A multiepitope peptide vaccine against HCV stimulates neutralizing humoral and persistent cellular responses in mice

BACKGROUND

Although DAAs hold promise to significantly reduce rates of chronic HCV infections, its eradication still requires development of an effective vaccine. Prolonged T cell responses and cross neutralizing antibodies are ideal for vaccination against the infection. We aimed to design and synthesize a 6 multi epitope peptide vaccine candidate and provide evidence for production of extended cellular and neutralizing Abs in mice.

METHODS

Six peptides derived from conserved epitopes in E1, E2 (n = 2),NS4B, NS5A and NS5B were designed, synthesized in a multiple antigenic peptide (MAP) form and administered w/o adjuvant to BALB/c mice as HCVp6-MAP at doses ranging from 800 ng to 16 μg. Humoral responses to structural epitopes were assayed by ELISA at different times after injection. ELISpot assay was used to evaluate IFN ɣ producing CD4+/ CD8+ T- lymphocytes at extended durations i.e. > 20 weeks. Viral neutralization by mice sera was tested for genotypes 2a (JFH1) and a chimeric 2a/4a virus (ED43/JFH1) in HCVcc culture.

RESULTS

HCVp6-MAP confers potent viral neutralization and specific cellular responses at > 1600 ng/ animal for at least 20 weeks.

CONCLUSION

We report on a promising anti HCV vaccine for future studies on permissive hosts and in clinical trials.

The Impact of COVID-19 on Liver Injury

The current coronavirus disease outbreak of 2019 (COVID-19) has led to a global pandemic. The principal cause of mortality in COVID-19 is represented lung injury with the development of acute respiratory distress syndrome (ARDS). In patients with COVID-19 infection, liver injury or liver dysfunction has been reported. It may be associated with the general severity of the disease and serve as a prognostic factor for ARDS development. In COVID-19, the spectrum of liver damage may range from direct SARS-CoV-2 viral proteins, inflammatory processes, hypoxemia, the antiviral drugs induced hepatic injury and the presence of the preexisting liver disease. We highlight in this review important topics such as the epidemiological features, potential causes of liver injury, and the strategies for management and prevention of hepatic injury in COVID-19 patients.

Dysregulation of fibrosis related genes in HCV induced liver disease

BACKGROUND

Liver fibrosis results from a wound healing response to chronic injury, which leads to excessive matrix deposition. Genome wide association studies have showen transcriptional dysregulation in mild and severe liver fibrosis. Recent studies suggested that genetic markers may be able to define the exact stage of liver fibrosis.

AIM

To define genes or genetic pathways that could serve as markers for staging or as therapeutic targets to halt progression of liver fibrosis.

METHODS

The study was performed on 105 treatment naïve HCV genotype 4 infected patients [F0-F2, n = 56; F3-F4, n = 49] and 16 healthy subjects. The study included PCR array on 84 fibrosis related genes followed by customization of a smaller array consisting of 11 genes that were designed on the bases of results obtained from the larger array. Genes that displayed significant dysregulation at mRNA levels were validated at protein levels.

RESULTS AND DISCUSSION

Two major pathways exhibited high dysregulation in early fibrosis as compared with controls or when compared with late fibrosis, these were the TGFβ - related pathway genes and Matrix - deposition associated genes. Hepatic stellate cell (HSC) activators i.e. TGFβ pathway genes [TGFβ1, 2 and 3, their receptors TGFβR1 and 2, signaling molecules SMAD genes and PDGF growth factors] were considerably over-expressed at transcriptional levels as early as F0, whereas expression of their inhibitor TGIF1 was simultaneously down regulated. Matrix proteins including collagen and MMPs were upregulated in early fibrosis whereas tissue inhibitors TIMPs 1 and 2 began over expression in late fibrosis. Expression at protein levels was concordant with RNA data excluding dysregulation at post transcriptional levels.

CONCLUSION

Since these 2 gene sets are closely interrelated regarding HSC activation and proliferation, we assume that the current findings suggest that they are favorable targets to further search for stage specific markers.

Correlation between IL28B/TLR4 genetic variants and HCC development with/without DAAs treatment in chronic HCV patients

In Egypt, Sofosbuvir (SOF) in combination with Dataclasvir (DCV) is the broadly used DAAs with excellent therapeutic profile. This study is designed to explore the relation between IL28B/TLR4 genetic variants and each of the followings; HCC development post SOF/DCV treatment, progression to HCC in naïve patients and SOF/DCV therapy outcome. A total of 493 blood samples were collected (controls (n = 70); HCV patients treated with SOF/DCV (n = 252) of whom 65 patients developed HCC, 187 patients didn't develop HCC (125 responders, 62 relapsers); naïve HCV patients (n = 171) had early (n = 48), late liver fibrosis (n = 21) and HCC (n = 102)). Both SNPs were genotyped using a TaqMan 5' allelic discrimination assay. At IL28B rs12979860 SNP, the C allele was significantly correlating with the response rate more than T allele (OR 1.9, 95% CI 1.29-2.9, p = 0.004), while at TLR4 rs4986791 SNP, no association was found (OR 6.5, 95% 0.57-75.28, p = 0.09). Both SNPs couldn't detect the probability for HCC emergence after treatment. In naïve patients, the protective alleles were detected in their lowest frequency in HCC patients (p = 0.1, for rs12979860 and, p = 0.001 for rs4986791). SOF/DCV combination improved SVR rates in HCV genotype 4a infected patients regardless of IL28B genotype, with the best rates in those lacking the T allele.

Recipient interleukin 6 gene polymorphism and expression predict HCV recurrence post liver transplantation

BACKGROUND

Liver transplantation (LTX)is a lifesaving- effective protocol for patients suffering end stage liver disease (ESLD) and its complications post HCV infection. Recurrence of disease is a frequent clinical complication that is observed in patients undergoing LTX. Cytokines play a central role in the immunological events occurring after the surgery.

METHODS

Using Allelic Discrimination PCR, the allelic variation G174C of IL-6 gene was investigated. The abundance of IL6- mRNA and plasma IL6 cytokine levels were evaluated by using qRT-PCR in peripheral blood mononuclear cells (PBMCs) and enzyme-linked immunosorbent assay (ELISA) respectively in 76 liver transplant recipients recruited from Al Sahel teaching hospital, Ministry of Health and Population Cairo Egypt within the period between June 2015 and October 2017.

RESULTS

The frequencies of IL-6 GG genotype and the G allele were significantly detected more in LTX recipients who experienced HCV recurrence versus those who did not suffer recurrence when compared to healthy controls (P = 0.001) and (P = 0.006), respectively. On the contrary, levels of IL-6 related transcripts in PBMC's of recurrent patients were indifferent from non-recurrent patients and healthy controls (P ≥ 0.124). Interestingly, the circulating IL-6 protein in plasma was significantly elevated in recurrent as compared to the non-recurrent recipients (P = 0.002).

CONCLUSION

HCV recurrence post liver transplantation occur more frequently in patients with -174 G/G IL-6 genotype and elevated plasma IL-6 levels.

Development of a gene signature for predicting cirrhosis risk score of chronic liver disease associated with HCV infection in Egyptians

BACKGROUND

Complex diseases such as fibrosis are likely polygenic. Lately, cirrhosis risk score (CRS) clearly discriminated Chronic HCV patients with high-risk versus those with low-risk for cirrhosis better than clinical factors.

METHODS

Herein, the CRS was assessed via genotyping by allelic discrimination assays in 243 HCV Egyptian patients categorized into 164 patients didn't develop HCC (93 mild, 71 advanced fibrosis); and 79 patients developed HCC. APRI and FIB-4 scores were calculated, compared with CRS and correlated with degree of fibrosis progression.

RESULTS

Median of the three CRS, APRI and FIB-4 scores were significantly elevated in late fibrotic and HCC patients (p < 0.001); however CRS displayed proper discrimination (mild fibrosis (0.59; 0.4-0.75), advanced fibrosis (0.75; 0.7-0.86) and HCC (0.73; 0.57-0.77); (p < 0.001)). The ROC analysis of CRS score displayed modest accuracy to discriminate between mild and advanced fibrotic patient; AUC was 0.73; p < 0.0001), while AUC was only 0.57 (p = 0.05) for the discrimination between HCC and no HCC. Moreover, the combination of CRS, APRI and FIB4 lessened the power of correlation (AUC, 0.63 (p < 0.0001)) in fibrosis prognosis. In HCC prognosis, the combination of CRS, APRI and FIB4 in HCC patients showed modest accuracy with AUC, 0.59 (p = 0.0001).

CONCLUSION

The diagnostic accuracy of FIB-4 for predicting liver fibrosis was nearly identical to that of CRS, however the strength of CRS score stemmed from that it is built on 7 SNPs host genetic factor. Our study validates non invasive algorithms for fibrosis prognosis purposes which may aid in decision making for therapeutic intervention.

Evaluation of seven gene signature for predicting HCV recurrence post-liver transplantation

BACKGROUND

Orthotropic liver transplantation (OLT) offers a therapeutic choice for hepatocellular carcinoma (HCC) patients. The poor outcome of liver transplantation is HCV recurrence. Several genome-wide associated studies (GWAS) have reported many genetic variants to be associated with HCV recurrence. Seven gene polymorphisms formed a cirrhosis risk score (CRS) signature that could be used to distinguish chronic HCV patients at high risk from those at low risk for cirrhosis in non-transplant patients. This study aims to examine the association of CRS score and other clinical parameters with the probability for HCC emergence and/or the rate of HCV recurrence following liver transplantation.

RESULTS

Seven gene polymorphisms, forming the CRS, were genotyped by real-time PCR using allelic discrimination protocol in 199 end-stage liver disease patients (79 child A, 43 child B, and 77child C), comprising 106 patients who encountered liver transplantation. Recipient CRS scores were correlated with HCV recurrence (HCV-Rec) at the end of the third year after OLT. Around 81% (39) recipients with low steatosis (LS; < 3.5%) donor percentage revealed no HCV recurrence (non-Rec) (p<0.001). CRS score could distinguish between child A, child B, and child C only at the low-risk group. Among the HCV Rec group 27% (8/30), 40% (12/30), and 33% (10/30) fell into the high, moderate, and low CRS risk groups, respectively. Stepwise logistic regression evinced two features more likely to be seen in HCV-Rec patients: abnormal ALT [OR, 1.1; 95% CI, 1.02-1.2] and donor steatosis >3.5% [OR, 46.07; 95% CI, 1.5-1407.8].

CONCLUSIONS

Accordingly, the CRS score seems to be less useful to predict HCV recurrence after OLT. ALT and donor steatosis (exceed 3.5%) can significantly promote the HCV recurrence post-OLT. Moreover, the combination of MMF and CNI positively heightens HCV recurrence.

Seven gene signature explores the impact of DAAs on the appearance of hepatocellular carcinoma in HCV infected patients

HCV damages the hepatocytes ending with hepatocellular carcinoma (HCC). The direct-acting antivirals (DAAs) treatment has raised hopes for reducing the incidence of HCC. However, several scientific debate regarding the impact of DAAs on the occurrence of HCC in patients with cirrhosis. We aimed to study the Cirrhosis Risk Score (CRS), several clinical factors and tumor characteristics between patients who developed HCC either with or without DAAs treatment "DAA-exposed HCC patients" and "DAA-unexposed HCC patients".

METHODS

CRS was assessed via genotyping by allelic discrimination assays in HCV patients who developed de novo HCC (with DAAs (DAA-exposed HCC patients, n = 50), and without DAAs treatment (DAA-unexposed HCC patients, n = 40)). APRI, FIB-4 scores, and tumor characteristics were assessed.

RESULTS

Around 60% and 48% of DAA-exposed HCC patients and DAA-unexposed HCC patients; respectively had high CRS scores without significant difference. DAA-exposed HCC patients showed elevated Albumin, Hemoglobin and decreased ALT, AST compared with DAA-unexposed HCC patients (P = 0.002, 0.04, <0.001 and 0.006; respectively). FIB4 and APRI didn't reach the statistical difference between the studied groups. DAA-exposed HCC patients have higher overall survival (OS) than DAA-unexposed HCC patients (median: 30 & 15 months; respectively (p = 0.019)). Moreover, no significant differences were observed between the two groups in their focal lesion characteristics.

CONCLUSION

All studied patients are genetically predisposed to develop HCC. Moreover, DAAs significantly improved the OS and the biochemical parameters. No differences between the two groups were detected regarding their tumor characteristics. Accordingly, the appearance of HCC after treatment is attributed to the natural course of cirrhosis.