Luydson Richardson Silva Vasconcelos

IL-22 and IL-22 binding protein (IL-22BP) regulate fibrosis and cirrhosis in hepatitis C virus and schistosome infections

Interleukin (IL)‐22 acts on epithelia, hepatocytes, and pancreatic cells and stimulates innate immunity, tissue protection, and repair. IL‐22 may also cause inflammation and abnormal cell proliferation. The binding of IL‐22 to its receptor is competed by IL‐22 binding protein (IL‐22BP), which may limit the deleterious effects of IL‐22. The role of IL‐22 and IL‐22BP in chronic liver diseases is unknown. We addressed this question in individuals chronically infected with schistosomes or hepatitis C virus (HCV). We first demonstrate that schistosome eggs stimulate production of IL‐22 transcripts and inhibit accumulation of IL22‐BP transcripts in schistosome‐infected mice, and that schistosome eggs selectively stimulate production of IL‐22 in cultures of blood leukocytes from individuals chronically infected with Schistosoma japonicum. High IL‐22 levels in cultures correlated with protection against hepatic fibrosis and portal hypertension. To test further the implication of IL‐22/IL‐22BP in hepatic disease, we analyzed common genetic variants of IL22RA2, which encodes IL‐22BP, and found that the genotypes, AA, GG of rs6570136 (P = 0.003; odds ratio [OR] = 2), and CC, TT of rs2064501 (P = 0.01; OR = 2), were associated with severe fibrosis in Chinese infected with S. japonicum. We confirmed this result in Sudanese (rs6570136 GG [P = 0.0007; OR = 8.2], rs2064501 TT [P = 0.02; OR = 3.1]), and Brazilians (rs6570136 GG [P = 0.003; OR = 26], rs2064501 TC, TT (P = 0.03; OR = 11]) infected with S. mansoni. The aggravating genotypes were associated with high IL22RA2 transcripts levels. Furthermore, these same variants were also associated with HCV‐induced fibrosis and cirrhosis (rs6570136 GG, GA [P = 0.007; OR = 1.7], rs2064501 TT, TC (P = 0.004; OR = 2.4]). Conclusions: These results provide strong evidence that IL‐22 protects against and IL‐22BP aggravates liver fibrosis and cirrhosis in humans with chronic liver infections. Thus, pharmacological modulation of IL‐22 BP may be an effective strategy to limit cirrhosis. (Hepatology 2015;61:1321–1331)

High Frequency of Variant Alleles of the Mannose-Binding Lectin 2 (MBL2) Gene Are Associated with Patients Infected by Hepatitis B Virus

Patients with hepatitis B virus (HBV) infection may develop severe chronic liver disease. Carriers of HBV have an increased risk of developing cirrhosis, hepatic decompensation, and hepatocellular carcinoma. Worldwide an estimated 350 million people are infected with HBV, and 15-40% will develop serious sequelae in their lifetime. In our study we investigated the association of single nucleotide polymorphisms (SNPs) in the first exon and promoter region of the mannose-binding lectin gene 2 (MBL2) situated on chromosome 10, with susceptibility to HBV infection. One-hundred and two patients infected with HBV were included in this study, and 232 uninfected individuals were used as healthy controls. Genotyping of the first exon (alleles A/O) was performed using a melting temperature assay. Genotyping of the promoter region (-550 H/L; -221 Y/X) was performed using the Taqman PCR technique. In the HBV-infected group we found a significantly increased frequency of haplotypes associated with low serum MBL. Our findings may indicate that MBL has a protective role against HBV infection in the studied population.

TNF-α and IL-10 polymorphisms increase the risk to hepatocellular carcinoma in HCV infected individuals

Hepatitis C virus (HCV) is the major cause of hepatocellular carcinoma (HCC). The risk to develop HCC increases with the severity of liver inflammation and hepatic fibrosis. It is believed that a balance between the releases of pro‐ and anti‐inflammatory cytokines will determine the clinical course of HCV and the risk to develop HCC. The inteleukin‐10 (IL‐10) and the tumor necrosis factor alpha (TNF‐α) play key roles in the Th1 and Th2 balance during the inflammatory response against HCV. The aim of the present study was to investigate the association between polymorphisms in TNF‐α ‐308 G>A (rs1800629), IL‐10 ‐1082 G>A (rs1800896) and ‐819/‐592 (rs1800871/rs1800872) with HCC risk in individuals with HCV. The present study evaluated 388 chronic HCV patients. Polymorphisms were determined by real‐time PCR. Diplotypes associated with low IL‐10 production and the TNF‐α GG genotype were significantly associated with HCC occurrence after multivariate logistic regression analysis (P = 0.027 and P = 0.029, respectively). Additionally, the IL‐10 ‐819 (‐592) TT (AA) genotype was significantly associated with multiple nodules and HCC severity according to BCLC staging (P = 0.044 and P = 0.025, respectively). Patients carrying low production haplotypes of IL‐10 and the TNF‐α GG genotype have higher risk to develop HCC. J. Med. Virol. 88:1587–1595, 2016.

Association of hepatitis C virus infection and liver fibrosis severity with the variants alleles of MBL2 gene in a Brazilian population.

Mannose binding lectin (MBL) is a molecule of the innate immunity, which activates the complement system and modulates inflammation. We investigated the association of the polymorphisms in the exon 1 and promoter region of the MBL gene (MBL2) with the susceptibility to hepatitis C virus (HCV) infection and the degree of liver fibrosis in Brazilian patients chronically infected with HCV. The study was performed in 232 healthy control subjects and 186 patients, 157 of whom underwent liver biopsy after histopathology analysis and classification of fibrosis according to Metavir score. Exon 1 was genotyped by melting temperature assay and the promoter region by Taqman real-time polymerase chain reacation. The frequency of genotypes related to low production of MBL was higher in patients with HCV than in controls (p(c) = 0.0001, odds ratio = 3.52; confidence interval = 1.86-6.71). In addition, the frequency of variant haplotype, HYO was higher in patients with the severe fibrosis stage F4 (10.7%) than in patients with the mild/moderate fibrosis stage F1/F2 (3.4%), when compared with the HYA haplotype (p(c) = 0.04, odds ratio = 5.25, confidence interval = 1.11-23.62). We conclude that MBL variant alleles expressing low levels of MBL are associated with the susceptibility to HCV infection and that the inheritance of HYO haplotype could be associated with fibrosis severity.

Genetic variation in PTX3 and plasma levels associated with hepatocellular carcinoma in patients with HCV

Hepatitis C virus (HCV) is the main cause of chronic liver disease, cirrhosis and hepatocellular carcinoma (HCC) worldwide. The risk to develop HCC increases with the severity of liver inflammation and fibrosis. Long pentraxin 3 (PTX3) is a soluble pattern‐recognition receptor produced by phagocytes and nonimmune cells at sites of inflammation or injury. The aim of the present study was to determine the association of PTX3 polymorphisms and its plasma levels with HCC occurrence among patients with HCV. Samples from 524 patients with chronic hepatitis C were evaluated in this study. Two polymorphisms (rs1840680 and rs2305619) in the PTX3 gene were determined by real‐time PCR. PTX3 plasma levels were measured by Enzyme‐linked Immunosorbent Assay (ELISA). Our data show a significant association between PTX3 polymorphisms and HCC occurrence in univariate and multivariate analysis (P = 0.024). Patients with HCC had higher PTX3 plasma levels compared to individuals with mild or severe fibrosis (P < 0.0001 and P = 0.002, respectively). In addition, PTX3 rs2305619 polymorphism and plasma levels were correlated with Child‐Pugh scores B and C in HCC individuals. PTX3 seems to be a risk factor for HCC occurrence in chronic hepatitis C. This is the first study that evaluates PTX3 in the context of hepatitis C.

Plasma myeloperoxidase levels correlate with hepatocellular carcinoma in chronic hepatitis C

Myeloperoxidase (MPO) is an enzyme responsible for generating hypochlorous acid and reactive oxidants that may lead to liver injury and cancer in hepatitis C (HCV) infection. MPO expression level is regulated by a polymorphism in the promoter region -463 of MPO gene. In the current study, MPO plasma levels and the G-463A MPO polymorphism were determined in 158 chronically HCV infected patients with and without hepatocellular carcinoma (HCC). MPO plasma levels were determined using a commercially ELISA kit. The G-463A MPO polymorphism was accessed by real time PCR using TaqMan probes. The MPO plasma levels of patients with HCV-HCC were higher in comparison to patients with chronic hepatitis or with those patients with severe fibrosis (p=0.01 and p=0.04, respectively). The MPO G-463A polymorphism was not associated with HCV outcome. These findings suggest MPO levels monitoring may be a potential biological marker to HCC screening in patients with HCV.

Low IL10 serum levels as key factor for predicting the sustained virological response to IFNα/ribavirin in Brazilian patients with HCV carrying IL28B CT/TT genotype

PROPOSE IL28B polymorphisms rs12979860 CC genotype was associated to protection of HCV infection and sustained virological response (SVR) in HCV infected patients treated with pegIFNα/ribavirin (IFNα/RIB), however, this polymorphism frequency varies depending on genetic components. Studies with larger number of Brazilian individuals, determining IL28B polymorphisms is lacking. Regarding to treatment response, the levels of IL10 seem to influence response to IFNα/RIB therapy. Thus, the IL28B polymorphism frequency was investigated in health controls and infected HCV patients, as well as, in patients who reach SVR vs Non-SVR. Also, to gain insight into the interplay between IL28B genotypes, IL10 levels and therapy response, a subgroup of genotyped HCV patients SVR and Non-SVR were analyzed regarding the IL10 production. METHODS It was enrolled 487 HCV infected patients and 234 healthy individuals. Patients with response to IFNα/RIB were classified as SVR (n = 81) and Non-SVR (n = 123). TAQMAN probes were used for genotyping the SNP rs12979860, resulting in CC, CT or TT genotypes. In one hundred one patients, the levels IL10 were measured at week 4 of IFNα/RIB. RESULTS CC genotype was associated to SVR (p = 0.029) and its frequency was higher in healthy individuals vs patients (p = 0.02). Patients carrying CT/TT with IL10<10 pg/mL, had a chance of 2.72 to achieve SVR in multivariate model (p = 0.043). CONCLUSION CC genotype was associated to SVR and protection to HCV infection. Moreover, IL28B genotyping and IL10 serum levels could be further explored as a useful algorithm for identify the CT/TT SVR patients.

Mannose-binding lectin gene (MBL2) polymorphisms related to the mannose-binding lectin low levels are associated to dengue disease severity

Dengue is the main arbovirosis in the tropical and subtropical areas of the world. The majority of infected individuals present an asymptomatic outcome while others progress to dengue fever (DF) or dengue haemorrhagic fever (DHF). Dengue infection evolution to severe outcomes is in part, related to innate immunity response. The MBL2 gene encodes for a pathogen recognition pattern molecule, the mannose-binding lectin (MBL). Variant alleles at promoter and structural regions of the MBL2 are related to serum MBL levels and function. Due to the important inflammatory modulation role of MBL, MBL2 polymorphisms could influence dengue progression. Therefore, this study investigated associations of MBL2 polymorphisms and serum MBL levels in patients with dengue. Genotyping of promoter and structural regions of MBL2 was performed by real-time PCR using Taqman® probes in 161 patients presenting DF or DHF outcome. For the serum MBL determination a commercial ELISA kit was used. The variant OO genotype and O allele were associated with DHF (p=0.008 and p=0.009 respectively). Haplotypes correlated to MBL low levels were associated with DHF (p=0.04). Our results support the hypothesis that patients carrying genotypes or haplotypes of low production of MBL would be more susceptible to DHF.

Myeloperoxidase gene polymorphism predicts fibrosis severity in women with hepatitis C

Oxidative stress plays an important role on liver fibrosis progression in the course of hepatitis C virus (HCV) infection. Myeloperoxidase (MPO) is an enzyme released by neutrophils and macrophages, responsible for generating hypochlorous acid and reactive oxygen species (ROS) that may lead to liver injury in HCV infection. On the other hand, antioxidant enzymes such as manganese superoxide dismutase (SOD) controls ROS-mediated damage. The aim of the present study was to investigate the influence of MPO G-463A and SOD2 Ala16Val polymorphisms in the severity of liver fibrosis in individuals with chronic HCV infection. The present study included 270 patients with chronic HCV recruited from the Gastrohepatology Service of the Oswaldo Cruz University Hospital/Liver Institute of Pernambuco (Recife, Northeastern Brazil). All patients underwent liver biopsy, which was classified according METAVIR score. The SNPs were determined by real-time PCR. After multivariate analysis adjustment, the GG genotype of MPO and the presence of metabolic syndrome were independently associated with fibrosis severity in women (P = 0.025 OR 2.25 CI 1.10-4.59 and P = 0.032 OR 2.32 CI 1.07-5.01, respectively). The presence of the GG genotype seems to be a risk factor for fibrosis severity in women with HCV.

Association of Catalase and Glutathione Peroxidase 1 Polymorphisms with Chronic Hepatitis C Outcome.

The hepatic damage caused by hepatitis C virus (HCV) infection is associated with the host immune response and viral regulatory factors. Catalase (CAT) and glutathione peroxidase 1 (GPX1) are antioxidant enzymes located in the peroxisomes and mitochondria, respectively, and are responsible for the control of intracellular hydrogen peroxide levels. Polymorphisms in CAT (C‐262T) and GPX1 (Pro198Leu) are correlated with serum levels and enzyme activity. This study aimed to investigate the association of genetic polymorphisms of CAT C‐262T (rs1001179) and GPX1 Pro198Leu (rs1050450) with different stages of liver fibrosis and development of hepatocellular carcinoma (HCC). This study included 445 patients with chronic hepatitis C, of whom 139 patients had mild fibrosis (F0‐F1), 200 had moderate/severe fibrosis (F2‐F4), and 106 had HCC. Genotyping of SNPs was performed by real‐time PCR using TaqMan probes. The Pro/Pro genotype of GPX1 was significantly associated with fibrosis severity, HCC, Child Pugh score, and BCLC staging. Additionally, patients carrying both CT+TT genotypes in the CAT gene and the Pro/Pro genotype in the GPX1 gene had higher risk for developing moderate/severe fibrosis or HCC (p = 0.009, OR 2.40 and p = 0.002, OR 3.56, respectively). CAT and GPX1 polymorphisms may be implicated in the severity of liver fibrosis and HCC caused by HCV.