Current progress in host innate and adaptive immunity against hepatitis C virus infection

Non-invasive transdermal delivery of biomacromolecules with fluorocarbon-modified chitosan for melanoma immunotherapy and viral vaccines

Transdermal drug delivery has been regarded as an alternative to oral delivery and subcutaneous injection. However, needleless transdermal delivery of biomacromolecules remains a challenge. Herein, a transdermal delivery platform based on biocompatible fluorocarbon modified chitosan (FCS) is developed to achieve highly efficient non-invasive delivery of biomacromolecules including antibodies and antigens. The formed nanocomplexes exhibits effective transdermal penetration ability via both intercellular and transappendageal routes. Non-invasive transdermal delivery of immune checkpoint blockade antibodies induces stronger immune responses for melanoma in female mice and reduces systemic toxicity compared to intravenous injection. Moreover, transdermal delivery of a SARS-CoV-2 vaccine in female mice results in comparable humoral immunity as well as improved cellular immunity and immune memory compared to that achieved with subcutaneous vaccine injection. Additionally, FCS-based protein delivery systems demonstrate transdermal ability for rabbit and porcine skins. Thus, FCS-based transdermal delivery systems may provide a compelling opportunity to overcome the skin barrier for efficient transdermal delivery of bio-therapeutics.

Direct-acting Antiviral-induced Transient Recovery of NK Cells in Early-stage Treatment of Chronic Hepatitis C Patients

BACKGROUND AND AIMS

The rapid clearance of hepatitis C virus induced by direct-acting antivirals (DAAs) affects natural killer (NK) cells, but the reported results are not consistent, and the relative mechanism was unclear. This study focused on the dynamic changes of NK cells during and after DAA treatment and analyzed the reasons.

METHODS

Peripheral blood from 35 chronic hepatitis C patients who were treated with DAAs were collected at baseline and weeks 1, 2, 4, 12, and post-treatment week-12. The frequency, subset, and phenotype of NK cells were assayed by flow cytometry. Lactate dehydrogenase assays were used to evaluate the cytotoxicity of NK cells. Cytokine concentrations were measured with Luminex kits.

RESULTS

All patients achieved a sustained viral response (SVR), and the NK cell frequencies were not changed significantly during DAA therapy. However, the cytotoxicity of NK cells recovered significantly early in week 1, and then continuously decreased below normal levels. The changes of genotypes including NKp30⁺, NKp46⁺, and NKG2A⁺ NK cells were parallel to NK function. The subset of CD56^dim NK cells continuously increased and did not return to normal even at 12 weeks after treatment. Interleukin (IL)-2, IL10, IL15, interferon-gamma, and tumor necrosis factor-alpha all increased after week 4, peaked at the end of therapy, and then exhibited varying degrees of reduction with time.

CONCLUSIONS

DAA treatment led to transient functional recovery of NK cells in the early stage of treatment, and then continuously decreased to below normal levels. Alterations of NK subsets, phenotypes, and the microenvironment may be involved in the changes.

Application of phage display for T-cell receptor discovery

The immune system is tasked to keep our body unharmed and healthy. In the immune system, B- and T-lymphocytes are the two main components working together to stop and eliminate invading threats like virus particles, bacteria, fungi and parasite from attacking our healthy cells. The function of antibodies is relatively more direct in target recognition as compared to T-cell receptors (TCR) which recognizes antigenic peptides being presented on the major histocompatibility complex (MHC). Although phage display has been widely applied for antibody presentation, this is the opposite in the case of TCR. The cell surface TCR is a relatively large and complex molecule, making presentation on phage surfaces challenging. Even so, recombinant versions and modifications have been introduced to allow the growing development of TCR in phage display. In addition, the increasing application of TCR for immunotherapy has made it an important binding motif to be developed by phage display. This review will emphasize on the application of phage display for TCR discovery as well as the engineering aspect of TCR for improved characteristics.

Estimating the transmissibility of hepatitis C: A modelling study in Yichang City, China

Yichang is a city in central China in the Hubei Province. This study aimed to estimate the dynamics of the transmissibility of hepatitis C using a mathematical model and predict the transmissibility of hepatitis C in 2030. Data of hepatitis C cases from 13 counties or districts (cities) in Yichang from 2008 to 2016 were collected. A susceptible-infectious-chronic-recovered (SICR) model was developed to fit the data. The transmissibility of hepatitis C at the counties or districts was calculated based on new infections (including infected or chronically infected cases) reported monthly in the city caused by one infectious individual (MNI). The trend of the MNI was fitted and predicted using 11 models, with the coefficient of determination (R² ) was being used to test the goodness of fit of these models. A total of 3065 cases of hepatitis C were reported in Yichang from 2008 to 2016. The median MNI of Yichang was 0.0768. According to the fitting results and analysis, the trend of transmissibility of hepatitis C in Yichang City conforms with the logarithmic (R²  = 0.918, p < 0.001):MNI = 0.265-0.108 log(t) and exponential (R²  = 0.939, p < 0.001): MNI = 0.344e^(-0.278t) models. Hence, the transmission of hepatitis C virus at the county level has a downward trend. In conclusion, the transmissibility of hepatitis C in Yichang has a downward trend. With the current preventive and control measures in place, the spread of hepatitis C can be controlled.

Genetic Variants in KIR/HLA-C Genes Are Associated With the Susceptibility to HCV Infection in a High-Risk Chinese Population

Background

KIR/HLA-C signaling pathway influences the innate immune response which is the first defense to hepatitis C virus (HCV) infection. The aim of this study was to determine the association between the genetic polymorphisms of KIR/HLA-C genes and the outcomes of HCV infection in a high-risk Chinese population.

Methods

In this case-control study, four single nucleotide polymorphisms (SNPs) of KIR/HLA-C genes (KIR2DS4/KIR2DS1/KIR2DL1 rs35440472, HLA-C rs2308557, HLA-C rs1130838, and HLA-C rs2524094) were genotyped by TaqMan assay among drug users and hemodialysis (HD) patients including 1,378 uninfected control cases, 307 subjects with spontaneous viral clearance, and 217 patients with persistent HCV infection. Bioinformatics analysis was used to functionally annotate the SNPs.

Results

After logistic regression analysis, the rs35440472-A and rs1130838-A alleles were found to be associated with a significantly elevated risk of HCV infection (OR = 1.562, 95% CI: 1.229–1.987, P < 0.001; OR = 2.134, 95% CI: 1.180–3.858, P = 0.012, respectively), which remained significant after Bonferroni correction (0.05/4). The combined effect of their risk alleles and risk genotypes (rs35440472-AA and rs1130838-AA) were linked to the increased risk of HCV infection in a locus-dosage manner (all P_trend < 0.001). Based on the SNPinfo web server, rs35440472 was predicted to be a transcription factor binding site (TFBS) while rs1130838 was predicted to have a splicing (ESE or ESS) function.

Conclusion

KIR2DS4/KIR2DS1/KIR2DL1 rs35440472-A and HLA-C rs1130838-A variants are associated with increased susceptibility to HCV infection in a high-risk Chinese population.

The transmissibility of hepatitis C virus: a modelling study in Xiamen City, China

This study aimed at estimating the transmissibility of hepatitis C. The data for hepatitis C cases were collected in six districts in Xiamen City, China from 2004 to 2018. A population-mixed susceptible-infectious-chronic-recovered (SICR) model was used to fit the data and the parameters of the model were calculated. The basic reproduction number (R₀) and the number of newly transmitted cases by a primary case per month (MNI) were adopted to quantitatively assess the transmissibility of hepatitis C virus (HCV). Eleven curve estimation models were employed to predict the trends of R₀ and MNI in the city. The SICR model fits the reported HCV data well (P < 0.01). The median R₀ of each district in Xiamen is 0.4059. R₀ follows the cubic model curve, the compound curve and the power function curve. The median MNI of each district in Xiamen is 0.0020. MNI follows the cubic model curve, the compound curve and the power function curve. The transmissibility of HCV follows a decreasing trend, which reveals that under the current policy for prevention and control, there would be a high feasibility to eliminate the transmission of HCV in the city.

Genetic variant of RXR involved in the vitamin D metabolic pathway was linked to HCV infection outcomes among a high-risk Chinese population

Genetic variation of related genes in Vitamin D (VD) metabolic pathway played an important role in antiviral immune response and chronic hepatitis C virus (HCV) infection. Retinoid X receptor (RXR) is one of the key genes in the metabolism pathway of VD. This study aims to investigate the effect of single nucleotide polymorphisms (SNPs) in RXR on the outcomes of HCV infection. Three SNPs (RXRɑ-rs4842194, rs1045570 and RXRβ-rs2076310) were genotyped using Sequenom MassARRAY platform in 515 spontaneous clearance subjects, 830 persistent infection subjects, and 1062 uninfected subjects. Multivariate stepwise regression analyss was used to identify the prediction factors for HCV infection outcomes. The USCS Brower and RNAfold web serves were performed to further explore the potential biological functions of positive SNPs. The results of logistic regression analysis after adjusting for age, gender and types of high-risk population showed that subjects with RXRβ rs2076310-T (recessive model: adjusted OR = 1.598, 95%CI = 1.126-2.267, P = 0.009; additive model: adjusted OR = 1.196, 95%CI = 1.011-1.416, P = 0.037) had a significantly increased possibility of HCV infection chronicity. Rs2076310, age, types of high-risk population and aspartate aminotransferase were independent predictors of chronic HCV infection (P < 0.05). And the area under the receiver operating characteristic curve of combined effects of these factors was 0.679. Bioinformatics analysis indicated that rs2076310 could affect the gene expression level by affecting the transcriptional regulatory activity of the corresponding gene region. These findings indicated that genetic variation of RXRβ was associated with the risk of HCV infection chronicity among a high-risk Chinese population.

Canola oilseed- and Escherichia coli- derived hepatitis C virus (HCV) core proteins adjuvanted with oil bodies, induced robust Th1-oriented immune responses in immunized mice

Induction of broad Th1 cellular immune responses and cytokines is crucial characteristics for vaccines against intracellular infections such as hepatitis C virus (HCV). Plants (especially oilseed tissues) and plant-immunomodulators (like oil bodies) offer cost-effective and scalable possibilities for the production of immunologically relevant and safe vaccine antigens and adjuvants, respectively. Herein, we provide data of the murine immunization by transgenic canola oilseed-derived HCV core protein (HCVcp) soluble extract (TSE) and Escherichia coli- derived rHCVcp in combination with Canola oil bodies (oil) compared to that of the Freund's (FA) adjuvant. Mice immunized by TSE+ oil developed both strong humeral (IgG) and Th1-biased cellular responses, manifested by high levels of IFN-γ and lower IgG1/IgG2a ratio and IL-4 secretion. Results of the intracellular cytokine staining indicated that TSE+ oil immunization in mice triggered both CD4⁺ and CD8⁺ T cells to release IFN-γ, while CD4⁺ cells were mostly triggered when FA was used. Analyses by qRT-PCR indicated that a combination of rHCVcp/TSE with oil body induced high levels of IL-10 cytokines compared to that of the FA adjuvant. These characteristics are important properties for the design of an HCV vaccine candidate and indicate the potential of Canola-derived antigen and oil bodies in addressing these concerns.

Risk of Hepatocellular Carcinoma after HCV Clearance by Direct-Acting Antivirals Treatment Predictive Factors and Role of Epigenetics

Direct-acting antivirals (DAAs) induce a rapid virologic response (SVR) in up to 99% of chronic hepatitis C patients. The role of SVR by DAAs on the incidence or recurrence of hepatocellular carcinoma (HCC) is still a matter of debate, although it is known that SVR does not eliminate the risk of HCC. In this review, we made an updated analysis of the literature data on the impact of SVR by DAAs on the risk of HCC as well as an assessment of risk factors and the role of epigenetics. Data showed that SVR has no impact on the occurrence of HCC in the short–medium term but reduces the risk of HCC in the medium–long term. A direct role of DAAs in the development of HCC has not been demonstrated, while the hypothesis of a reduction in immune surveillance in response to the rapid clearance of HCV and changes in the cytokine pattern influencing early carcinogenesis remains to be further elucidated. HCV induces epigenetic alterations such as modifications of the histone tail and DNA methylation, which are risk factors for HCC, and such changes are maintained after HCV clearance. Future epigenetic studies could lead to identify useful biomarkers and therapeutic targets. Cirrhosis has been identified as a risk factor for HCC, particularly if associated with high liver stiffness and α-fetoprotein values, diabetes and the male sex. Currently, considering the high number and health cost to follow subjects’ post-HCV clearance by DAAs, it is mandatory to identify those at high risk of HCC to optimize management.

Association between Hepatitis C Virus Viremia and the rs12979860, rs2228145 and rs1800795 SNP (CT/AC/GG) Genotype in Saudi Kidney Transplant Recipients

Background:

Hepatitis C virus (HCV) is a major health problem, particularly in high-risk groups such as kidney transplant recipients, where it can adversely affect graft survival and increase the relative risk for mortality. Recently, the role of genetic variation among HCV patients in determining the outcome of infections has been under investigation.

Objective:

To investigate the association of single-nucleotide polymorphisms (SNPs) rs12979860 (located within the interleukin-28B locus), rs2228145 (interleukin-6 receptor) and rs1800795 (interleukin-6 promoter) with HCV viremia in renal transplant patients.

Materials and Methods:

In this analytical cross-sectional study, 149 kidney transplant recipients, 82 males (median age: 41 years) and 67 females (median age: 45 years), were screened for HCV RNA in blood using real-time polymerase chain reaction and genotyped by sequencing (rs12979860) and restriction fragment length polymorphism (rs2228145 and rs1800795).

Results:

HCV RNA was detected in 17 (11.41%) of the 149 patients. There was no statistically significant association between the studied SNPs and HCV viremia. However, a combination of the CT/AC/GG genotype was significantly associated with HCV viremia (odds ratio: 5.4). The genotype AA of rs2228145 in the IL-6 receptor was associated with viremia levels of >10⁵ copies/ml (odds ratio: 5.96).

Conclusion:

To the best of the authors' knowledge, this is the first study that has shown that the CT/AC/GG genotype has an impact on HCV viremia in kidney transplant patients. Therefore, such SNP genotypes may potentially be used to identify transplant patients at risk of HCV infection.

Impact of CYP2R1, CYP27A1 and CYP27B1 genetic polymorphisms controlling vitamin D metabolism on susceptibility to hepatitis C virus infection in a high-risk Chinese population

CYP27A1, CYP2R1 and CYP27B1 hydroxylases are involved in the synthesis of 1, 25-hydroxyvitamin D₃, which plays a role in the immune regulation and pathogenesis of hepatitis C virus (HCV) infection. The aim of the present study was to investigate the relationships between polymorphisms in vitamin D pathway genes and HCV infection outcomes in a Chinese population. Nine single-nucleotide polymorphisms (SNPs) of CYP27A1, CYP2R1 and CYP27B1 were genotyped in a high-risk Chinese population. The distributions of these SNPs were compared among groups with different outcomes of HCV infection, including 863 cases of persistent HCV infection, 524 cases of spontaneous clearance, and 1079 uninfected controls. The results showed that the CYP2R1 rs12794714-G, rs10741657-A, rs1562902-C, and rs10766197-G alleles were significantly associated with increased susceptibility to HCV infection (all P_FDR < 0.05, in additive/dominant models), and the combined effect of the four unfavorable alleles was related to an elevated risk of HCV infection in a locus-dosage manner (P_trend = 0.008). Moreover, haplotype analysis suggested that, compared with the most frequent haplotype (A_rs12794714G_rs10741657T_rs1562902A_rs10766197), the haplotype containing four unfavorable alleles, GACG, was associated with a higher risk of HCV infection. The results of our study suggest that genetic variants in CYP2R1 may be biomarkers for predicting the susceptibility to HCV infection in the Chinese population.

Incidence and risk factors of early HCC occurrence in HCV patients treated with direct acting antivirals: a prospective multicentre study

BACKGROUND

An unexpected increased HCC recurrence and occurrence rate among HCV patients treated with direct acting antivirals combination has been reported. Aim of the study was the evaluation of early HCC occurrence rate and its risk factors in a HCV infected population, treated with direct-acting-antivirals.

METHODS

According to the Italian ministerial guidelines for direct-acting-antivirals treatment, 1022 consecutive HCV patients treated with direct-acting-antivirals were enrolled. Patients either with active HCC at imaging or history of previous treated HCC, HBV or HIV co-infection, or liver transplant recipients were excluded. The SVR, defined as the persistent absence of detectable serum HCV-RNA 12 weeks after the end of treatment (SVR12), was assessed for all enrolled patients. Abdominal ultrasound was performed before starting antiviral therapy, and repeated every 6 months. HCC was diagnosed according to the international guidelines. Patients showing either nodular patterns suggestive of HCC or with uncertain dynamic vascular behaviour were excluded from a further follow-up.

RESULTS

Nine hundred and eighty-five patients completed the 48 weeks follow-up after the end of treatment. A Sofosbuvir-based regimen was administered in the 74.9% of patients, among whom, the 71.6% underwent a simultaneous Ribavirin administration. A sustained virological response at 12 weeks off treatment was documented in 966 patients (98.2%). During the post treatment follow-up HCC was detected in 35 patients, with a cumulative incidence rate of the 3.55%. At multivariate analysis, four variables resulted independently associated with HCC development, both in a cirrhosis based and a class B Child based model, respectively: cirrhosis/class B Child, therapeutic schedule including Sofosbuvir without Ribavirin, liver stiffness values, male gender and presence of diabetes. A multivariate analysis performed on Child A cirrhotic patients, showed that Sofosbuvir based therapeutic treatment without Ribavirin had a HCC occurrence 5.7 higher than Ribavirin-based schedules with or without Sofosbuvir (p < 0.0001, OR: 5.686, 95% CI 2.455-13.169).

CONCLUSIONS

Our data suggest that early HCC occurrence appears more frequently related to Sofosbuvir-based therapy without Ribavirin which, indeed, seems to play a protective role on HCC onset. Therefore, a careful follow-up should be mandatory, especially in those regimens including Sofosbuvir without Ribavirin.

A non-pathogenic Leishmania tarentolae vector based- HCV polytope DNA vaccine elicits potent and long lasting Th1 and CTL responses in BALB/c mice model

Despite successful anti-viral (DAAs) treatment of Hepatitis C virus (HCV) infection, recent data indicated the need for an effective vaccine. Preexisting anti-vector immunity is an obstacle for application of live vectors for antigen delivery and development of effective T-cell based HCV vaccines. Herein, we report construction of recombinant Leishmania tarentolae, a lizard (non-human) parasite, expressing an HCV polytope DNA, PT-NT(gp96), encoding for several immunogenic HCV epitopes and evaluation of its immunogenicity in three different prime/boost immunization groups (G) of BALB/c mice. Homologous prime/boost immunization by L.tarentolae-PT-NT(gp96) either with or without CpG (G1 and G2 respectively) and heterologous immunization with a PT-NT(gp96) encoding-pCDNA plasmid followed by L.tarentolae-PT-NT (G3) was undertaken. Immune responses were measured three and nine weeks (W) post immunization. Splenocytes (cultured with antigen-stimulant) of mice in G1 showed the highest percentage of specific CTL-cytolytic activity compared to G2 and G3 at both short (W3:70.98% versus 41.29% and 13.12%) and long (W9: 50% versus 24.5% and 20%) term periods, accompanied with high levels of secreted IFN-γ. Comparison of IFN-γ, IL-4, IL-17 and TNF-α cytokines levels obtained from the supernatant of antigen-stimulated splenocytes as well as antibodies level (as IgG1/IgG2a ratio; obtained from sera of immunized mice) indicated higher Th1 oriented responses for G1, G2 groups and balanced Th1-Th17 for G3. Results indicated the potential of L.tarentolae (+CpG), as a non-pathogenic live vaccine vector, for delivery and enhancement of immune responses against HCV-polytope antigens.

Stability of β-turn in LaR2C-N7 peptide for its translation-inhibitory activity against hepatitis C viral infection: A molecular dynamics study

Hepatitis C virus (HCV) requires an essential host factor, human La protein, for its translation and replication activity. Earlier, it was demonstrated that a 24-mer synthetic peptide (LaR2C) encompassing residues 112 to 184 of the natural human La protein interacts with the HCV internal ribosome entry site (IRES) and inhibits translation. Interestingly, a shorter version of the same LaR2C peptide, LaR2C-N7, containing residues 174 to 180 (KYKETDL), with a unique β-turn secondary structure, is sufficient to inhibit IRES mediated translation of HCV. Hence, it is imperative to understand the role of each amino acid of this heptapeptide towards β-turn formation which will then help in designing potential drugs against HCV infection. Here, we use Nanoscale Molecular Dynamics (NAMD) simulation to investigate the factors modulating its β-turn formation and stability. Using 100 ns simulation paradigms, we find that the peptide populated the type 1 β-turn conformation in its free form in solution. However, simulation of the single-site mutants of the heptapeptide revealed that none of the 7 mutants retained the β-turn conformation with sufficient stability. We observed that the β-turn was stabilized mainly by the side chain interaction, salt-bridge and weak hydrogen bonds between K3 and D6 residues. Y2, K1 and K3 sites upon mutation heavily destabilized the β-turn when compared to alteration at the E4 and T5 sites which would then drastically reduce its HCV RNA IRES binding capabilities. Taken together, our results provide a basis for designing peptidomimetics as potential anti-HCV drug candidates.

Genetic variants in RIG-I-like receptor influences HCV clearance in Chinese Han population

Human innate immune plays an essential role in the spontaneous clearance of acute infection and therapy of HCV. We investigated whether the SNPs in retinoic acid-inducible gene I-like receptor family were associated with HCV spontaneous clearance and response to treatment. To evaluate the clinical value of DDX58 rs3824456, rs10813831 and rs10738889 genotypes on HCV spontaneous clearance and treatment response in Chinese Han population, we genotyped 1001 HCV persistent infectors, 599 participants with HCV natural clearance and 354 patients with PEGylated interferon-α and ribavirin (PEG IFN-α/RBV) treatment. People carrying rs10813831-G allele genotype were more liable to achieve spontaneous clearance than the carriage of the T allele (dominant model: adjusted OR 1.35, 95% CI 1.08-1.71, P = 0.008). In rs10738889, the rate of persistent infection was significantly lower in patients with the TC genotype compared to those with TT genotype (dominant model: adjusted OR 1.36, 95% CI 1.06-1.74, P = 0.015). Multivariate stepwise analysis indicated that rs10738889, age, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were independent predictors for HCV spontaneous clearance. However, there were no significant differences in the three selection SNPs between the non-SVR group and the SVR group. These results suggest the DDX58 rs10813831 and rs10738889 are associated with spontaneous clearance of HCV, which may be identified as a predictive marker in the Chinese Han population of HCV.

Hepatitis C virus direct-acting antivirals therapy impacts on extracellular vesicles microRNAs content and on their immunomodulating properties

BACKGROUND & AIMS

Hepatitis C virus (HCV) infection is known to cause major alterations in the cross-talk between hepatic and immune cells thus contributing to the liver disease pathogenesis. Extracellular vesicles have been proved to act as major players in cell-cell communication, and their cargo changes in relation to pathophysiological states. The aim of this study was to evaluate the effects of chronic HCV infection and direct-acting antivirals (DAA) on exosome-delivered microRNAs and on their ability to modulate the innate immune response.

METHODS

Exosomes isolated from the plasma of healthy donors and naïve, viremic HCV patients before and after DAA treatment have been compared for their microRNAs cargo by quantitative polymerase chain reaction. Functional assays with peripheral blood cells from healthy donors were performed to assess exosome-mediated immune responses.

RESULTS

MicroRNAs associated with HCV-related immunopathogenesis which were found to be enriched in exosomes of HCV viremic patients (in particular, miR-122-5p, miR-222-3p, miR-146a, miR-150-5p, miR-30c, miR-378a-3p and miR-20a-5p) were markedly reduced by DAA therapy. This exosome-microRNA cargo modulation parallels changes in their immunomodulatory properties in ex vivo experiments. Exosomes from HCV patients inhibit NK degranulation activity and this effect correlates with miR-122-5p or miR-222-3p levels.

CONCLUSIONS

Enrichment of immunomodulatory microRNAs in exosomes of HCV patients was correlated with their inhibitory activity on innate immune cells function. Direct-acting antivirals (DAA) treatment was observed to revert both microRNA content and functional profiles of systemic exosomes towards those of healthy donors. Exosome-associated microRNAs may provide valuable biomarkers to monitor immune response recovery.

Tolerable and curable treatment in HIV/HCV co-infected patients using anti-HCV direct antiviral agents: a real-world observation in China

OBJECTIVE

No brand direct-acting antiviral agents (DAAs) are available for treatment of HIV-1/HCV co-infected patients in China. This study aimed to observe the therapeutic efficacy and safety of generic DAAs for affected Chinese patients.

DESIGN

Real-world setting to elucidate whether DAAs were tolerated and effective in HIV-1/HCV co-infected patients.

METHODS

176 HIV-1/HCV co-infected patients received anti-HCV DAA treatment together with ART regimens for HIV infection. Among the 176 patients, 99 patients were treated with SOF + DCV ± RBV, 60 patients were treated with SOF + LDV ± RBV, and 17 patients received SOF + RBV ± Peg-IFN regimens, for 12 or 24 weeks, respectively. The primary endpoint was undetectable HCV RNA 12 weeks after therapy was completed (SVR12). Data pertaining to safety and adverse events were analyzed.

RESULTS

151/176 HIV-1/HCV co-infected patients finished the treatment and 12-week follow-up. SVR12 for the patients treated with regimens of SOF + DCV, SOF + DCV+RBV, SOF + Peg-IFN+RBV, SOF + RBV, SOF + LDV, and SOF + LDV+RBV for 12 or 24 weeks was 100% (75/75), 100% (11/11), 100% (14/14), 100% (2/2), 95.2% (40/42), and 100% (7/7), respectively. HIV-1/HCV co-infected patients with liver cirrhosis achieved well SRV12. Notably, there was no significant difference in adverse effects among patients with different baseline CD4⁺ T-cell count in those who received DAA regimens with or without Peg-IFN and RBV.

CONCLUSION

We showed generic SOF + DCV and SOF + LDV regimens were well tolerated and with high efficiency. Patient's baseline CD4⁺ T-cell count did not exhibit significant difference in adverse effects.

Direct-acting antiviral treatment of acute hepatitis C virus infections

INTRODUCTION

Hepatitis C contributes to significant morbidity and mortality worldwide. AHCV is defined as documented infection within 6 months of exposure. Treating acute hepatitis C virus (AHCV) with direct-acting antiviral agents in persons who inject drugs, HIV-positive men who have sex with men, and patients who acquire HCV nosocomially can contribute to the elimination of disease globally, preclude the morbidity and mortality of chronic disease, and prevent further transmission. Areas covered: In this review, we describe the epidemiology of AHCV, its natural history, the considerations involved in the decision of whether to treat AHCV, and the most current DAA therapy guidelines. PubMed was queried using key words and bibliographies were evaluated for relevant articles. Expert commentary: Despite the obvious benefits of AHCV treatment, clinical management is limited by the ability to identify asymptomatic cases and the absence of fully supported guidelines. However, clinical research is advancing and identifying specific regimens, decreasing treatment durations, and creating strategies to target at risk groups and screen for AHCV.

Different core-specific T cell subsets are expanded in chronic hepatitis C with advanced liver disease

Chronic hepatitis C (CHC) is frequently related to liver fibrosis, and several studies have suggested that the immunological activity of HCV antigens contributes to hepatic damage. In the present study, among structural and non-structural HCV antigens, elevatedIL-1β, IL-6, IL-17 levels were secreted by PBMC cultures obtained from CHC patients following stimulation with core antigen. Moreover, the percentage of core-specific IL-6⁺IL-17⁺(CD4⁺ and CD8⁺) T cells was significantly higher in patients with worsehepatic lesions, determined on the Metavir scale. When compared with healthy subjects, the percentage of circulating Treg cells was elevated in CHC patients, mainly among those with advanced liver fibrosis. Nevertheless, in this last group of patients, the proportion of CD39⁺ Treg subsets was very low. Finally, the percentage of senescent (CD57⁺ CD28^-) and exhausted (PD-1⁺CD28⁺) core-specific T cells in CHC patients was also found to be a result of fibrotic hepatic status. In summary, imbalances between different core-specific T cell subsets are associated with liver fibrosis severity.

Proprotein convertase subtilisin/kexin type 9 inhibits interferon β expression through interacting with ATF-2

Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates lipid metabolism. A mutual interplay of lipid homeostasis and innate immune system has been increasingly recognized. We, therefore, studied the effect of PCSK9 on interferon (IFN) β expression. We show that PCSK9 decreases IFNβ promoter/enhancer activity, mRNA and protein levels, and its downstream 2',5'-oligoadenylate synthetase-1 mRNA level. ProPCSK9, but not the cleaved PCSK9, down-regulates IFNβ promoter/enhancer activity. Moreover, PCSK9 decreases IFNβ promoter/enhancer activity through the positive regulatory domain IV region where the activating transcription factor-2 (ATF-2)/c-Jun heterodimer binds. Mechanistically, we demonstrate an interaction between PCSK9 and ATF-2, which reduces ATF-2/c-Jun dimerization and ATF-2/c-Jun binding to the IFNβ enhancer. This novel function of PCSK9 should have important implications in optimizing the clinical use of PCSK9 inhibitors.