HDV can constrain HBV genetic evolution in hbsag: Implications for the identification of innovative pharmacological targets

Chronic HBV + HDV infection is associated with greater risk of liver fibrosis, earlier hepatic decompensation, and liver cirrhosis hepatocellular carcinoma compared to HBV mono-infection. However, to-date no direct anti-HDV drugs are available in clinical practice. Here, we identified conserved and variable regions in HBsAg and HDAg domains in HBV + HDV infection, a critical finding for the design of innovative therapeutic agents. The extent of amino-acid variability was measured by Shannon-Entropy (Sn) in HBsAg genotype-D sequences from 31 HBV + HDV infected and 62 HBV mono-infected patients (comparable for demographics and virological-parameters), and in 47 HDAg genotype-1 sequences. Positions with Sn = 0 were defined as conserved. The percentage of conserved HBsAg-positions was significantly higher in HBV + HDV infection than HBV mono-infection (p = 0.001). Results were confirmed after stratification for HBeAg-status and patients’ age. A Sn = 0 at specific positions in the C-terminus HBsAg were correlated with higher HDV-RNA, suggesting that conservation of these positions can preserve HDV-fitness. Conversely, HDAg was characterized by a lower percentage of conserved-residues than HBsAg (p < 0.001), indicating higher functional plasticity. Furthermore, specific HDAg-mutations were significantly correlated with higher HDV-RNA, suggesting a role in conferring HDV replicative-advantage. Among HDAg-domains, only the virus-assembly signal exhibited a high genetic conservation (75% of conserved-residues). In conclusion, HDV can constrain HBsAg genetic evolution to preserve its fitness. The identification of conserved regions in HDAg poses the basis for designing innovative targets against HDV-infection

Improvement of ALT decay kinetics by all-oral HCV treatment: Role of NS5A inhibitors and differences with IFN-based regimens

Background: Intracellular HCV-RNA reduction is a proposed mechanism of action of direct-acting antivirals (DAAs), alternative to hepatocytes elimination by pegylated-interferon plus ribavirin (PR). We modeled ALT and HCV-RNA kinetics in cirrhotic patients treated with currently-used all-DAA combinations to evaluate their mode of action and cytotoxicity compared with telaprevir (TVR)+PR. Study design: Mathematical modeling of ALT and HCV-RNA kinetics was performed in 111 HCV-1 cirrhotic patients, 81 treated with all-DAA regimens and 30 with TVR+PR. Kinetic-models and Cox-analysis were used to assess determinants of ALT-decay and normalization. Results: HCV-RNA kinetics was biphasic, reflecting a mean effectiveness in blocking viral production &gt;99.8%. The first-phase of viral-decline was faster in patients receiving NS5A-inhibitors compared to TVR+PR or sofosbuvir+simeprevir (p&lt;0.001), reflecting higher efficacy in blocking assembly/secretion. The second-phase, noted \u3b4 and attributed to infected-cell loss, was faster in patients receiving TVR+PR or sofosbuvir+simeprevir compared to NS5A-inhibitors (0.27 vs 0.21 d-1, respectively, p = 0.0012). In contrast the rate of ALT-normalization, noted \u3bb, was slower in patients receiving TVR+PR or sofosbuvir+simeprevir compared to NS5A-inhibitors (0.17 vs 0.27 d-1, respectively, p&lt;0.001). There was no significant association between the second-phase of viral-decline and ALT normalization rate and, for a given level of viral reduction, ALT-normalization was more profound in patients receiving DAA, and NS5A in particular, than TVR+PR. Conclusions: Our data support a process of HCV-clearance by all-DAA regimens potentiated by NS5A-inhibitor, and less relying upon hepatocyte death than IFN-containing regimens. This may underline a process of "cell-cure" by DAAs, leading to a fast improvement of liver homeostasis

DECLINE OF PREVALENCE OF RESISTANCE ASSOCIATED SUBSTITUTIONS TO NS3 AND NS5A INHIBITORS AT DAA- FAILURE IN HEPATITIS C VIRUS IN ITALY OVER THE YEARS 2015 TO 2018

Background: A minority of patients fails to eliminate HCV and resistance-associated substitutions (RASs) are commonly detected at failure of interferon-free DAA regimens . Methods: Within the Italian network VIRONET-C, the prevalence of NS3/NS5A/NS5B RASs was retrospectively evaluated in patients who failed an EASL recommended DAA-regimen in 2015-2018 . The geno2pheno system and Sorbo MC et al. Drug Resistance Updates 2018 were used to infer HCV- genotype/subtype and predict drug resistance . The changes in prevalence of RASs over time were evaluated by chi-square test for trend, predictors of RASs at failure were analysed by logistic regression . Results: We included 386 HCV infected patients: 75% males, median age was 56 years (IQR 52-61), metavir fibrosis stage F4 in 76%; 106 (28%) were treatment- experienced: 91 (86%) with IFN-based treatments, 26 (25%) with DAAs. Patients with HIV and HBV coinfection were 10% (33/317) and 8% (6/72), respectively. HCV genotype was 1b in 122 pts (32%), 3 in 109 (28%), 1a in 97 (25%), 4 in 37 (10%), 2 in 21 (5%). DAA regimens were: LDV/SOF in 115 (30%), DCV/SOF in 103 (27%), 3D in 83 (21%), EBR/GRZ in 32 (8%), VEL/SOF in 29 (7%), GLE/PIB in 18 (5%) and 2D in 6 (2%); ribavirin was administered in 123 (32%) . The NS5A fasta-sequence was available for all patients, NS5B for 361 (94%), NS3 for 365 (95%) . According to the DAA failed the prevalence of any RASs was 90%, namely 80/135 (59%) in NS3, 313/359 (87%) in NS5A, 114/286 (40%) in NS5B . The prevalence of any RASs significantly declined from 2015 to 2018 (93% vs 70%, p=0.004): NS5A RASs from 90% to 72% (p=0 .29), NS3 RASs from 74% to 18% (p&lt;0 .001), while NS5B RASs remained stable . Independent predictors of any RASs included advanced fibrosis (AOR 6.1, CI 95% 1.8-20.3, p=0 .004) and genotype (G2 vs G1a AOR 0 .03, CI 95% 0 .002- 0 .31, p=0 .004; G3 vs G1a AOR 0 .08, CI 95% 0 .01-0 .62, p=0 .02; G4 vs G1a AOR 0 .05, CI 95% 0 .006-0 .46, p=0 .008), after adjusting for age, previous HCV treatment and year of genotype . Notably, full activity was predicted for GLE/PIB in 75% of cases and for at least two components of VEL/SOF/VOX in 53% of cases, no case with full-resistance to either regimen was found . Conclusion: Despite decreasing prevalence over the years, RASs remain common at virological failure of DAA treatment, particularly in patients with the highest grade of liver fibrosis. The identification of RASs after failure could play a crucial role in optimizing retreatment strategies

Genetic determinants in a critical domain of ns5a correlate with hepatocellular carcinoma in cirrhotic patients infected with hcv genotype 1b

HCV is an important cause of hepatocellular carcinoma (HCC). HCV NS5A domain‐1 interacts with cellular proteins inducing pro‐oncogenic pathways. Thus, we explore genetic variations in NS5A domain‐1 and their association with HCC, by analyzing 188 NS5A sequences from HCV genotype‐1b infected DAA‐naïve cirrhotic patients: 34 with HCC and 154 without HCC. Specific NS5A mutations significantly correlate with HCC: S3T (8.8% vs. 1.3%, p = 0.01), T122M (8.8% vs. 0.0%, p &lt; 0.001), M133I (20.6% vs. 3.9%, p &lt; 0.001), and Q181E (11.8% vs. 0.6%, p &lt; 0.001). By multivariable analysis, the presence of &gt;1 of them independently correlates with HCC (OR (95%CI): 21.8 (5.7–82.3); p &lt; 0.001). Focusing on HCC‐group, the presence of these mutations correlates with higher viremia (median (IQR): 5.7 (5.4–6.2) log IU/mL vs. 5.3 (4.4–5.6) log IU/mL, p = 0.02) and lower ALT (35 (30–71) vs. 83 (48–108) U/L, p = 0.004), suggesting a role in enhancing viral fitness without affecting necroinflammation. Notably, these mutations reside in NS5A regions known to interact with cellular proteins crucial for cell‐cycle regulation (p53, p85‐PIK3, and β‐ catenin), and introduce additional phosphorylation sites, a phenomenon known to ameliorate NS5A interaction with cellular proteins. Overall, these results provide a focus for further investigations on molecular bases of HCV‐mediated oncogenesis. The role of these NS5A domain‐1 mutations in triggering pro‐oncogenic stimuli that can persist also despite achievement of sustained virological response deserves further investigation

Correlation of serum aminotransferases with HCV RNA levels and histological findings in patients with chronic hepatitis C: the role of serum aspartate transaminase in the evaluation of disease progression

Objectives To investigate whether HCV RNA levels can be considered to be predictors of hepatocellular injury in patients with chronic hepatitis C, and whether aminotransferase levels are markers of liver damage. Methods We performed a retrospective study on 112 patients with chronic hepatitis C. For each patient, we considered the baseline alanine aminotransferase (ALT) and serum aspartate transaminase (AST) levels, baseline HCV RNA, HCV genotype, histological evaluation and the mean aminotransferase levels measured in the 6 months following liver biopsy. Results We found a statistically significant correlation between HCV RNA and aminotransferase levels measured during the follow-up (AST: r=0.24, P =0.01; ALT: r=0.27, P=0.004). We also observed a statistically significant correlation between HCV RNA levels and histological activity index (HAI) (r=0.25, P=0.008), as well as between the HAI and both baseline AST (r=0.34, P=0.0002) and ALT levels (r=0.23, P=0.01). These findings were confirmed by the mean aminotransferase values during follow-up. In the regression analysis, the fibrosis score was significantly and independently associated with baseline AST and ALT values. Conclusions Our results demonstrate a statistically significant correlation of aminotransferase values with the histological parameters, and an even stronger correlation with the AST values. Our study therefore suggests that aminotransferase values, especially AST, may correlate with liver damage

Development of hepatotoxicity in HIV patients switching at least one protease inhibitor

In order to evaluate the occurrence of hepatotoxicity in patients treated with antiretroviral therapy (ART) who switch protease inhibitor (PI), and the role of viral hepatitis in its development, we performed a retrospective study on 182 HIV patients treated with ART for 24 months. The presence of hepatitis viruses and alanine transaminase levels were evaluated. Hepatotoxicity developed in a low number of subjects without co-infection, but was significantly higher in co-infected patients (14/51 versus 62/131, P = 0.01). Ritonavir was associated with higher rates of severe hepatotoxicity in the co-infected group. Patients presenting any problems related to ART, including the development of hepatotoxicity, continued therapy by switching PI. The occurrence of hepatotoxicity with second/third choice PIs, including ritonavir, remained stable. Our results suggest that switching PI does not increase the occurrence of drug-related liver toxicity

Undetectable phospho-STAT1 in peripheral blood mononuclear cells from patients with chronic hepatitis C who do not respond to interferon-alpha therapy

SUMMARY. The a-defensin genes promoter regions contain a putative nuclear factors of activated T cells (NFAT)-binding site and it is known that hepatitis C virus (HCV) core protein activates the interleukin (IL)-2 gene transcription through the NFAT pathway. The aims of this study were to investigate if HCV affects the a-defensin expression in peripheral human mononuclear cells (PBMCs) and to evaluate the existence of a correlation between a-defensins and liver damage in patients with chronic hepatitis C. Ninety patients with chronic hepatitis C, 30 with chronic hepatitis B and 25 healthy controls were enrolled. a-Defensins were identified and quantified in PBMCs by mass spectrometry, enzymelinked immunosorbent assay, antibacterial activity and mRNA levels. PBMCs from three patients and controls were stimulated with HCV core protein, hepatitis B virus core antigen and the a-defensin mRNAs level was quantified. We found that HCV core protein activates in vitro the a-defensin transcription. a-Defensin levels in patients with chronic hepatitis C (mean ± SD ¼ 1.103 ± 0.765 ng/106 cells), chronic hepatitis B (0.53 ± 0.15) and healthy controls (0.217 ± 0.09) resulted significantly different (P < 0.001). In patients with chronic hepatitis C, the a-defensin levels and antibacterial activity correlate with the liver fibrosis. Our data suggest that HCV induces a-defensin expression. The high linear correlation of a-defensin levels with advancing fibrosis makes the measure of these peptides a reliable marker to evaluate fibrosis stage. Keywords: a-defensin, chronic hepatitis, hepatitis C vir