Tumor necrosis factor-alpha promoter polymorphisms and the risk of rejection after liver transplantation: a case control analysis of 210 donor-recipient pairs

Association Between Interleukin-2 -330 T/G Polymorphism and Acute Renal Graft Rejection: A Meta-analysis

BACKGROUND

Interleukin-2 (IL-2) -330 T/G promoter polymorphism is involved in the acute rejection (AR) risk of kidney transplantation. However, results from published studies on the association between recipient IL-2-330 T/G polymorphism and AR risk are conflicting and inconclusive.

METHODS

We searched Medline, Embase, Web of Science, and Cochrane Central Register from their inceptions through January 2015 for relevant studies. Data concerning publication information, population characteristics, and transplant information were extracted. Odds ratios (ORs) were calculated for the association between IL-2-330 T/G polymorphism and AR risk.

RESULTS

This meta-analysis included 8 case-control studies with 1,405 cases of renal transplant recipients. The pooled estimate showed that IL-2-330 T/G polymorphism was not associated with AR risk: TT vs TG+GG: OR(fixed,) 0.93; 95% confidence interval [CI], 0.72-1.21; P = .60; GG vs TG+TT: OR(fixed), 1.15; 95% CI, 0.76-1.72; P = .51; TG vs TT+GG: OR(fixed), 1.01; 95% CI, 0.78-1.31; P = .91; T vs G: OR(fixed), 0.93; 95% CI, 0.77-1.13; P = .48. None of subgroup analyses yielded significant results in the association between IL-2-330 T/G polymorphism and AR risk. Meta-regression confirmed that there was no significant correlation between the preselected trial characteristics and our study results.

CONCLUSIONS

This meta-analysis suggests that IL-2-330 T/G polymorphism may not be associated with AR risk in renal transplant recipients.

Association of interleukin4 gene polymorphisms of recipients and donors with acute rejection following living donor liver transplantation

BACKGROUND

Little is known as to whether the interleukin4 (IL4) gene polymorphisms in recipients or donors affect the incidence of acute cellular rejection (ACR) following living donor liver transplantation (LDLT). Therefore, we determined the effect of IL4 T-33C polymorphisms in recipients and donors on ACR in a large cohort of patients that underwent LDLT.

METHODS

We examined 155 LDLT cases treated at Nagoya University or Kyoto University, Japan, between 2004 and 2009. IL4 T-33C polymorphisms were analyzed in recipients and donors.

RESULTS

Forty-seven recipients (30.3%) developed early ACR. The genotype frequency of IL4 T-33C in the recipients was associated with ACR incidence (P=0.008, P<0.0125 considered significant). Patients with the IL4-33C carrier genotype (C/C or C/T) were significantly associated with a higher incidence of ACR relative to those with the T/T genotype (OR=3.27, 95% CI: 1.56-6.88, P=0.002). The genotype frequencies of IL4 T-33C in the donors were not associated with rejection incidence. In addition, there was no significant effect of IL4 T-33C genotype combinations on ACR incidence in donors and recipients.

CONCLUSIONS

Genotyping of IL4 T-33C in recipients might be useful to stratify the liver transplant recipients according to their risk of ACR.

Interleukin-10-1082 G/a polymorphism and acute renal graft rejection: a meta-analysis

OBJECTIVE

The aim of this study was to investigate the association between interleukin (IL)-10-1082 (G/A) promoter polymorphism and acute rejection (AR) in renal transplant recipients.

METHODS

We searched MEDLINE, EMBASE, Web of Science, and Cochrane Central Register from the inception to March 2015 for relevant studies. Data concerning publication information, population characteristics, and transplant information were extracted. Odds ratios (ORs) was calculated for the association between IL-10-1082 GG genotype (or IL-10-1082 G allele) and AR risk.

RESULTS

This meta-analysis included 22 case-control studies including 2779 cases of renal transplant recipients. The pooled estimate showed that the IL-10-1082 GG genotype was not significantly associated with AR risk (ORrandom=1.07, 95% CI 0.80-1.43, p = 0.64). Similarly, the pooled estimate showed that the IL-10-1082 G allele was not significantly associated with AR risk (ORfixed=1.02, 95% CI 0.90-1.16, p = 0.74). None of subgroup analyses yielded significant results in the association between IL-10-1082 GG genotype (or IL-10-1082 G allele) and AR risk. Meta-regression confirmed that there was no significant correlation between the pre-selected trial characteristics and our study results.

CONCLUSIONS

This meta-analysis suggests that IL-10-1082 G/A polymorphism is not significantly associated with AR risk in renal transplant recipients.

Impact of glutathione S-transferase T1 gene polymorphisms on acute cellular rejection in living donor liver transplantation

It has previously been demonstrated that glutathione S-transferase T1 (GSTT1) genetic mismatch between recipient and donor is a risk factor for developing immune-mediated hepatitis following liver transplantation and for antibody-mediated rejection in renal transplantation. Little is known whether the GSTT1 gene polymorphism affects the incidence of acute cellular rejection (ACR) following living donor liver transplantation (LDLT). Patients underwent LDLT at Nagoya University or Kyoto University, Japan, between 2004 and 2009. Genotyping of GSTT1 genes (null or present genotype) was conducted in recipients and donors. A total of 155 LDLT cases were examined. Forty-seven recipients (30.3%) developed early ACR. There was no association of recipient GSTT1 genotype with ACR incidence. However, ACR incidence was significantly higher in recipients transplanted from GSTT1 present genotype donors than in those transplanted from GSTT1 null genotype donors [odds ratio (OR)=2.64, 95% confidence interval (CI)=1.12-5.83, p=0.016]. Moreover, GSTT1 recipient/donor genotype mismatch (present/null or null/present) was significantly associated with ACR development (OR=2.28, 95% CI=1.12-4.61, p=0.022). The genotyping of GSTT1 in recipients and donors might be useful to stratify the liver transplant recipients according to risk of ACR.

The association between cytokine gene polymorphisms and graft rejection in liver transplantation: a systematic review and meta-analysis

We investigated the contribution of polymorphisms in cytokine genes (TNFa-308, IL10-1082 and -592, TGFb1-c10 and c25, and IFNg+874) on the risk of graft rejection in liver transplantation. We performed a systematic review by identifying relevant studies and applied meta-analysis to pool gene effects. In total, 12 studies were eligible and included in the study. Data extraction and assessments for risk of bias were independently performed by two reviewers. Data for allele frequencies, allelic, and genotypic effects were pooled. Heterogeneity and publication bias were assessed. Pooled minor allele frequencies for TNFa-308, IL10-1082, TGFb1-c10, TGFb1-c25, IFNg+874, and IL10-592 were 0.140 (95% CI: 0.083, 0.198), 0.432 (95% CI: 0.392, 0.472), 0.387 (95% CI: 0.307, 0.467), 0.090 (95% CI: 0.056, 0.123), 0.460 (95% CI: 0.392, 0.528), and 0.224 (95% CI: 0.178, 0.269), respectively. OnlyTNFa-308 and IL10-1082 polymorphisms were significantly associated with graft rejection. Patients who carried minor homozygous genotypes for these two polymorphisms were at 3.5 and 1.69 times higher risk of graft rejections than patients who carried major homozygous genotypes. The estimated lambdas were 0.41 and 0.47, suggesting an additive mode of effect was most likely. However, we could not detect the associations of TGFb1at c10 and c25, INFg+874, and IL10-592 polymorphisms and graft rejection. In summary, our systematic review has demonstrated that TNFa-308 and IL10-1082 are potential risk factors of poor outcomes in liver transplantation. Future updated meta-analysis studies to confirm the power of these genotypes in association with allograft rejection are needed.

Interleukin-10-1082G/A polymorphism and acute liver graft rejection: A meta-analysis

AIM: To investigate the association between interleukin (IL)-10-1082 (G/A) promoter polymorphism and acute rejection (AR) in liver transplant (LT) recipients.

METHODS: Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure, and Chinese Biomedicine Databases. Summary odds ratios (ORs) and 95% CIs for IL-10-1082 G/A polymorphism and AR were calculated in a fixed- and a random-effects model as appropriate.

RESULTS: This meta-analysis included seven case-control studies, which comprised 652 cases of LT recipients in which 241 cases developed AR and 411 cases did not develop AR. Overall, the variant A allele was not associated with AR risk when compared with the wild-type G allele (OR = 0.94, 95% CI: 0.64-1.39). Moreover, similar results were observed when the AA genotype was compared with the AG/GG genotype (OR = 1.05, 95% CI: 0.55-2.02). When stratifying for ethnicity, no significant association was observed among either Caucasians or Asians. Because only one study was performed in Asian patients, the result of subgroup analysis by ethnicity would not be reliable for Asians. Limiting the analysis to the studies with controls in the Hardy-Weinberg equilibrium, the results were persistent and robust. No publication bias was found in the present study.

CONCLUSION: This meta-analysis suggests that IL-10-1082 G/A polymorphism may be not associated with AR risk in LT recipients among Caucasians.

Genomic variants associated with primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is an autoimmune hepatobiliary disease characterized by immune-mediated injury of small and medium-sized bile ducts, eventually leading to liver cirrhosis. Several studies have addressed PBC immunopathology, and the data support an immune activation leading to autoantibodies and autoreactive T cells acting against the lipoylated 2-oxoacid dehydrogenase complexes. The causes of the disease remain unknown, but environmental factors and genetic susceptibility both contribute to its onset. Over the past two decades several association studies have addressed the role of genetic polymorphisms in PBC pathogenesis and have reported multiple associations. However, only a few studies had sufficient statistical power, and in most cases results were not independently validated. A genome-wide association study has recently been reported, but this too awaits independent confirmation. The aim of this present work is to critically review the numerous studies dedicated to revealing genetic associations in PBC, and to predict the potential for future studies based on these data.

Allograft TNFbeta and IL16 polymorphisms influence HCV recurrence and severity after liver transplantation

Hepatitis C (HCV) recurrence after liver transplantation is universal although severity varies. We explored whether certain donor cytokine gene polymorphisms may be useful markers of susceptibility to severe recurrence. Allograft tumor necrosis factor (TNF) beta and interleukin (IL) 16 gene polymorphisms were correlated with l-yr clinical outcome among HCV+ recipients. Recipients of donor TNFbeta(2,2) (n = 8) experienced less recurrence (50% vs. 71%, P < 0.05), less fibrosis (25% vs. 76%, P < 0.01), and less rejection (25% vs. 71%, P < 0.01) than donor TNFbeta(1,1) (n = 19). Recipients of donor TNFbeta(1,2) (n = 27) demonstrated an intermediate picture with less fibrosis (56%, P < 0.01) and less rejection (37%, P < 0.01) than TNFbeta(1,1). Recipients with donor IL16(TC) (n = 22) showed less recurrence (65% vs. 78%, P = 0.05), less fibrosis (53% vs. 67%, P = 0.06), and less rejection (41% vs. 55%, P = 0.06) than IL16(TT) (n = 32) genotype. Recipients of the combination TNFbeta(2,2)/IL16(TC) donor genotype had the most benign clinical outcome with less recurrence (33% vs. 75%, P < 0.01), no fibrosis (0% vs. 50%, P < 0.001), and fewer rejections (33% vs. 75%, P < 0.01) than donor TNFbeta(1,1)/IL16(TT) genotype. In vitro production of cytokines correlated with genotype. Release of soluble TNFbeta for TNFbeta(1,1) vs. TNFbeta(1,2) and TNFbeta(2,2) was 4803 +/- 2142 pg/mL vs. 5629 +/- 3106 (P = not significant [ns]) and 7180 +/- 3005 (P = ns). Release of soluble IL16 for IL16(TT) vs. IL16(TC) was 437 +/- 86 pg/mL vs. 554 +/- 39 (P = 0.06). In conclusion, allograft TNFbeta and IL16 gene polymorphisms may be useful markers to predict the severity of disease recurrence among HCV+ patients after liver transplantation.

Genes and (auto)immunity in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic autoimmune cholestatic liver disease most commonly encountered in postmenopausal women; it is characterized by high-titer serum autoantibodies to mitochondrial antigens, elevated serum IgM, progressive destruction of intrahepatic bile ducts, and ultimately liver cirrhosis and failure. The cytopathic mechanisms leading to the selective destruction of intrahepatic cholangiocytes are still largely unknown. The current theory on the pathogenesis of PBC indicated that environmental factors might trigger autoimmunity in genetically susceptible individuals. In fact, genetic predisposition is critical to disease onset and progression, yet peculiar among autoimmune diseases, as indicated by the lack of a strong association with major histocompatibility complex haplotypes. Further, the recently reported concordance rate among monozygotic twins strengthens the importance of genetic factors, while also indicating that additional factors, possibly infectious agents or xenobiotics, intervene to trigger the disease. In this review, the available data regarding the genetic factors associated with PBC susceptibility and progression, as well as the available evidence regarding the immunomediated pathogenesis of PBC, will be critically illustrated and discussed.

Effect of ischemic preconditioning on rat liver microcirculation monitored with laser Doppler flowmetry

BACKGROUND

Ischemic preconditioning (IP) may protect the liver from ischemia-reperfusion (I-R) injury during liver resection. This study investigated the effect of IP on hepatic microcirculation (HM) and analyzed the objective parameters of the HM using laser Doppler flowmetry (LDF).

METHODS

We used male Wistar rats (250-280 g) that underwent normothermic, segmental liver ischemia. The animals were divided into eight groups: 30, 45, 60, and 90 min of ischemia with, or without, IP. Five minutes ischemia and 10 min reperfusion, in two cycles, were used to elicit IP. Changes of the hepatic microcirculation were studied by LDF with on-line computer monitoring and processing. Histological alterations, liver enzymes, bilirubin, and TNF-alpha level were all measured simultaneously.

RESULTS

Reperfusion was assessed by post-ischemia flux plateau maximum (PM) and by the area under the reperfusion-curve (RA). Both PM and RA are inversely correlated with the duration of ischemia. The groups with IP had significantly (P < 0.05) higher flow values than groups without preconditioning. IP before liver ischemia resulted in significantly (P < 0.05) lower TNF-alpha levels at the end of the 30-min reperfusion. Lower serum ALT, LDH, and bilirubin levels could only be observed at 45 and 60 min I-R during the first post-operative day. On the seventh post-operative day there were no significant differences between the I-R and IP + IR groups in any of these parameters.

CONCLUSION

The benefit of ischemic preconditioning on hepatic microcirculation was well demonstrated with this method, which has never been described before, in this context. Changes in hepatic microcirculation can be precisely investigated by laser Doppler flowmetry using the standardization and transformation described in this paper.

Cytokine gene polymorphism and early graft rejection in liver transplant recipients

Cytokines, which play important roles in allograft rejection, show variable production among individuals. These variations may be related to genetic polymorphisms within the regulatory regions of the cytokine genes. We investigated the association between the role tumor necrosis factor alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), interferon gamma (IFN-gamma), interleukin (IL)-10 and IL-6 gene polymorphisms and early graft rejection among liver transplant recipients. Forty-three liver transplant recipients enrolled in this study were divided into 2 groups based on events in the first 2 months posttransplantations, namely, those experiencing at least 1 rejection episode (n = 26) or those without any episode (n = 17). The allele or genotype frequencies of cytokine gene polymorphisms showed no difference between liver recipients with or without nonrejection. In conclusion, there was no significant correlation between early graft rejection and cytokine gene polymorphism of TNF-alpha, TGF-beta, IL-10, IL-6, and IFN-gamma in liver transplant recipients.

From bases to basis: linking genetics to causation in primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a multifactorial autoimmune disease with inherited and environmental components in pathogenesis. It is exceptional among autoimmune diseases in showing strong heritability according to familial occurrence and monozygotic twins concordance, yet with weak associations with the usual genetic risk elements for autoimmunity, such as the HLA alleles. Among the latter, there is risk (at least in some populations) conferred by HLA DRB1*08 and possibly some protection by DRB1*11. However, the inconsistency among studies on HLA is surprising, given that PBC is a relatively homogenous disease entity. Among non-HLA genes, some studies implicate polymorphisms of genes for cytotoxic T-lymphocyte antigen-4, interleukin-2, or interleukin-10; polymorphisms of the vitamin D receptor could synergize with low sunlight exposure to create deficiency of the immunoregulatory factor, activated vitamin D. A new lead is available from the finding in female subjects with PBC of an increase in the degree of monosomy of the X chromosome that is presumed to carry immune response genes. A further suggested source of inquiry is the apparent protection of African-American women from PBC. Finally, data on inheritance should be sought in PBC by descent methodology, rather than by cross-sectional association studies in cases and control subjects, and based on analysis of a large number of families with an affected member through a worldwide effort.

Cytokine gene polymorphisms and acute liver graft rejection: a meta-analysis

In the field of liver transplantation, 7 reports have been published investigating the association between polymorphisms in cytokine genes and the occurrence of acute rejection in liver graft recipients. However, most of the individual studies lack the statistical power to detect a small-to-moderate effect of cytokine gene polymorphisms on the acute rejection rate. To overcome this problem, we performed a quantitative meta-analysis of 7 gene-association studies that were comparable with regard to definition of acute rejection and the type of immunosuppression used. In the overall analysis, the interleukin (IL)-10 polymorphism at position -1082 was identified as a genetic risk factor for acute liver graft rejection; liver transplant recipients carrying the IL-10 -1082.A allele displayed a lower rejection rate (common odds ratio [OR], .6; 95% confidence interval [CI], .4-.9). For the tumor necrosis factor (TNF)-A -308 polymorphism, a common OR could not be calculated due to significant heterogeneity of ORs between the studies (mean OR, 1.4; 95% CI, .8-2.6). No associations were found between acute liver graft rejection and single nucleotide polymorphisms in the IL-6 (position -174) and transforming growth factor (TGF)-beta1 (positions +869 and +915) genes. In conclusion, results from this meta-analysis suggest a role for the IL-10 -1082 polymorphism in human liver graft rejection.

Association of -238G/A polymorphism of tumor necrosis factor-alpha gene promoter region with outcomes of hepatitis B virus infection in Chinese Han population

AIM: To clarify whether -238G/A polymorphism of tumor necrosis factor-α (TNF-α) gene promoter region was associated with outcomes of hepatitis B virus (HBV) infection in Han population of northern China, and to analyze the gene-environment interaction between -238G/A polymorphism and cigarette smoking or alcohol consumption.

METHODS: A case-control study was conducted to analyze the association of TNF-α gene promoter polymorphism with HBV infection outcomes. A total of 207 patients with chronic hepatitis B (HB) and 148 cases of self-limited HBV infection from Ditan Hospital and Shunyi District Hospital in Beijing, respectively were recruited. History of smoking and alcohol drinking was inquired by a questionnaire. The -238G/A polymorphism of TNF-α gene promoter was genotyped by polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP).

RESULTS: The frequencies of GG and GA genotypes were 98.07% and 1.93% in chronic HB patients and 93.24% and 6.76% in self-limited HBV infection individuals, respectively (χ² = 5.30, P = 0.02). The frequency of G allele was significantly higher in patients with chronic HB that in individuals with self-limited HBV infection (99.03% vs 96.62%, χ² = 5.20, P = 0.02). Only modestly increased risk of onset of chronic HB was found in smokers (OR = 1.40, 95% CI: 0.87-2.28, P = 0.14) and drinkers (OR = 1.26, 95% CI: 0.78-2.05, P = 0.32). There was a positive interaction between genotype GG and cigarette smoking with an interaction index (II) of 2.95, or alcohol consumption with an II of 1.64.

CONCLUSION: The -238G/A polymorphism of TNF-α gene promoter region is independently associated with different outcomes of HBV infection.

Autoimmune liver disease

PURPOSE OF REVIEW

Identify advances in diagnosis, treatment, and understanding of autoimmune hepatitis.

RECENT FINDINGS

Autoimmune hepatitis can present as an acute or fulminant hepatitis in the absence of pre-existent fibrotic disease. Celiac disease can resemble it, and treatment must include corticosteroids. Centrilobular necrosis is within the histologic spectrum of autoimmune hepatitis, and variant syndromes may be refractory to conventional therapies. Discriminative indices developed by head-to-head comparisons between the classical disorders may be useful in identifying true variants, and antibodies to chromatin may have prognostic value in predicting relapse after drug withdrawal. Multiple drugs and infectious agents can trigger the disease, and cytokine imbalances are important pathogenic factors. Recurrent or de novo autoimmune hepatitis must be considered as a cause of graft dysfunction after liver transplantation. Pregnancy is generally well tolerated, and it may attenuate the disease. After transplantation, pregnancy should be deferred until after the second year.

SUMMARY

Autoimmune hepatitis has diverse presentations and manifestations. It must be considered in all patients with acute and chronic liver disease and in all cases of allograft dysfunction after liver transplantation.