Genetic Polymorphisms of Cytotoxic T-Lymphocyte Antigen 4 in Primary Biliary Cholangitis: A Meta-Analysis

Soluble immune checkpoints are elevated in patients with primary biliary cholangitis

BACKGROUND

Primary biliary cholangitis (PBC) is a chronically progressive liver disease mediated by an autoimmune response. The aetiology and pathogenesis of PBC are not fully understood and may be related to immune disorders caused by genetic factors and their interaction with environmental factors. Immune checkpoints play an important role in preventing the occurrence of autoimmunity. However, the level of immune checkpoints in PBC has not been reported. Here, we aimed to identify the serum levels of soluble checkpoints in patients with PBC.

METHODS

Soluble checkpoint levels were evaluated using enzyme-linked immunosorbent assay in 60 patients with PBC and 20 healthy controls (HCs). The expression of immune checkpoints was compared in liver biopsy tissue samples using immunohistochemistry. Receiver operating characteristic (ROC) curves and area under the curve (AUCs) were used to determine the diagnostic performance of soluble checkpoints and laboratory indexes between patients with PBC and HCs and patients with mild and advanced PBC. A logistic regression was performed for advanced PBC.

RESULTS

sCD134, sLAG-3, sPD-1, sPD-L1, and sTIM-3 levels were significantly increased in patients with PBC compared with those in healthy controls. Additionally, the levels of sCD134, sPD-1, sPD-L1, and sTIM-3 were positively associated with disease progression. Moreover, soluble checkpoints were correlated with immunoglobulin and liver functions. ROC analyses between patients with PBC and HCs showed that the AUCs of sOX40, sPD-1, and sPD-L1 were 0.967, 0.922, and 0.971, respectively. The optimal cut-off values of sOX40, sPD-1, and sPD-L1 for PBC diagnosis were 89.15, 213.4, and 68, respectively. ROC analyses between mild and advanced patients with PBC revealed that the AUCs of sOX40 and sTIM-3 were 0.767 and 0.765, respectively. The optimal cut-off values for predicting PBC stage ≥ III were 199.45 and 361.5, respectively. In univariate analysis, age, ALB, and sOX40 were associated with advanced PBC. Further, the expression of CD134 and TIM-3 was upregulated in the liver of patients with PBC.

CONCLUSIONS

Our study results indicate that the serum titer of soluble checkpoints is increased in Chinese patients with PBC.

The TNF-α rs361525 and IFN-γ rs2430561 polymorphisms are associated with liver cirrhosis risk: a comprehensive meta-analysis

Background

Inflammation serves as an essential driver of liver cirrhosis (LC) incidence. Accordingly, a meta-analysis was carried out to explore the association between specific polymorphisms in the interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) genes and the incidence of LC based on comparisons of genotype and allele frequencies.

Objectives

To study the relationship between TNF-α rs361525 and IFN-γ rs2430561 polymorphisms and the risk of LC.

Methods

A database search was performed for all studies published as of September 10, 2022. The strength of risk relationships was assessed based on odds ratios (ORs) with 95% confidence intervals (CIs).

Results

Pooled analyses were conducted for one common TNF-α polymorphism (rs361525) as well as one common IFN-γ polymorphism (rs2430561). Both of these SNPs were identified as LC-related risk factors. Specifically, rs361525 was related to LC incidence in both alcoholic liver cirrhosis (OR: 1.86, 95%CI: 1.03-3.34) and hepatitis B virus (HBV)-related cirrhosis cases (OR: 1.44, 95%CI: 1.00-2.06) when using an allelic contrast model. Moreover, rs2430561 was significantly related to LC in an Asian population (OR: 1.45, 95%CI: 1.13-1.86) and in the context of HBV-related cirrhosis (OR: 1.48, 95%CI: 1.13-1.93) when using an allelic contrast model.

Conclusion

These findings indicate that rs361525 and rs2430561 represent LC-related risk factors, although additional large-scale clinical and case-control studies will be vital to confirm these results.

Autoimmune pancreatitis: What we know so far

Autoimmune pancreatitis (AIP) is a rare, often‐missed disease that involves inflammation of the pancreas and strictures of the pancreatic duct. Its prevalence and incidence in the United States remain scarce. The disease has a varied presentation and often mimics pancreatic malignancy, which can make the diagnosis challenging. Most patients have an excellent response to corticosteroid therapy. Immunomodulators may be used in some cases. Rituximab is an effective, emerging treatment in steroid‐refractory cases. This study aims to review the two distinct types of AIP and provide a detailed analysis of the diagnostic approach and treatment modalities.

Impact of cytotoxic T-lymphocyte-associated protein 4 codon 17 variant and expression on vitiligo risk

BACKGROUND

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is one of the essential brakes expressed on T cells that prevent T-cell hyperactivation-associated autoimmune disorders. Several CTLA4 polymorphisms were implicated in the regulation of gene expression. We aimed to explore the association of CTLA4 expression and rs231775 (c.49A>G) variant with vitiligo risk and severity of the disease in a sample of the Middle Eastern population.

METHODS

The CTLA4 gene expression and genotyping for rs231775 (A/G) variant were assessed in 161 vitiligo patients and 165 controls using a real-time polymerase chain reaction. Vitiligo Area Severity Index (VASI) and Vitiligo Disease Activity score (VIDA) were evaluated.

RESULTS

A higher frequency of rs231775 G allele was observed in vitiligo cases than controls (45% vs. 33%, p = 0.002). After adjustment of age, sex, family history of vitiligo, and CTLA expression level, using multivariate analysis, G/G carriers were associated with a higher risk of vitiligo under recessive (OR = 2.94, 95% CI = 1.61-5.35, p < 0.001), dominant (OR = 1.87, 95% CI = 1.14-3.06, p = 0.013), and homozygote comparison (OR = 3.34, 95% CI = 1.73-6.42, p = 0.001) models. Although the CTLA4 relative expression levels were comparable to that of controls, G/G carriers exhibited a significantly lower expression profile (median = 0.63, IQR = 0.34-1.75) than A/A (median = 1.43, IQR = 0.39-4.25, p = 0.018) and A/G carriers (median = 1.68, IQR = 0.49-3.92, p = 0.007). No significant associations of CTLA4 variant/expression with disease severity and/or activity were observed.

CONCLUSION

The CTLA4 rs231775 variant was associated with vitiligo susceptibility and gene expression; the risky genotype (GG) was associated with lower CTLA4 relative expression levels than the other genotypes. Further large-scale studies in different populations are warranted.

Cytotoxic T lymphocyte antigen-4 gene polymorphisms and susceptibility to type 1 autoimmune hepatitis in the Tunisian population

Genetic factors and gene polymorphisms leading to the onset of autoimmune response in autoimmune hepatitis (AIH) are still not full elucidated. Since the CTLA-4 molecule is a key modulator of the lymphocytes responses we hypothezied that deficiencies or mutations in the gene encoding CTLA4 protein may be involved in AIH susceptibility and trigger the autoimmune response. We investigated 3 distinct polymorphic sites (+49A > G, CT60 G > A and -318C > T) of the CTLA4 gene in 50 AIH patients and 100 healthy controls using the KASP genotyping technology. A significant positive association with AIH susceptibility was found for the GG genotype in +49 position of the CTLA4 gene which was significantly higher in AIH patients compared to controls (28% vs 9%, p = 0.003, OR = 3.93 [1.56-9.88]). The CTLA4 A/A genotype in position CT60 was more significantly frequent in controls comparing to AIH patients and could be considered as a protective genotype for the tunisian patients. CTLA4 genotyping in position -318 did not show any statistically significant difference in genotype or allele distribution. The CTLA4 gene polymorphism in position +49 is associated to AIH susceptibility in the Tunisian population. Mutation in the CTLA4 gene may lead to a modification of the CTLA4 protein structure that could have functional relevance in AIH pathogenesis and onset.