A. Madejón

Rate and Timing of Hepatitis C Virus Relapse after a Successful Course of Pegylated Interferon plus Ribavirin

Information on the rate and timing of hepatitis C virus (HCV) relapse after treatment with pegylated interferon plus ribavirin is scarce. Among 604 patients treated for chronic hepatitis C, the 386 who were human immunodeficiency virus (HIV) positive attained an end-of-treatment response less frequently and experienced relapse more often than did the 218 who were HIV negative. However, episodes of HCV relapse occurred before week 12 in most cases, regardless of HIV status.

Effects of delayed freezing of liver biopsies on the detection of hepatitis C virus RNA strands

BACKGROUND/AIMS There are no data about the influence of handling conditions of liver biopsies on the integrity of viral RNAs. We studied the influence of the time delay between obtaining and freezing the liver biopsy on the stability of intrahepatic positive and negative hepatitis C virus RNA (HCV-RNA) strands. METHODS Liver samples from 30 anti-HCV patients were included. For each case, one portion of the liver biopsy (first sample) was immediately frozen (20-28 s), while the other section (second sample) was kept at room temperature (1-30 min) before freezing. Each experimental time point was performed in triplicate using liver samples from three different patients. Semi-quantitative analysis of the positive and negative HCV-RNA strands and of the al-antitrypsin mRNA was performed by a Tth-based reverse-transcription polymerase chain reaction. RESULTS A significant time-related decrease in both positive (r=-0.8412, p=0.001) and negative (r=-0.8539, p=0.001) HCV-RNA strand titres was found in the second liver fractions. There were no appreciable changes in RNA titres in those samples frozen after less than 3 min. The RNA titres decreased in all but two samples incubated for 4-30 min. Thus, 3/15 (20%) and 7/11 (64%) of these samples lost positive and negative HCV-RNA strands, respectively. Alpha-1-antitrypsin mRNA titres decreased significantly (r=-0.8935, p=0.01) in those samples kept at room temperature for more than 4 min. CONCLUSION Freezing of liver samples immediately after extraction is crucial to avoid false negative HCV-RNA detection results, especially for the antigenomic RNA strand.

Plasma Ribavirin Trough Concentrations at Week 4 Predict Hepatitis C Virus (HCV) Relapse in HIV-HCV-Coinfected Patients Treated for Chronic Hepatitis C

ABSTRACT The influence of ribavirin trough concentrations (RBV Ctrough) on the risk of hepatitis C virus (HCV) relapse was retrospectively analyzed in 99 HIV-HCV-coinfected patients who achieved end-of-treatment response with pegylated alpha interferon plus weight-based RBV. The independent predictors (odds ratio [OR] [95% confidence interval (CI)]) of HCV relapse were RBV plasma Ctrough of <2.5 μg/ml (4.5 [1.3 to 15.5]), baseline serum HCV RNA (2.5 [1.2 to 5.1]), and HCV genotype 1 or 4 (13.3 [2.6 to 66.7]). Monitoring of RBV Ctrough may permit early adjustment of RBV dosage to avoid HCV relapse.

Development and clinical validation of the Genedrive point-of-care test for qualitative detection of hepatitis C virus

Objective Recently approved direct acting antivirals provide transformative therapies for chronic hepatitis C virus (HCV) infection. The major clinical challenge remains to identify the undiagnosed patients worldwide, many of whom live in low-income and middle-income countries, where access to nucleic acid testing remains limited. The aim of this study was to develop and validate a point-of-care (PoC) assay for the qualitative detection of HCV RNA. Design We developed a PoC assay for the qualitative detection of HCV RNA on the PCR Genedrive instrument. We validated the Genedrive HCV assay through a case–control study comparing results with those obtained with the Abbott RealTime HCV test. Results The PoC assay identified all major HCV genotypes, with a limit of detection of 2362 IU/mL (95% CI 1966 to 2788). Using 422 patients chronically infected with HCV and 503 controls negative for anti-HCV and HCV RNA, the Genedrive HCV assay showed 98.6% sensitivity (95% CI 96.9% to 99.5%) and 100% specificity (95% CI 99.3% to 100%) to detect HCV. In addition, melting peak ratiometric analysis demonstrated proof-of-principle for semiquantification of HCV. The test was further validated in a real clinical setting in a resource-limited country. Conclusion We report a rapid, simple, portable and accurate PoC molecular test for HCV, with sensitivity and specificity that fulfils the recent FIND/WHO Target Product Profile for HCV decentralised testing in low-income and middle-income countries. This Genedrive HCV assay may positively impact the continuum of HCV care from screening to cure by supporting real-time treatment decisions. Trial registration number NCT02992184.

Hepatitis B and D viruses replication interference: Influence of hepatitis B genotype

AIM To study the hepatitis B virus (HBV) and hepatitis D virus (HDV) replication interferences in patients with chronic hepatitis delta infected with different HBV genotypes. METHODS We conducted a transversal study including 68 chronic hepatitis delta (CHD) (37 HIV-positive) patients and a control group of 49 chronic hepatitis B (CHB) (22 HIV-positive) patients. In addition, a dynamic follow-up was performed in 16 CHD patients. In all the samples, the surface antigen of hepatitis B (HBsAg) serum titers were analyzed with the Monolisa HBsAg Ultra system (Bio-Rad), using as quantification standard a serial dilution curve of an international HBsAg standard. Serum HBV-DNA titers were analyzed using the Roche Cobas TaqMan (Roche, Barcelona, Spain), and the serum HDV-RNA using an in-house real-time qRT-PCR method, with TaqMan probes. HBV genotype was determined with the line immunoassay LiPA HBV genotyping system (Innogenetics, Ghent, Belgium). In those patients negative for LiPA assay, a nested PCR method of complete HBsAg coding region, followed by sequence analysis was applied. RESULTS No differences in the HBV-DNA levels were found in CHB patients infected with different HBV genotypes. However, in CHD patients the HBV-DNA levels were lower in those infected with HBV-A than in those with HBV-D, both in HIV negative [median (IQR): 1.25 (1.00-1.35) vs 2.95 (2.07-3.93) log10 (copies/mL), P = 0.013] and HIV positive patients [2.63 (1.24-2.69) vs 7.25 (4.61-7.55) log10 (copies/mL), P < 0.001]. This was confirmed in the dynamic study of the HBV/HDV patients. These differences induce an under-estimation of HBV-A incidence in patients with CHD analyzed with LiPA assay. Finally, the HBsAg titers reflected no significant differences in CHD patients infected with HBV-A or D. CONCLUSION Viral replication interference between HBV and HDV is HBV-genotype dependent, and more evident in patients infected with HBV-genotype A, than with HBV-D or E.

Significance of low HDV replication levels during the natural history of HDV infection: Long-term follow-up

The use of genetic amplification of the hepatitis delta virus (HDV) genome reveals the existence of different HDV replicative behaviours during the natural history of chronic HDV infection. While some of the patients (8/19, 42%) presented high and long-term maintained levels of HDV replication, as detected by slot-blot hybridization, others showed fluctuations from positive to negative, and in 5/7 (71%) polymerase chain reaction (PCR) demonstrated the presence of the HDV genome. Finally, 4 patients were persistently slot-blot-negative and in 3 of them HDV-RNA was detected by PCR in all samples tested. The correlation observed between the low levels of HDV replication and the ALT values, as well as the reactivation observed in one of the patients, suggests that PCR is useful in the virological surveillance of HDV infection, and indicates its usefulness in evaluating the effectiveness of antiviral therapy for chronic hepatitis D.

According to Hepatitis C Virus (HCV) Infection Stage, Interleukin-7 Plus 4-1BB Triggering Alone or Combined with PD-1 Blockade Increases TRAF1low HCV-Specific CD8+ Cell Reactivity

ABSTRACT Hepatitis C virus (HCV)-specific CD8+ T cells suffer a progressive exhaustion during persistent infection (PI) with HCV. This process could involve the positive immune checkpoint 4-1BB/4-1BBL through the loss of its signal transducer, TRAF1. To address this issue, peripheral HCV-specific CD8+ T cells (pentamer-positive [pentamer+]/CD8+ T cells) from patients with PI and resolved infection (RI) after treatment were studied. The duration of HCV infection and the liver fibrosis progression rate inversely correlated with the likelihood of detection of peripheral pentamer+/CD8+ cells. In PI, pentamer+/CD8+ cells had impaired antigen-specific reactivity that worsened when these cells were not detectable ex vivo. Short/midduration PI was characterized by detectable peripheral PD-1+ CD127low TRAF1low cells. After triggering of T cell receptors (TCR), the TRAF1 level positively correlated with the levels of CD127, Mcl-1, and CD107a expression and proliferation intensity but negatively with PD-1 expression, linking TRAF1low to exhaustion. In vitro treatment with interleukin-7 (IL-7) upregulated TRAF1 expression, while treatment with transforming growth factor-β1 (TGF-β1) did the opposite, suggesting that the IL-7/TGF-β1 balance, besides TCR stimulation, could be involved in TRAF1 regulation. In fact, the serum TGF-β1 concentration was higher in patients with PI than in patients with RI, and it negatively correlated with TRAF1 expression. In line with IL-7 increasing the level of TRAF1 expression, IL-7 plus 4-1BBL treatment in vitro enhanced T cell reactivity in patients with short/midduration infection. However, in patients with long-lasting PI, anti-PD-L1, in addition to the combination of IL-7 and 4-1BBL, was necessary to reestablish T cell proliferation in individuals with slowly progressing liver fibrosis (slow fibrosers) but had no effect in rapid fibrosers. In conclusion, a peripheral hyporeactive TRAF1low HCV-specific CD8+ T cell response, restorable by IL-7 plus 4-1BBL treatment, characterizes short/midduration PI. In long-lasting disease, HCV-specific CD8+ T cells are rarely detectable ex vivo, but treatment with IL-7, 4-1BBL, and anti-PD-L1 recovers their reactivity in vitro in slow fibrosers. IMPORTANCE Hepatitis C virus (HCV) infects 71 million people worldwide. Two-thirds develop a chronic disease that can lead to cirrhosis and hepatocellular carcinoma. Direct-acting antivirals clear the infection, but there are still patients who relapse. In these cases, additional immunotherapy could play a vital role. A successful anti-HCV immune response depends on virus-specific CD8+ T cells. During chronic infection, these cells are functionally impaired, which could be due to the failure of costimulation. This study describes exhausted specific T cells, characterized by low levels of expression of the signal transducer TRAF1 of the positive costimulatory pathway 4-1BB/4-1BBL. IL-7 upregulated TRAF1 expression and improved T cell reactivity in patients with short/midduration disease, while in patients with long-lasting infection, it was also necessary to block the negative PD-1/PD-L1 checkpoint. When the results are taken together, this work supports novel ways of restoring the specific CD8+ T cell response, shedding light on the importance of TRAF1 signaling. This could be a promising target for future immunotherapy.

Hepatitis C virus-mediated Aurora B kinase inhibition modulates inflammatory pathway and viral infectivity

BACKGROUND & AIMS Chronic hepatitis C is a leading cause of chronic liver disease, cirrhosis and hepatocellular carcinoma. DNA methylation and histone covalent modifications constitute crucial mechanisms of genomic instability in human disease, including liver fibrosis and hepatocellular carcinoma. The present work studies the consequences of HCV-induced histone modifications in early stages of infection. METHODS Human primary hepatocytes and HuH7.5 cells were transiently transfected with the core protein of hepatitis C virus (HCV) genotypes 1a, 1b, and 2a. Infectious genotype 2a HCV in culture was also used. RESULTS We show that HCV and core protein inhibit the phosphorylation of Serine 10 in histone 3. The inhibition is due to the direct interaction between HCV core and Aurora B kinase (AURKB) that results in a decrease of AURKB activity. HCV and core significantly downregulate NF-κB and COX-2 transcription, two proteins with anti-apoptotic and proliferative effects implicated in the control of the inflammatory response. AURKB depletion reduced HCV and core repression of NF-κB and COX-2 gene transcription and AURKB overexpression reversed the viral effect. AURKB abrogation increased HCV specific infectivity which was decreased when AURKB was overexpressed. CONCLUSIONS The core-mediated decrease of AURKB activity may play a role in the inflammatory pathway during the initial steps of viral infection, while ensuring HCV infectivity.

In vitro inhibition of the hepatitis delta virus replication mediated by interferon and trans-ribozyme or antisense probes.

BACKGROUND/AIMS In this study, the inhibition of hepatitis delta virus replication mediated by trans-ribozyme and antisense probes, alone or in combination with recombinant interferon alpha-2a, has been assayed. METHODS A 60-nucleotide-long designed trans-ribozyme, which contains the catalytic core of the hammerhead ribozyme, and a 163-nucleotide-long antisense probe were directed against the same region of the viral genome in in vitro and cell culture systems. RESULTS The ribozyme activity, assayed in a chemically isolated system, resulted in the trans-cleavage of 10-20% of the 40-nucleotide-long RNA substrate. A 5-nucleotide deletion in one of the flanking arms, obtained by random mutagenesis, resulted in enhancement of the trans-cleavage activity in as many as 40-60% of the substrate molecules. The efficiency of the optimized trans-ribozyme and antisense probes against the complete viral genome was assayed in a cell culture system. The inhibitory efficacy (25%) of the trans-ribozyme is lower than that of the antisense probe (35%) or interferon at 1000 U/ml (47%). An enhancement of the interferon efficacy was achieved when it was administered in cells having a previous basal expression of ribozyme (70%) or antisense probes (83%). CONCLUSIONS These results suggest that the combination of ribozyme or antisense probes with interferon could be a promising approach to the treatment of RNA virus infections.