphisms with idiopathic ischemic stroke in the paediatric population

Autoimmune vasculitis is believed to be a critical factor in the development of idiopathic childhood ischemic stroke. The association of polymorphisms in CTLA‐4 and CD28 with some immune vasculitides, such as systemic lupus erythematosus (SLE) and Behçet's disease has been reported. The aim of the present study is to investigate the association of the genetic variants in the CTLA‐4 and CD28 genes of children who suffered idiopathic ischemic stroke using a case–control design. Two single nucleotide polymorphisms (SNPs) in the CTLA‐4 gene and an SNP in the CD28 gene were genotyped in 51 patients who suffered idiopathic ischemic stroke, and in 74 healthy controls from mainland China. An SNP, CTLA‐4+49A/G located in exon 1 of the CTLA‐4 gene, showed nominal association with the disease (P = 0.012, odds ratio (OR) = 2.09, 95% confidence interval (CI) = 1.17–3.73) using allele‐based analysis. Homozygous carriers of the G allele of this SNP were more common in the patients than in the controls (P = 0.008). The CD28IVS3 +17TT genotype was found to be more common in the patients than in the controls (P = 0.039, OR = 2.96, 95% CI = 1.02–8.58). No correlations of at‐risk genotype (G/G) of CTLA‐4+49A/G and genotype (T/T) of CD28+17T/C with the main clinical features of idiopathic childhood ischemic stroke were observed. The results suggest that polymorphisms in the CTLA‐4 and CD28 genes may contribute to the increased risk of idiopathic ischemic stroke.     

Errors in 1H‐MRS estimates of brain metabolite concentrations caused by failing to take into account tissue‐specific signal relaxation

Accurate measurement of brain metabolite concentrations with proton magnetic resonance spectroscopy (¹H‐MRS) can be problematic because of large voxels with mixed tissue composition, requiring adjustment for differing relaxation rates in each tissue if absolute concentration estimates are desired. Adjusting for tissue‐specific metabolite signal relaxation, however, also requires a knowledge of the relative concentrations of the metabolite in gray (GM) and white (WM) matter, which are not known a priori. Expressions for the estimation of the molality and molarity of brain metabolites with ¹H‐MRS are extended to account for tissue‐specific relaxation of the metabolite signals and examined under different assumptions with simulated and real data. Although the modified equations have two unknowns, and hence are unsolvable explicitly, they are nonetheless useful for the estimation of the effect of tissue‐specific metabolite relaxation rates on concentration estimates under a range of assumptions and experimental parameters using simulated and real data. In simulated data using reported GM and WM T₁ and T₂ times for N‐acetylaspartate (NAA) at 3 T and a hypothetical GM/WM NAA ratio, errors of 6.5–7.8% in concentrations resulted when TR = 1.5 s and TE = 0.144 s, but were reduced to less than 0.5% when TR = 6 s and TE = 0.006 s. In real data obtained at TR/TE = 1.5 s/0.04 s, the difference in the results (4%) was similar to that obtained with simulated data when assuming tissue‐specific relaxation times rather than GM–WM‐averaged times. Using the expressions introduced in this article, these results can be extrapolated to any metabolite or set of assumptions regarding tissue‐specific relaxation. Furthermore, although serving to bound the problem, this work underscores the challenge of correcting for relaxation effects, given that relaxation times are generally not known and impractical to measure in most studies. To minimize such effects, the data should be acquired with pulse sequence parameters that minimize the effect of signal relaxation.     

Partial volume mapping using magnetic resonance fingerprinting

Magnetic resonance fingerprinting (MRF) is a quantitative imaging technique that maps multiple tissue properties through pseudorandom signal excitation and dictionary‐based reconstruction. The aim of this study is to estimate and validate partial volumes from MRF signal evolutions (PV‐MRF), and to characterize possible sources of error. Partial volume model inversion (pseudoinverse) and dictionary‐matching approaches to calculate brain tissue fractions (cerebrospinal fluid, gray matter, white matter) were compared in a numerical phantom and seven healthy subjects scanned at 3 T. Results were validated by comparison with ground truth in simulations and ROI analysis in vivo. Simulations investigated tissue fraction errors arising from noise, undersampling artifacts, and model errors. An expanded partial volume model was investigated in a brain tumor patient. PV‐MRF with dictionary matching is robust to noise, and estimated tissue fractions are sensitive to model errors. A 6% error in pure tissue T₁ resulted in average absolute tissue fraction error of 4% or less. A partial volume model within these accuracy limits could be semi‐automatically constructed in vivo using k‐means clustering of MRF‐mapped relaxation times. Dictionary‐based PV‐MRF robustly identifies pure white matter, gray matter and cerebrospinal fluid, and partial volumes in subcortical structures. PV‐MRF could also estimate partial volumes of solid tumor and peritumoral edema. We conclude that PV‐MRF can attribute subtle changes in relaxation times to altered tissue composition, allowing for quantification of specific tissues which occupy a fraction of a voxel.     

Cytokine gene polymorphisms and breast cancer susceptibility and prognosis*

Single nucleotide polymorphisms (SNPs) in the promoter regions of cytokine genes are associated with differential levels of cytokine expression. We hypothesized that these SNPs might influence breast tumour development and progression by affecting the efficiency of the antitumour immune response and/or pathways of angiogenesis. A total of 144 female breast cancer patients and 263 cancer‐free population controls were genotyped for the interleukin (IL)‐1β?511 (T/C), IL‐6 ?174 (G/C), tumour necrosis factor (TNF)‐α?308 (A/G), IL‐10 ?1082 (A/G), IL‐8 ?251 (A/T) and vascular endothelial growth factor (VEGF) ?1154 (A/G) SNPs, using amplification refractory mutation system polymerase chain reaction (ARMS‐PCR) and TaqMan® (Applied Biosystems, Foster City, CA, USA) 5′ nuclease assays for allelic discrimination. No significant associations were seen. Patient–control comparisons revealed a non‐significant trend for association between the TNF‐α?308 GG genotype and breast cancer compared to controls (79.7 vs. 68.2%, P = 0.03, P_c = 0.54). Stratification of the patient group according to the Nottingham Prognostic Index and individual prognostic factors revealed trends for association between IL‐6 ?174 GC and IL‐8 ?251 AA genotypes and markers of poor prognosis (P = 0.04, P_c = 0.72 and P = 0.02, P_c = 0.36, respectively). There were also trends for associations between VEGF ?1154 AG and IL‐1β?511 TC genotypes and markers of good prognosis (P = 0.02, P_c = 0.36 and P = 0.05, P_c = 0.90, respectively). These results suggest that the role of cytokine promoter SNPs in both susceptibility to and prognosis in breast cancer requires further investigation in a larger study.     

Genetic analysis of the interleukin‐1 receptor antagonist and its homologue IL‐1L1 in alopecia areata: strong severity association and possible gene interaction‡

Alopecia areata is an inflammatory hair loss disease with a major genetic component. The presence of focal inflammatory lesions with perifollicular T‐cell infiltrates reflects the importance of local cytokine production in the pathogenesis. In addition to its fundamental pro‐inflammatory role, the interleukin‐1 (IL‐1) system has major effects on hair growth regulation in vitro, with the inhibitory actions of IL‐1α and IL‐1β being opposed by the receptor antagonist IL‐1ra. The novel interleukin‐1 like molecule 1 (IL‐1L1) which has greatest gene sequence homology with IL1RN, the gene encoding IL‐1ra, is another potential IL‐1 antagonist. In view of previous studies suggesting a significant role for IL1RN polymorphisms in the pathogenesis of autoimmune/inflammatory disease, we have analysed polymorphisms of IL‐1ra (IL1RN+2018) and its homologue IL‐1L1 (IL1L1+4734) in a case–control association study on 165 patients and a large number of matched controls. Homozygosity for the rare allele of IL1RN (IL1RN*2) was significantly associated with alopecia areata [odds ratio (OR) = 1.89, 95% CI (1.09, 3.28); P = 0.02], confirming our previous findings of significant association with the IL1RN variable number tandem repeat (VNTR). The results also revealed a novel association involving a polymorphism of the interleukin‐1 receptor antagonist homologue IL1L1 at position + 4734, IL1RN+2018, and alopecia areata. The effect of a genotype combining three copies of the rare alleles at the IL1RN and IL1L1 loci conferred a more than additive increase in the risk of disease compared to IL1RN+2018 or IL1L1+4734 alone [OR 3.37 (1.60, 7.06); P = 0.002], suggesting possible synergy between the IL1RN and IL1L1 genes. This effect was stronger in patients with severe disease (alopecia totalis/universalis) [OR 4.62 (1.87, 11.40), P = 0.0022], and in those with early age at onset (< 20 years) [OR = 6.38 (2.64, 15.42), P = 0.0002]. Our results suggest that these polymorphisms within IL1RN and IL1L1 themselves or a gene in linkage disequilibrium with IL1RN and IL1L1 predispose to the more severe forms of alopecia areata.     

Haplotype analysis of HLA‐A, ‐B antigens and ‐DRB1 alleles in south Indian HIV‐1‐infected patients with and without pulmonary tuberculosis

We have shown earlier the association of human leucocyte antigen (HLA)‐A11 with resistance and HLA‐B40 and ‐DR2 with susceptibility to HIV and HIV‐TB. In the present study, we have attempted to find out the HLA‐DR2 subtypes and the possible HLA‐A/‐B/‐DRB1 haplotype combinations that are associated with susceptibility or resistance to HIV and HIV with pulmonary tuberculosis (HIV+PTB+). HLA‐DR2 subtyping was carried out by polymerase chain reaction‐based sequence‐specific oligonucleotide probe method. Overrepresentation of HLA‐DRB1*1501 in HIV‐positive PTB‐negative (HIV+PTB–) patients (P = 0.004, P_c = 0.06) and ‐DRB1*1502 in HIV‐positive PTB‐positive (HIV+PTB+) patients (P = 0.019) was observed as compared to healthy controls. Haplotype analysis revealed an increased frequency of HLA‐A2‐DRB1*1501 haplotype in HIV+PTB– patients (P = 0.008) and HLA‐A2‐DRB1*1502 among HIV+PTB+ patients (P = 0.01) compared to healthy controls. The haplotypes B40‐DRB1*1501 and B40‐DRB1*04 were found to be moderately increased in HIV+PTB– and HIV+PTB+ patients (P < 0.05). The study suggests that HLA‐A2‐DRB1*1501 haplotype may be associated with HIV infection while HLA‐A2‐DRB1*1502 haplotype might be associated with susceptibility to PTB in HIV patients. Moreover, HLA‐B40‐DRB1*1501 and HLA‐B40‐DRB1*04 haplotypes may be associated with susceptibility to HIV infection and to PTB in HIV patients.     

Association of IL‐1β +3954 C/T and IL‐10‐1082 G/A Cytokine Gene Polymorphisms with Susceptibility to Tuberculosis

Tuberculosis (TB) constitutes the major cause of death due to infectious diseases. Cytokines play a major role in defence against Mycobacterium tuberculosis infection. Polymorphisms in the genes encoding various cytokines have been associated with tuberculosis susceptibility. Household contacts (HHC) are at increased risk of developing the disease. In this study, we examined the association of IL‐1β and IL‐10 cytokine gene polymorphisms with risk of developing tuberculosis in TB patients, their HHC and healthy controls (HC) using JavaStat and SPSS. Multifactor dimensionality reduction (MDR) analyses were performed to explore the potential gene–gene interactions. The genotype and allele frequencies of IL‐1β +3954C/T polymorphism did not vary significantly between TB patients and HC. GG (P < 0.005, OR = 0.219 and 95% CI = 0.059–0.735) and GA (P < 0.0001, OR = 2.938 and 95% CI = 1.526–5.696) genotypes of IL‐10‐1082 G/A polymorphism were found to be significantly associated with patients versus HC. HHC with CC (P < 0.03, OR = 1.833 and 95% CI = 1.1–3.35) genotype in IL‐1β and GA (P < 0.0001, OR = 4.612 and 95% CI = 2.225–9.702) genotype in IL‐10 were at increased risk of developing tuberculosis. MDR tests revealed high‐risk genotypes in IL‐1β and IL‐10 based on the association model. Our results demonstrate that the polymorphisms of IL‐1β and IL‐10 genes may be valuable markers to predict the risk for the development of TB in household contacts.     

Preclinical MR fingerprinting (MRF) at 7 T: effective quantitative imaging for rodent disease models

High‐field preclinical MRI scanners are now commonly used to quantitatively assess disease status and the efficacy of novel therapies in a wide variety of rodent models. Unfortunately, conventional MRI methods are highly susceptible to respiratory and cardiac motion artifacts resulting in potentially inaccurate and misleading data. We have developed an initial preclinical 7.0‐T MRI implementation of the highly novel MR fingerprinting (MRF) methodology which has been described previously for clinical imaging applications. The MRF technology combines a priori variation in the MRI acquisition parameters with dictionary‐based matching of acquired signal evolution profiles to simultaneously generate quantitative maps of T₁ and T₂ relaxation times and proton density. This preclinical MRF acquisition was constructed from a fast imaging with steady‐state free precession (FISP) MRI pulse sequence to acquire 600 MRF images with both evolving T₁ and T₂ weighting in approximately 30 min. This initial high‐field preclinical MRF investigation demonstrated reproducible and differentiated estimates of in vitro phantoms with different relaxation times. In vivo preclinical MRF results in mouse kidneys and brain tumor models demonstrated an inherent resistance to respiratory motion artifacts as well as sensitivity to known pathology. These results suggest that MRF methodology may offer the opportunity for the quantification of numerous MRI parameters for a wide variety of preclinical imaging applications. Copyright © 2015 John Wiley & Sons, Ltd.     

CTLA‐4 gene polymorphism of exon 1(+49 A/G) in Turkish systemic lupus erythematosus patients

Cytotoxic T lymphocyte‐associated antigen‐4 is a cell‐surface molecule providing a negative signal for T cell activation. CTLA‐4 gene polymorphisms are known to be related with genetic susceptibility to various autoimmune diseases, including systemic lupus erythematosus (SLE). However, the effects of this polymorphism on clinical features of SLE have not been defined. We analysed the CTLA‐4 gene +49 A/G polymorphisms in patients with SLE by using polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) and investigated the effect of polymorphisms on clinical outcomes. Blood was collected from 47 unrelated Turkish SLE patients, all fulfilling the American College of Rheumatology criteria for SLE, and 100 ethnically matched healthy volunteers. The AA genotype was a predominant genotype in the Turkish population and genotype frequencies of CTLA‐4 AA were significantly higher in SLE patients (70%) than healthy controls (47%) (P = 0.015). There was a statistically significant difference in the AA genotype [odds ratio (OR): 2.66, confidence interval (CI) 95%: 1.27–5.56, P = 0.014] distribution among patients and controls. There was also an increase in A allele frequency in SLE and controls, but the difference was not statistically significant (81% vs. 70%, P = 0.068, OR = 1.8, CI 95%: 0.99–3.28). Interestingly, mean age and mean age of onset disease was higher in AA homozygote SLE patients compared to non‐AA (39.2 ± 11.5 vs. 31.6 ± 10.6, P = 0.044; 32.38 vs. 24.31, P = 0.046, respectively). There was no association between genotype and the other clinical features of SLE. Our results suggested that CTLA‐4 +49 AA genotype might be a risk factor for the development of SLE in Turkish population and G allele might be involved in early development of SLE. No association with clinical features was found for polymorphism of the promoter region in CTLA‐4 +49.     

Association of PTPN22+1858C/T polymorphism with Type 1 diabetes in the North Indian population

A nonsynonymous SNP +1858C/T (rs2476601) in the protein tyrosine phosphatase, nonreceptor type 22(PTPN22) gene leading to Arg 620 Trp substitution is known to be associated with susceptibility to type 1 diabetes (T1D) and several other autoimmune diseases. We studied this polymorphism in 145 T1D patients and 210 healthy controls from North India. The minor allele +1858T was observed to be significantly increased among patients as compared to healthy controls (2.76% vs 0.5%, P = 0.027, OR = 5.93; 95% CI = 1.4–24.8). The association was also observed at the level of heterozygous C/T genotype (5.5% vs 0.95%, P = 0.026, OR = 6.07; 95% CI = 1.43–25.6). The T allele and C/T genotype were predominantly found among patients who were positive for both glutamic acid decarboxylase 65 (GAD65) and insulin antigen 2 (IA2) autoantibodies and showed significantly increased frequencies (10%, P = 0.034, OR = 11.67; 95% CI = 1.58–84.1 and 20%, P = 0.031, OR = 13.0; 95% CI = 1.66–97.5, respectively) as compared to patients negative for these autoantibodies (0.95% and 1.9%, respectively). The results suggest that the PTPN22+1858T allele is positively associated with T1D in the North Indian population.     

Association of cytokine Th2 gene polymorphisms with autoimmune thyroid diseases in Tunisian population

Autoimmune thyroid diseases (AITD) including Graves' disease (GD) and Hashimoto's thyroiditis (HT) are complex genetic diseases. Th2 cytokines act on the development of AITD. This study was conducted on Tunisian patients with AITD to investigate the association of Th2 cytokine gene polymorphisms and haplotype combination with GD or HT risk. A total of 156 controls, 160 patients with HT and 88 patients with GD were genotyped for IL‐4 rs2243250, IL‐5 rs2069812, IL‐6 rs1800796 and IL‐13 rs1800925 polymorphisms by PCR‐RFLP. The AITD risk was assessed by a logistic regression analysis using the SNP stats statistical program. False‐positive report probability (FPRP) was estimated to evaluate significant findings. IL‐13 rs1800925 was associated with GD, after adjustment for age and gender, in codominant, dominant and allele genetic models (p = .0072; p = .0018; p = .012, respectively). Significant association of the IL‐6 rs1800796C/G genotype with GD was also detected (p = .025). Furthermore, increased risk of HT was still found for IL‐13 rs1800925T allele (p = .039, OR = 1.39) and for IL‐4 rs2243250T/T genotype both in codominant (p = .033, OR = 2.59) and recessive (p = .011, OR = 2.73) models after adjustment for age and gender. Interestingly, haplotype analysis performed on the IL‐4, IL‐5 and IL‐13 genes revealed a high risk of HT with CTT haplotype (p = .008, OR = 2.12). However, the CCT haplotype is a protective factor (OR = 0.36). Patients carrying the CT haplotype with only one minor allele had a moderate risk of HT (OR = 1.56). The FPRP analysis showed that the association of IL‐13 rs1800925 polymorphism with GD and HT and the association of CTT haplotype with HT were noteworthy. In conclusion, the IL‐4, IL‐5, IL‐6 and IL‐13 polymorphism may play a role in susceptibility to GD and HT in the Tunisian population. Furthermore, gene–gene interaction between the IL‐4, IL‐5 and IL‐13 significantly increases the risk of AITD. Further studies with larger numbers of individuals are needed to confirm the results.     

Frequency and Expression of Inhibitory Markers of CD4+CD25+FOXP3+ Regulatory T Cells in Patients with Common Variable Immunodeficiency

Common variable immunodeficiency (CVID) is the most symptomatic primary antibody deficiency associated with recurrent infections and chronic inflammatory diseases as well as autoimmunity. CD4⁺CD25⁺FOXP3⁺ regulatory T cells (Tregs) are critical T cell subsets for maintaining self‐tolerance and regulation of immune response to antigens thus play a pivotal role in preventing autoimmunity. Thirty‐seven CVID patients and 18 age‐/sex‐matched controls were enrolled. Peripheral blood mononuclear cells (PBMCs) were obtained from both groups, and the percentage of Tregs was calculated using flow cytometry method. The mRNA expression of Tregs' surface markers cytotoxic T lymphocyte–associated antigen‐4 (CTLA‐4) and glucocorticoid‐induced tumour necrosis factor receptor (GITR), which are associated with Tregs' inhibitory function, was compared between patients and controls by quantitative real‐time PCR TaqMan method. The results revealed that the frequency of Tregs was significantly lower in CVID patients than normal individuals (P < 0.001). In addition, CVID patients with autoimmunity were found to have markedly reduced proportion of Tregs compared to those cases without autoimmune diseases (P = 0.023). A significant difference was seen in factor forkhead box P3 (FOXP3) expression between CVID patients and controls (P < 0.001). The mRNAs of CTLA‐4 and GITR genes were expressed at lower levels in CVID patients compared to control group (P = 0.005 and <0.001, respectively). Our findings showed reduced proportion of Tregs in CVID patients together with downregulation of FOXP3 protein and diminished expression of inhibitory Tregs' markers. It could be concluded that all of these changes may be responsible for cellular immune dysregulation observed in these patients especially those with autoimmune manifestation.