Gut immune response in the presence of hepatitis C virus infection

Gut virome: New key players in the pathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic inflammatory illness of the intestine. While the mechanism underlying the pathogenesis of IBD is not fully understood, it is believed that a complex combination of host immunological response, environmental exposure, particularly the gut microbiota, and genetic susceptibility represents the major determinants. The gut virome is a group of viruses found in great frequency in the gastrointestinal tract of humans. The gut virome varies greatly among individuals and is influenced by factors including lifestyle, diet, health and disease conditions, geography, and urbanization. The majority of research has focused on the significance of gut bacteria in the progression of IBD, although viral populations represent an important component of the microbiome. We conducted this review to highlight the viral communities in the gut and their expected roles in the etiopathogenesis of IBD regarding published research to date.

Microbiota and hepatitis C virus in the era of direct-acting antiviral agents

The gut microbiota plays a fundamental role in Hepatitis C Virus (HCV)-related liver disease. Indeed, HCV infection alters the gut microbiota, whereas intestinal dysbiosis induces an underlying inflammatory state. This status may lead to liver disease progression. The advent of direct acting antivirals (DAAs) was a turning point in the history of HCV infection, which enhances the chances of recovery. Beyond the elimination of the virus, DAA therapy can affect the gut microbiota of the HCV patient. The study of the gut microbiota in the patient with HCV-related liver disease could be the first step in understanding the etiopathogenesis of hepatopathy thereby opening the way to new therapeutic opportunities. Herein we evaluate current knowledge regarding the gut microbiota in patients with HCV infection and the impact of DAA therapy.

Molecular Communications in Viral Infections Research: Modeling, Experimental Data, and Future Directions

Hundreds of millions of people worldwide are affected by viral infections each year, and yet, several of them neither have vaccines nor effective treatment during and post-infection. This challenge has been highlighted by the COVID-19 pandemic, showing how viruses can quickly spread and impact society as a whole. Novel interdisciplinary techniques must emerge to provide forward-looking strategies to combat viral infections, as well as possible future pandemics. In the past decade, an interdisciplinary area involving bioengineering, nanotechnology and information and communication technology (ICT) has been developed, known as Molecular Communications. This new emerging area uses elements of classical communication systems to molecular signalling and communication found inside and outside biological systems, characterizing the signalling processes between cells and viruses. In this paper, we provide an extensive and detailed discussion on how molecular communications can be integrated into the viral infectious diseases research, and how possible treatment and vaccines can be developed considering molecules as information carriers. We provide a literature review on molecular communications models for viral infection (intra-body and extra-body), a deep analysis on their effects on immune response, how experimental can be used by the molecular communications community, as well as open issues and future directions.

Impact of interleukin IL-6 rs-1474347 and IL-10 rs-1800896 genetic polymorphisms on the susceptibility of HCV-infected Egyptian patients to hepatocellular carcinoma

Hepatitis C virus (HCV) is considered leading cause of cirrhosis and hepatocellular carcinoma (HCC). We aimed to examine the association of IL-6 and IL-10 single-nucleotide polymorphisms with the progression of chronic HCV (CHC) infection to cirrhosis and HCC. For comparative purposes, four groups were enrolled; chronic HCV group (CHC, n = 22), HCV-related liver cirrhosis group (HCV-LC, n = 22), HCV-related HCC group (HCV-HCC, n = 54), and an apparently healthy control group (controls, n = 48). HCC diagnosis and staging were in concordance to Barcelona Clinic Liver Cancer (BCLC) staging system. IL-6 rs-1474347 and IL-10 rs-1800896 genotyping was performed by allelic (VIC- and FAM-labeled) discrimination method using assay-on-demand TaqMan real-time PCR assays. For IL-6 rs1474347, the AA genotype was more frequent in CHC, HCV-LC, and HCV-HCC compared to controls. Also, the IL-6 rs1474347 AC genotype was favorable for the progression of HCV chronic infection to cirrhosis and HCC. On the other hand, the IL-10 rs1800896 TT genotype was found to be prominent in the HCC group. Additionally, the IL-10 rs180096 TT genotype was favorable for the progression of chronic HCV infection to cirrhosis and HCC. Furthermore, higher levels of AFP were observed in HCC patients with IL-6 rs1474347 AA genotype and HCC patients with IL-10 rs1800896 CC and TT genotypes. Screening for IL-6 rs 1474347 AC genotype and IL-10 rs180096 TT genotype as well as the determination of AFP level showed to be good markers for examining the susceptibility of HCV Egyptian patients to develop cirrhosis and HCC.

Correlation Between Vascular Endothelial Growth Factor and Long-Term Occurrence of HCV-Related Hepatocellular Carcinoma After Treatment with Direct-Acting Antivirals

We aimed to evaluate the correlation between vascular endothelial growth factor (VEGF) and long-term occurrence of hepatocellular carcinoma after HCV treatment with direct-acting antivirals (DAAs) and the HCC stage. Two groups with HCV-related liver cirrhosis and HCC were included: group 1, HCC following DAAs; group 2, HCC did not receive DAAs. The serum level of VEGF and HCC staging was evaluated. The duration between DAAs and HCC was 21.81 ± 11.66 months. Portal vein thrombosis (PVT) was observed more in group 1 (31%). VEGF was relatively elevated in group 1 compared to group 2. HCC patients after DAAs, showed elevated VEGF with frequent PVT.

Distribution of naturally -occurring NS5B resistance-associated substitutions in Egyptian patients with chronic Hepatitis C

Background

NS5B polymerase inhibitors represent the cornerstone of the present treatment of Hepatitis C virus infection (HCV). Naturally occurring substitution mutations to NS5B inhibitors have been recorded. The current study intended to demonstrate possible natural direct acting antiviral (DAA)—mutations of the HCV NS5B region in HCV patients in Minia governorate, Egypt.

Methods

Samples were collected from 27 treatment-naïve HCV patients and 8 non-responders. Out of 27 treatment-naïve patients, 17 NS5B sequences (amino acids 221–345) from treatment-naïve patients and one sample of non-responders were successfully amplified. Nucleotide sequences have been aligned, translated into amino acids, and compared to drug resistance mutations reported in the literature.

Results

NS5B amino acid sequence analysis ensures several novel NS5B mutations existence (more than 40 substitution mutations) that have not been previously documented to be correlated with a resistant phenotype. It was found that K304R (82.4%), E327D and P300T (76.5% each) substitutions were the most distributed in the tested samples, respectively. S282T, the major resistance mutation that induces high sofosbuvir-resistance level in addition to other reported mutations (L320F/C) and (C316Y/N) were not recognized. Q309R mutation is a ribavirin-associated resistance, which was recognized in one strain (5.9%) of genotype 1g sequences. Besides, one substitution mutation (E237G) was identified in the successfully amplified non-responder sample.

Conclusion

Our study showed various combinations of mutations in the analyzed NS5B genes which could enhance the possibility of therapy failure in patients administered regimens including multiple DAA.

Cytotoxic Chemotherapy as an Alternative for Systemic Treatment of Advanced Hepatocellular Carcinoma in Developing Countries

Systemic therapy options nowadays for advanced hepatocellular carcinoma (HCC) are either immunotherapy with immune checkpoint inhibitors or targeted therapy. As the incidence of liver cancer is much higher in developing countries, these new medications are not readily accessible for most of the patients. Cytotoxic chemotherapy agents are more available and affordable in developing countries. We are trying to explore the effectiveness of the newer cytotoxic agents in the systematic treatment for advanced HCC. This is a systematic review of all randomized controlled trials since 1997 that utilized systemic cytotoxic chemotherapy agents in the systemic treatment for advanced HCC using Scopus, PubMed, and Cochrane library up to February 2020. Six randomized trials were found. Different drugs and dosages were used, so it was statistically inappropriate to conduct a meta-analysis. No Phase III trial showed statistically significant overall survival (OS) benefit for cytotoxic chemotherapy, except subgroup analysis of Chinese patients in one study who had leucovorin, fluorouracil, and oxaliplatin (FOLFOX) regimen. There was no significant progression-free survival (PFS) or response rate in the Phase II trials. There are not enough data to infer the actual benefits of systemic cytotoxic chemotherapy in advanced HCC. However, oxaliplatin-based regimens may give feasible results. Health systems with limited access to targeted therapy and immunotherapy agents may use oxaliplatin-based regimens in clinical trials for advanced HCC. These results should be confirmed in multiple future randomized clinical trials.

T follicular helper and T follicular regulatory cells in colorectal cancer: A complex interplay

Colorectal cancer is considered to be one of the major causes of morbidity and mortality all over the world. T Follicular helper (T_FH) and T follicular regulatory (T_FR) cells are specialized providers of T-cells to help B-cells and shaping germinal centers (GC) response. Recent researches reported a high percentage of T_FH and T_FR in different infectious diseases and certain malignancies. However, their functional role in human colorectal cancer (CRC) is relatively unknown. Furthermore, recent studies show that the interaction of both T_FH cells and T_FR cells are essential to promote several diseases. Under the control of specific cytokines and B-cell lymphoma 6 transcription factor (Bcl-6), the major transcription factor of T_FH cells, T_FH, can expand to the other distinct CD4 + T helper cells (TH1, TH2, and TH17) which exert a different role in the development of CRC. This review aims to discuss these suggested roles of the two-opposite subset of follicular T cells in colorectal cancer immune pathogenesis.

Prognostic impact of toll-like receptors 2 and 4 expression on monocytes in Egyptian patients with hepatocellular carcinoma

Toll-like receptors (TLRs) have a role in chronic inflammation. Still, little is known about the expression of TLRs in hepatocellular carcinoma (HCC). Herein, we tried to assess the prognostic value of TLR2 and TLR4 expression on circulating monocytes in HCC patients and correlate their levels with some clinical, laboratory data, and treatment outcomes. Forty patients with hepatic focal lesions diagnosed radiologically as HCC by triphasic multislice CT pelviabdominal and chest, and in some patients MRI diffusion and 38 age and sex matching healthy controls were enrolled in the study. Subjects were evaluated for liver functions, alpha-fetoprotein (AFP), imaging, response to different treatments, and overall survival. TLR2 and TLR4 expression by monocytes was detected by flow cytometry. The expression of both TLR2 and TLR4 on monocytes was significantly increased in HCC patients than the controls, in patients with more progressive HCC than those with lower progression and in patients with poor response to treatment than patients with better treatment response. Moreover, their levels showed positive correlations with ALT, AST, and AFP and inverse correlations with the overall survival of HCC patients. The results of the current study suggest that increased expression ofTLR2 and TLR4 on peripheral monocytes might reflect the development and progression of HCC and can be used to indicate poor prognosis. In addition, high expression of TLR2 correlated significantly with poor response to treatment, while high expression of both TLR2 and TLR4 were associated with poor survival. Our findings will help to design more studies on the role of TLRs in HCC pathogenesis and prognosis which may provide new therapeutic targets for HCC.

Nanomedicine as a future therapeutic approach for Hepatitis C virus

Hepatitis C virus (HCV) is not easily cleared from the human body and in most cases turned into chronic infection. This chronicity is a major cause of liver damage, cirrhosis and hepatocellular carcinoma. Therefore, immediate detection and treatment of HCV guarantees eradication of the virus and prevention of chronicity complications. Since discovery of HCV in 1989, several emerging treatments were developed such as polyethylene glycol(PEG)-ylated interferon/ribavirin, direct acting antivirals and host targeting antivirals. Despite the progress in anti-HCV therapy, there is still a pressing need of new approaches for affordable and effective drug delivery systems using nanomedicine. In this review, the contribution of nanoparticles as a promising delivery system for HCV immunizing, diagnostic and therapeutic agents are discussed.

Increased frequency and FOXP3 expression of human CD8+CD25High+ T lymphocytes and its relation to CD4 regulatory T cells in patients with hepatocellular carcinoma

The mechanism of action of CD8⁺CD25^High+FOXP3⁺ T cells in hepatocellular carcinoma (HCC) has not been fully understood. Herein, the role of CD8⁺CD25^High+FOXP3⁺ T cells in HCC was compared with that of CD4⁺CD25^High+FOXP3⁺ regulatory T cells (conventional Tregs). Thirty-five patients with HCC and twenty age and sex-matched healthy adults (controls) were enrolled. The percentage of CD8⁺CD25^High+FOXP3⁺ T cells and conventional Tregs in peripheral blood was measured by flow cytometry. Our results revealed that the percentage of peripheral CD8⁺CD25^High+FOXP3⁺ T cells in HCC patients was significantly higher than controls (P = 0.005). The conventional Tregs showed the same trend with a higher level in HCC than controls (P < 0.0001). FOXP3 expression of CD8⁺CD25^High+ T cells is higher than that of CD8⁺CD25^low+ and CD8⁺CD25^Negative T cells. The percentage of CD8⁺CD25^High+FOXP3⁺ T cells positively correlated with that of conventional Tregs in HCC patients but not in controls. The higher alpha-fetoprotein positively correlated with the higher CD8⁺CD25^High+FOXP3⁺ T cells and conventional Tregs (R2 = 0.481, P < 0.0001 and R2 = 0.249, P = 0.001, respectively). The frequency of both CD8⁺CD25^High+FOXP3⁺ T cells and conventional Tregs was significantly increased in HCC with multiple lesions compared with those with one or two lesions. In conclusion: CD8⁺CD25^High+FOXP3⁺ T cells similar to conventional Tregs might be used as biomarkers of HCC progression. Therapy targeting the peripherally expanded CD8⁺CD25^High+FOXP3⁺ T cells may provide a novel perspective for HCC treatment.

Frequency and Implications of myeloid-derived suppressor cells and lymphocyte subsets in Egyptian patients with hepatitis C virus-related hepatocellular carcinoma

BACKGROUND AND AIM

Myeloid-derived suppressor cells (MDSCs) play a pivotal role in tumor immunity and induction of immune tolerance to a variety of antitumor effectors, including T lymphocytes. Herein, we tried to evaluate the frequency and clinical significance of MDSCs and different lymphocyte subsets in hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC).

METHODS

Four groups were enrolled; chronic HCV (CHC; n = 40), HCV-related liver cirrhosis (n = 40), HCV-related HCC (HCV-HCC; n = 75), and healthy control group (n = 20). The percentage of peripheral lymphocytes subsets and total MDSCs with their main two subsets; monocytic (M-MDSCs) and granulocytic (G-MDSCs) was evaluated by flow cytometry.

RESULTS

The frequency of total MSDCs and M-MDSCs was significantly elevated in HCV-HCC especially patients with advanced stage HCC compared with those with early-stage HCC. The frequency of total MSDCs and M-MDSCs was positively correlated with ALT, AFP, and HCV viral load and negatively correlated with CD8⁺ T-cell frequency. CD4 ⁺ T cells were significantly decreased in HCV-HCC patients. The frequency of CD4 ⁺ T cells and CD8 ⁺ T cells was negatively correlated with AFP and AST, but not with albumin or HCV viral load.

CONCLUSION

Taken together, our data suggest that MDSCs, M-MDSCs, and lymphocyte subsets are associated with the development and progression of HCV-related HCC.

Gut microbiome alterations in patients with stage 4 hepatitis C

Background

Hepatitis C virus (HCV) causes debilitating liver diseases, which may progress to cirrhosis and cancer, and claims 500,000 annual lives worldwide. While HCV epidemiology, pathophysiology, and therapy are being deeply studied, rare attention is given to reciprocal interactions between HCV infection , HCV-induced chronic liver diseases, and the human gut microbiome. As Egypt has the world’s highest prevalence of HCV infections, we launched this study to monitor differences in the gut microbial community composition of Egyptian HCV patients that may affect, or result from, the patients’ liver state.

Results

To this end, we analyzed stool samples from six stage 4-HCV patients and eight healthy individuals by high-throughput 16S rRNA gene sequencing using Illumina MiSeq. Overall, the alpha-diversity of the healthy persons’ gut microbiomes was higher than those of the HCV patients. Whereas members of phylum Bacteroidetes were more abundant in HCV patients, healthy individuals had higher abundance of Firmicutes, Proteobacteria, and Actinobacteria. Genus-level analysis showed differential abundance of Prevotella and Faecalibacterium (higher in HCV patients) vs. Ruminococcus and Clostridium (healthy group), indicating that the higher abundance of Bacteroidetes in HCV patients is most likely due to Prevotella overabundance. The probiotic genus, Bifidobacterium, was only observed in the microbiotas of healthy individuals.

Conclusions

To the best of our knowledge, this study provides a first overview of major phyla and genera differentiating stage 4-HCV patients from healthy individuals and suggests possible microbiome remodeling in chronic hepatitis C, possibly shaped by bacterial translocation as well as the liver’s impaired role in digestion and protein synthesis. Future studies will investigate the microbiome composition and functional capabilities in more patients while tracing some potential biomarker taxa (e.g., Prevotella, Faecalibacterium vs. Bifidobacterium).

Electronic supplementary material

The online version of this article (doi:10.1186/s13099-016-0124-2) contains supplementary material, which is available to authorized users.

Extra-hepatic infection of hepatitis C virus in the colon tissue and its relationship with hepatitis C virus pathogenesis

Extra-hepatic compartments might contribute to hepatitis C virus (HCV) persistence and extra-hepatic manifestations. Therefore, we investigated HCV infection in colonic tissue in patients with chronic hepatitis C (CHC) and its relationship with HCV pathogenesis. Colonic biopsies were collected from three groups with CHC infection: treatment naïve (TN; n=12), non-responders (NR; n=10) to anti-HCV therapy (pegylated interferon-α and ribavirin) and sustained virologic response (SVR; n=10) and from a fourth healthy control group (n=10). Liver biopsies were examined to assess inflammation and fibrosis. HCV infection and colonic T regulatory (Treg) frequency were detected by immunohistochemistry. HCV core and NS3 proteins were detected in B cells and macrophage/monocytes of 42 % and 25 % of TN and 50 % and 30 % of NR, respectively, but not in SVR or control group. The numbers of cells expressing HCV proteins were positively correlated with both HCV viral load and colonic Treg frequency. A significant negative correlation between HCV-expressing cells with both liver inflammation and fibrosis was identified. Our study provides evidence that HCV can infect B cells and macrophages of the colon. The correlations between HCV infection in colonic tissue and HCV viral load and liver pathology underline the significance of this extra-hepatic infection in HCV pathogenesis and response to therapy.

Association of colonic regulatory T cells with hepatitis C virus pathogenesis and liver pathology

BACKGROUND AND AIM

Forkhead box protein P3 (FoxP3)(+) regulatory T (Treg ) cells play a fundamental role in maintaining the balance between the tissue-damaging and protective immune response to chronic hepatitis C (CHC) infection. Herein, we investigated the frequency of Treg cells in the colon and their potential relationship to the various CHC outcomes and hepatic histopathology.

METHODS

Colonic biopsies were collected from three groups with CHC: treatment naïve (TN; n = 20), non-responders (NR; n = 20), sustained virologic response (SVR; n = 20), and a fourth healthy control group (n = 10). The plasma viral loads and cytokines levels were determined by quantitative real-time polymerase chain reaction, and ELISA, respectively. Liver biopsies were examined to assess inflammatory score and fibrosis stage. Colonic Treg frequency was estimated by immunohistochemistry using confocal microscopy.

RESULTS

A significant increase in the frequency of colonic Treg was found in TN, and NR groups compared with the control and SVR group. The frequency of colonic Treg , plasma interleukin (IL)-10 and IL-4 levels were significantly positively correlated with viral load and negatively correlated with METAVIR inflammatory score, and fibrosis stages.

CONCLUSION

Colonic Treg cells are negatively correlated with liver inflammation and hepatitis C virus (HCV) viral load, which suggests a strong linkage between gut-derived Treg cell populations and HCV infection.