Polymorphisms in cytokines and growth factor genes and their association with acute rejection and recurrence of hepatitis C virus disease in liver transplantation

Influence of IL-18 and IL-10 Polymorphisms on Tacrolimus Elimination in Chinese Lung Transplant Patients

Aims. The influence of interleukin-10 (IL-10) and interleukin-18 (IL-18) polymorphisms on tacrolimus pharmacokinetics had been described in liver and kidney transplantation. The expression of cytokines varied in different kinds of transplantation. The influence of IL-10 and IL-18 genetic polymorphisms on the pharmacokinetic parameters of tacrolimus remains unclear in lung transplantation. Methods. 51 lung transplant patients at Shanghai Pulmonary Hospital were included. IL-18 polymorphisms (rs5744247 and rs1946518), IL-10 polymorphisms (rs1800896, rs1800872, and rs3021097), and CYP3A5 rs776746 were genotyped. Dose-adjusted trough blood concentrations (C/D ratio, mg/kg body weight) in lung transplant patients during the first 4 postoperative weeks were calculated. Results. IL-18 rs5744247 allele C and rs1946518 allele A were associated with fast tacrolimus metabolism. Combined analysis showed that the numbers of low IL-18 mRNA expression alleles had positive correlation with tacrolimus C/D ratios in lung transplant recipients. The influence of IL-18 polymorphisms on tacrolimus C/D ratios was observed in CYP3A5 expresser recipients, but not in CYP3A5 nonexpresser recipients. No clinical significance of tacrolimus C/D ratios difference of IL-10 polymorphisms was found in our data. Conclusions. IL-18 polymorphisms may influence tacrolimus elimination in lung transplantation patients.

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.

Association between transforming growth factor beta-1 +869T/C polymorphism and acute rejection of solid organ allograft: A meta-analysis and systematic review

BACKGROUND

Transforming growth factor beta-1(TGFB1) is involved in the acute rejection (AR) episodes of solid organ transplant recipients. However, results from published studies on the association between donor/recipient TGFB1 +869T/C polymorphism and AR risk are conflicting and inconclusive.

METHODS

PUBMED, EMBASE, CNKI and Wanfang Database were searched to identify eligible studies investigating the association between donor/recipient TGFB1 +869T/C polymorphism and AR risk. Statistical analysis was performed by using STATA 10.0.

RESULTS

A total of 29 studies were included. Overall, the donor TGFB1 +869T/C polymorphism was significantly associated with AR risk in heterozygote comparison (CT vs. TT: OR = 1.67, 95%CI, 1.17-2.39; P heterogeneity=0.285) and dominant model (CC vs.

TC/TT

OR = 1.47, 95%CI, 1.05-2.06; P heterogeneity=0.445). In addition, subgroup analysis revealed that CT variant (CT vs. TT: OR = 1.97, 95%CI, 1.20-3.25; P heterogeneity = 0.777) and CC/CT genotype (CC/CT vs. TT: OR = 1.72, 95%CI, 1.07, 2.78; P heterogeneity = 0.619) within donors contributed to higher risk of AR in recipients administrated with CsA or FK506, compared with those applied only CsA. On the other hand, no significant association between recipient TGFB1 +869T/C polymorphism and AR was detected in all genetic models.

CONCLUSIONS

This meta-analysis and systematic review suggested that donor TGFB1 +869T/C polymorphism was significantly associated with AR of solid organ transplant recipients, and especially among patients in CsA/FK 506 group compared with those in CsA group.

Genetic variants of STAT-4 affect the development of graft fibrosis after liver transplantation for HCV-induced liver disease

BACKGROUND

Hepatitis C virus (HCV) reinfection after liver transplantation may lead to recirrhosis and seems to be influenced by genetic factors. The aim of our study was to evaluate the role of STAT-4-polymorphisms in the development of HCV-related graft disease based on protocol biopsies.

METHODS

One hundred sixty transplant patients with HCV recurrence were genotyped for STAT-4 (rs7574865) by polymerase chain reaction. Fibrosis stages were determined based on Desmet and Scheuer classification. SPSS was used for the statistical analysis of genotype distribution and of time to the development of advanced fibrosis among the genotypes.

RESULTS

During a comparable observation period of 86.2 months (P=0.654), 65 patients (46.5%) developed advanced fibrosis. Advanced fibrosis was observed significantly more frequent in patients (n=34) with at least one T-allele (53.1 vs. 32.3%; P=0.013) compared with homozygotes for G-allele (n=31). Significant differences in the duration of advanced fibrosis development were detected between patients with at least one T-allele compared with G-allele (34.4 vs. 49.0 months; P=0.022). No impact was observed regarding the outcome of interferon-based antiviral treatment (P=0.297) and the occurrence of acute cellular rejection (P=0.365).

CONCLUSION

Present results indicate a possible impact of genetic confounders in the recipient on graft fibrogenesis, thus explaining significantly different graft behavior observed after transplantation for HCV-associated liver disease. STAT-4-T-allele is identified as fibrogenic factor and seems to have a negative impact on HCV-induced fibrosis development.

Recipient IL-6-572C/G genotype is associated with reduced incidence of acute rejection following liver transplantation

OBJECTIVE

Acute rejection resulting from alloimmune responses is a major risk factor affecting patient survival following liver transplantation. Since interleukin (IL)-6 can mediate acute rejection, the association between IL-6 gene single nucleotide polymorphisms (SNPs) and incidence of acute rejection in liver transplant recipients was investigated.

METHODS

Patients who received liver transplant between January 2005 and December 2010 were typed for IL6-572C/G (rs1800796) polymorphisms using the snapshot technique. Association between genotype and acute rejection was analysed using the SNP Statistics website: http://bioinfo.iconcologia.net/snpstats/start.htm. Allelic and genotypic distributions for rs1800796 were compared among 335 patients with or without acute rejection within the first 6 months following liver transplant.

RESULTS

Incidence of acute rejection was 11.94%. A heterozygous CG genotype for IL6-572C/G was associated with a lower acute rejection rate compared with homozygous CC or GG genotypes.

CONCLUSION

IL6-572 CG genotype may be related to protection from acute rejection following liver transplant in Han Chinese patients.

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.

Role of IL28B polymorphism in the development of hepatitis C virus-induced hepatocellular carcinoma, graft fibrosis, and posttransplant antiviral therapy

BACKGROUND

The development of liver graft disease is partially determined by individual genetic background. Interleukin 28B (IL28B) is strongly suspected to be involved in susceptibility for hepatitis C virus (HCV) infection, inflammation, and antiviral treatment response before and after liver transplantation (LT). Currently, the role of IL28B polymorphism (rs12979860) in the development of hepatocellular carcinoma (HCC) is unclear, and only limited data are available on the course of HCV recurrence.

METHODS

One hundred sixty-seven HCV-positive patients after LT were genotyped for IL28B (C→T; rs12979860). Sixty-one patients with histologically confirmed HCC in the explanted liver were compared with 106 patients without HCC regarding IL28B genotypes. Among patients with HCC, IL28B genotypes were correlated with tumor histology and pretransplant α-fetoprotein (AFP) levels. Furthermore, the role of IL28B polymorphism was evaluated regarding interferon-based treatment success and fibrosis progression after LT.

RESULTS

The prevalence of HCC in explanted livers was significantly higher among patients with TT genotype, suggesting a protective role of the C allele in HCC development (P=0.041). Median AFP level was closely to significance higher in the presence of T allele (P=0.052). Significant differences in IL28B genotype distribution were detected between AFP-negative and AFP-positive HCCs (<15 μg/L vs. >15 μg/L; P=0.008). Although no impact could be observed regarding acute cellular rejection (P=0.940), T allele was significantly associated with antiviral therapy failure (P=0.028) and faster development of advanced fibrosis (P=0.017) after LT.

CONCLUSION

IL28B polymorphism seems to be involved in the development of HCV-induced HCC and in the course of HCV recurrence after LT. T allele may be regarded as a genetic risk factor for HCV-related carcinogenesis, posttransplant fibrosis progression, and antiviral therapy failure.

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.

Transforming growth factor β1 polymorphisms and progression of graft fibrosis after liver transplantation for hepatitis C virus--induced liver disease

Re-infection with the hepatitis C virus (HCV) is an important development after liver transplantation (LT); it can lead to graft fibrosis. The aim of this study was to assess the role of transforming growth factor β1 (TGF-β1) polymorphisms in the development of HCV-related graft disease by evaluating protocol liver biopsies. A total of 192 patients with a recurrence of HCV infection after LT were genotyped for TGF-β1 codon 10 (C→T) and codon 25 (G→C) using the polymerase chain reaction. Histological evaluation of 614 protocol liver biopsies obtained from these patients was undertaken using the classification of Desmet and Scheuer to stage the degree of fibrosis. Mild stages of fibrosis (0-2) were compared to advanced stages of fibrosis (3-4) that developed during the period of infection with the virus. Correlations between the prevalence of TGF-β1 genotypes and the different degrees of fibrosis that developed were determined. No statistically significant differences were found for genotype distributions (codons 10 and 25) with respect to recipient age, donor sex, occurrence of acute cellular rejection, and response to antiviral therapy. However, the C allele at codon 25 was significantly less frequent in the group with advanced fibrosis (P = 0.001). Furthermore, a positive association was found between progression of fibrosis and male recipient sex (P = 0.024), donor age (P = 0.041), and viral genotype 1b (P = 0.002). In conclusion, this study, in which the evolution of hepatic fibrosis was assessed histologically in a large cohort of patients with HCV re-infection after LT, has demonstrated that the C allele at codon 25 of the TGF-β1 gene is a marker for the development of graft fibrosis.

Polymorphisms in cytokine genes and their association with acute rejection and recurrence of hepatitis B in Chinese liver transplant recipients

BACKGROUND

Acute rejection (AR) and hepatitis B virus (HBV) recurrence after liver transplantation (LT) are the two major complications leading to chronic graft dysfunction. Genomic polymorphisms in interleukin (IL)-10, tumor necrosis factor (TNF)alpha and transforming growth factor (TGF)beta1 genes have been found to affect the susceptibility to certain diseases. However, the relationship between cytokine gene polymorphisms and risk of AR as well as HBV recurrence after LT in Han Chinese has not been reported. The objective of the present study was to investigate the association of polymorphisms within these cytokine genes with the risk of AR as well as HBV recurrence.

METHODS

One hundred eighty six Chinese LT recipients in which 41 patients developed AR and 29 patients experienced HBV recurrence were enrolled; 151 age- and gender-matched healthy individuals were selected as controls. Single-nucleotide polymorphisms (SNPs) at loci of IL-10 -1082, -819, -592, and TNFalpha -308, -238, as well as TGFbeta1 -988, -800, -509, +869, and +915 were determined by using DNA sequencing and then confirmed by restriction fragment length polymorphism (PCR-RFLP). Analyses of linkage disequilibrium and haplotype frequency were performed using Haploview program.

RESULTS

The -819 and -592 polymorphisms in the IL-10 gene were in complete linkage (r(2) = 1). Another linkage was found at -509 and +869 in the TGFbeta1 gene (r(2) = 0.66). A significant difference was observed in the distribution of allelic frequencies at position -819 and -592 in the IL-10 gene between ARs and non-ARs (p = 0.036, OR = 1.134, 95% CI 0.999-1.287 and p = 0.036, OR = 1.134, 95% CI 0.999-1.287, respectively). After adjustment for a Bonferroni correction, there was no significant difference between the polymorphism and AR (p >0.05). Furthermore, the overall genotype distribution between HBV recurrence patients and non-HBV recurrence patients was also not significantly different (p >0.05).

CONCLUSIONS

Our study suggests that gene polymorphisms of IL10, TNFalpha, and TGFbeta1 do not have a major independent role in AR and HBV recurrence after LT and may not be risk factors of AR and HBV recurrence after LT in Chinese liver transplant recipients.

Effect of the interleukin-6 C174G gene polymorphism on treatment of acute and chronic hepatitis C in human immunodeficiency virus coinfected patients

Hepatitis C virus (HCV)/human immunodeficiency virus (HIV) coinfection poses a difficult therapeutic problem. Response to HCV-specific therapy is variable but might be influenced by host genetic factors, including polymorphisms of cytokine genes. Here, we studied whether interleukin-6 (IL-6) C174G gene polymorphism affects the response to antiviral treatment in HCV-infected HIV-positive subjects. We determined IL-6 genotypes in HIV-positive patients with acute (n = 52) and chronic (n = 60) hepatitis C treated with pegylated interferon-alpha. Two hundred ten HCV monoinfected, 197 HIV monoinfected, and 100 healthy individuals were studied as controls. Patients were classified into high and low producers according to IL-6 genotypes. Rates of sustained virological responses (SVRs) were compared between the IL-6 genotypes. Signal transducer and activator of transcription three phosphorylation was analyzed by Western blot in HCV core-transfected human hepatoma cell line (HUH7) cells. Distribution of IL-6 genotypes did not differ significantly between the study groups. SVR was achieved in 63% of HIV/HCV coinfected patients. Carriers of the IL-6 high producer (HP) genotype had significantly higher SVR rates than patients with an IL-6 low producer genotype (70.1% versus 52%; P < 0.002). This effect was seen in both HIV-positive patients with acute (74% versus 33%; P < 0.05) and chronic (66% versus 33%; P < 0.05) hepatitis C. Multivariate analysis confirmed IL-6 HP carriage as an independent positive predictor for SVR (Odd's ratio 6.1; P = 0.004). This effect corresponds to the in vitro observation that in HCV core-transfected HUH7 cells, IL-6 overcomes the HCV core-mediated inhibition of STAT3 activation.

CONCLUSION

Response rates to HCV-specific treatment are higher in HCV/HIV-positive patients carrying the IL-6 HP genotype, which might be because of IL-6 mediated STAT3 activation.

Polymorphisms of tumor necrosis factor-alpha, interleukin-10, cytochrome P450 3A5 and ABCB1 in Chinese liver transplant patients treated with immunosuppressant tacrolimus

BACKGROUND

Cytokine production in the host immune response after transplantation may contribute to the variable CYP3A-dependent drug disposition. We investigated the effect of TNF-alpha, IL-10, CYP3A5 and ABCB1 polymorphisms on immunosuppressant tacrolimus pharmacokinetics in liver transplant patients.

METHODS

Genetic polymorphisms in TNF-alpha, IL-10, CYP3A5 and ABCB1 were studied in 70 liver transplant recipients and 70 donors. Tacrolimus dosage and blood concentration were investigated at 1, 2 and 3 weeks after transplantation.

RESULTS

The IL-10 G-1082A polymorphism in recipients was significantly associated with tacrolimus concentration/dose (C/D) ratios (IL-10-1082GG < GA < AA) within the first 3weeks posttransplantation (P < 0.05). Recipients with the capacity for low IL-10 production (-1082AA) carrying CYP3A5 non-expressor (CYP3A5()3/()3) liver had the highest C/D ratios (mean: 172.4, 161.7, 160.3 for 1, 2 and 3 weeks posttransplantation, respectively), whereas recipients with intermediate or high production of IL-10 (-1082GA or GG) engrafted with CYP3A5 expressor (CYP3A5()1 carrier) liver were found to have the lowest ratios (96.4, 78.0 and 75.4, respectively, P < 0.01).

CONCLUSIONS

The IL-10 G-1082A and CYP3A5()3 polymorphisms may influence the interindividual variability of tacrolimus pharmacokinetics in Chinese liver transplant patients. This finding provided a new interpretation for the variable immunosuprressant disposition after transplantation.

Genetic polymorphisms of inflammatory cytokines and liver fibrosis progression due to recurrent hepatitis C

To ascertain whether single nucleotide polymorphisms (SNPs) regulating the expression of interferon-gamma (IFN-gamma), IFN-gamma receptor-1 (IFNGR-1), interleukin-6 (IL-6), IL-10, IL-18, and tumor necrosis factor-alpha (TNF-alpha) may be associated with early fibrosis progression of recurrent hepatitis C, 50 liver transplantation recipients (32 men, 18 women, median age 56 years) with a median histologic follow-up time of 54 months were studied; 98 healthy blood donors served as controls. Cytokine SNPs were determined by means of previously described PCR-based methods. On the basis of the SNP studies, a low, intermediate, or high producer cytokine phenotype was attributed to each patient. Only 1 of the 17 low IL-10 producers reached an Ishak staging score > 2, in contrast to 20 of the 33 patients who were intermediate or high IL-10 producers (Mantel-Cox, p < 0.005). Recipients who were low IL-10 producers and high IFN-gamma producers had significantly slower fibrosis progression in comparison to intermediate/high IL-10 producers and low IFN-gamma producers (p < 0.005). In conclusion, cytokine SNPs resulting in high and low producer phenotypes of both Th1 and Th2 cytokines appear to modulate the course of recurrent hepatitis C. Low IL-10 producers are those with the slowest histologic fibrosis progression.

TGF-beta1 gene polymorphism in liver graft recipients

Cytokines are known to be important mediators during liver graft outcome and their gene polymorphism could affect the overall expression and secretion of cytokines. In this retrospective study, we analyzed the effect of TGF-beta1 polymorphism in 150 liver allograft recipients. Genotyping PCR-SSP were performed for TGF-beta1 gene (codon 10T/C and 25C/G). TGF-beta1 polymorphism at codon 10 and 25 correlate borderline with liver graft acceptance and when the combination between codon 10 and 25 was analyzed, it revealed that T/T G/C genotype and the TC haplotype were significantly associated with graft acceptance (p<0.05). TGF-beta1 high secretor phenotype was also increased in the acute rejection group close to significance (p=0.06). In conclusion, these findings show a correlation between TGF-beta1 gene polymorphism and liver graft acceptance.

The risk of dialysis access thrombosis is related to the transforming growth factor-beta1 production haplotype and is modified by polymorphisms in the plasminogen activator inhibitor-type 1 gene

Transforming growth factor-beta1 (TGF-beta1) and plasminogen activator inhibitor-type 1 (PAI-1) might play a role in the development of fibrosis and stenosis of hemodialysis vascular accesses. We studied polymorphisms in the TGFbeta1 (869T>C; 915G>C), and PAI-1 (4G/5G) genes in 416 hemodialysis patients (107 access thrombosis cases, 309 controls), to determine if they are related to vascular access thrombosis. Three TGF-beta1 production haplotypes (low, intermediate, and high) were defined according to the combination of polymorphisms found. The adjusted odds ratio (OR) and 95% confidence interval (CI) for access thrombosis in low TGF-beta1 producers was 7.31 (2.15-24.88; P = .001). The interaction between low TGF-beta1 production haplotype and the 4G/4G PAI-1 genotype was strongly associated with access thrombosis (adjusted OR 19.3; 95% CI 2.82-132.40; P = .003). Mean access thrombosis-free survival times in years (95% CI) were 14.65 (12.05-17.25), 11.96 (8.67-15.25), and 4.94 (3.06-6.83) in high, intermediate, and low TGF-beta1 producers, respectively (P = .044). Analysis of the synergy index and the case-only cross-product supported the presence of an interaction. We concluded that low TGF-beta1 production haplotype is a risk factor for hemodialysis access thrombosis and that in the presence of the 4G/4G PAI-1 genotype there is an additional increase in risk.

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.

Role of tumor necrosis factor-alpha and interleukin-10 gene polymorphisms in irritable bowel syndrome

OBJECTIVES

Imbalances in the genetically controlled pro- and anti-inflammatory cytokine production may promote ongoing low-grade inflammation after an acute gastroenteritis, and subsequently, irritable bowel syndrome (IBS) (post-infectious IBS, PI-IBS). We studied gene promoter single nucleotide polymorphisms (SNPs) of tumor necrosis factor-alpha (TNF-alpha, pro-inflammatory) and interleukin-10 (IL-10, anti-inflammatory) in IBS patients and controls.

METHODS

DNA was extracted from peripheral blood leucocytes of 111 IBS patients and 162 healthy controls. Genotype and allele frequencies were assessed by analyzing SNPs at position -308 (TNF-alpha) and -1082 and -819 (IL-10).

RESULTS

Homozygous high producers for TNF-alpha (A/A) were rare (overall prevalence 2.6%). The heterozygous TNF-alpha genotype (G/A, high producer) was significantly more prevalent in IBS compared to controls (41%vs 26%, p= 0.02). More patients (41%) than controls (30%) were positive for the A allele (p= 0.044; odds ratio (OR) 1.68, 95% confidence interval (CI) 1.01-2.79), with a similar trend for diarrhea (54%) versus constipation and alternating subtypes (<33%, p= 0.079), but not for subgroups according to a history of acute gastroenteritis. IL-10 genotypes were similarly distributed in patients and controls for both SNPs. Possession of a high producer TNF-alpha and a low producer IL-10 genotype were significantly more prevalent in IBS (9%) versus controls (3%, p= 0.035; OR 3.11, 95% CI 1.03-9.36) and in diarrhea (20%) compared to other IBS subtypes (<4%, p= 0.026).

CONCLUSIONS

Our results support the emerging hypothesis that genetically determined immune activity plays a role in the pathophysiology of IBS. Future studies in larger, clinically relevant, IBS subgroups are warranted to establish definite associations with cytokine gene polymorphisms.

IL-6 and IL-10 promoter gene polymorphisms of patients and donors of allogeneic sibling hematopoietic stem cell transplants associate with the risk of acute graft-versus-host disease

The present study aimed to determine existing associations between single nucleotide polymorphisms within the promoters of interleukin (IL)-6 (-174 G/C) and IL-10 (-1082 G/A, -819 C/T, -592 C/A) genes and the outcome of allogeneic sibling hematopoietic stem cell transplantation. Ninety-three recipients and 74 donors were typed for IL-6 and IL-10 alleles by polymerase chain reaction-sequence specific primer. Then, IL-6 activity in patient serum and the concentration of C-reactive protein were analyzed at various times after transplantation in relation to transplant complications and IL-6 genotype. IL-6 activity in serum was significantly higher in patients who died as a result of toxic complications and after the 6 weeks after transplantation in patients with severe acute graft-versus-host disease (aGVHD). Recipient IL-6 G genotype was associated with increased IL-6 activity and C-reactive protein production. In univariate analyses, recipient IL-6 G and donor IL-6 GG associated or tended to associate with increased risk for aGVHD. In contrast, recipient IL-10 GCC/GCC and donor IL-10 ACC decreased the risk of aGVHD. IL-6 and IL-10 polymorphic features, together with other factors known to affect the risk of aGVHD, were also subjected to multivariate analyses. These analyses confirmed the independent contribution of recipient IL-10 GCC/GCC (odds ratio = 0.085, p = 0.046) and donor IL-6 GG (odds ratio = 3.934, p = 0.034) genotypes to the risk of aGVHD.

Thrombophilia and the Risk for Hemodialysis Vascular Access Thrombosis

Vascular access thrombosis is the most common and costly complication in hemodialysis patients. The role of thrombophilia in access thrombosis is not established. A case-control study was conducted of 419 hemodialysis patients to determine whether thrombophilia was associated with arteriovenous fistula or graft thrombosis. Participants were enrolled from three in-center and five satellite dialysis units associated with a Canadian academic health science center that provides dialysis services in a catchment area of one million. Patients were tested for factor V Leiden, prothrombin gene mutation, factor XIII genotype, methylenetetrahydrofolate reductase genotype, lupus anticoagulant, anticardiolipin antibody, factor VIII, homocysteine, and lipoprotein (a) concentrations. Overall, 59 (55%) patients with access thrombosis had at least one thrombophilia compared with 122 (39%) patients without access thrombosis (unadjusted odds ratio [OR], 1.91; 95% confidence interval [CI], 1.23 to 2.98). After controlling for important risk factors, the association between any thrombophilia and access thrombosis remained (adjusted OR, 2.42; 95% CI, 1.47 to 3.99). For each additional thrombophilic disorder, the odds of access thrombosis increased significantly (adjusted OR, 1.87; 95% CI, 1.34 to 2.61). This study suggests that thrombophilia is associated with access thrombosis in dialysis patients. Large, multicenter, prospective cohort studies are needed to confirm the observations from this case-control study.

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.