Hepatitis C virus (HCV) treatment uptake and changes in the prevalence of HCV genotypes in HIV/HCV-coinfected patients.

The efficacy of current hepatitis C therapy in HIV/HCV-coinfected patients is largely dependent on HCV genotype. The annual prevalence of HCV genotypes/subtypes and their influence on HCV clearance with antiviral treatment were examined in a dynamic cohort of HIV/HCV-coinfected patients followed up in Madrid since 2000. Patients entered the cohort at first visit and left the cohort when HCV clearance was achieved with HCV therapy or when follow-up was interrupted for any reason, including death. A total of 672 HIV/HCV-coinfected patients constituted the cohort. The mean follow-up time was 5.5 years, corresponding to 4108 patient-years. Mean age at entry was 37 years, and 73% were men and 86% were intravenous drug users. Overall distribution of HCV genotypes was as follows: 57.1% HCV-1 (1a: 29.2%, 1b: 20.4%, unknown: 7.6%), 1.3% HCV-2, 25.4% HCV-3 and 15.9% HCV-4. A total of 274 (40.8%) patients were treated with peginterferon-ribavirin, of whom 116 (42.3%) achieved HCV clearance following 1-3 courses of therapy. The proportion of HCV-1/4 rose from 71.7% in 2000 to 76.8% in 2008, whereas the proportion of HCV-2/3 fell from 28.1% in 2000 to 23.2% in 2008. The yearly prevalence increased for HCV-1 (R(2) : 0.92, b: 0.59, P < 0.001) and HCV-4 (R(2) : 0.77, b: 0.33, P < 0.005) and conversely diminished for HCV-3 (R(2) : 0.94, b: -0.82, P < 0.001). In summary, the prevalence of HCV-1 and HCV-4 has increased over the last decade in HIV/HCV-coinfected patients, whereas conversely it has declined for HCV-3, in association with the wider use of HCV therapy (41%) in this population.

Lack of hepatitis E virus infection in HIV patients with advanced immunodeficiency or idiopathic liver enzyme elevations.

Hepatitis E virus (HEV) is an enterically transmissible RNA agent that causes self-limited acute hepatitis. Recent reports have highlighted that organ-transplant recipients may develop chronic hepatitis E and progress to cirrhosis. Similar cases could occur in HIV patients. We have investigated 50 HIV-infected individuals with CD4 counts <200 cells/mm(3) and 43 with cryptogenic hepatitis. None of them showed HEV viremia. Thus, HEV infection does not seem to be prevalent in the HIV population and accordingly universal HEV vaccination is not warranted in these patients.

Adsorption of polyethyleneimine on silver nanoparticles and its interaction with a plasmid DNA: a surface-enhanced Raman scattering study.

Raman spectroscopy is applied in this work to study the adsorption of poly(ethyleneimine) (PEI) on Ag nanoparticles obtained by reduction with citrate, as well as to the study of the interaction between PEI and a plasmid. The surface-enhanced Raman spectroscopy (SERS) affords important information about the interaction and orientation of the polymer on the particles. In particular we have found that this polymer interacts with the surface through their amino groups in an interaction which also involves a change in the protonation state of amino groups as well as an increase of the chain order. This interaction implies a charge-transfer effect as deduced from the strong resonant effect in Raman spectra obtained at different excitation wavelengths. The complex formed by PEI and a plasmid, obtained by encoding the HBV (hepatitis B virus) genome inside the EcoRI restriction site of pGEM vector, was also studied by SERS. The interaction between both polymers leads to a conformational change affecting both macromolecules that can be detected by Raman at different excitation wavelengths. PEI undergoes a change to a more disordered structure as well as an increase of the number of protonated amino groups. The plasmid undergoes a structural change from A-DNA structure to B-DNA, along with a change in the superhelicity resulting in a more lineal structure when the plasmid interacts with PEI.

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.

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.

GB virus C RNA in serum, liver, and peripheral blood mononuclear cells from patients with chronic hepatitis B, C, and D.

BACKGROUND & AIMS: No conclusive data about GB virus C (GBV-C) tropism are available. We have studied the presence of genomic and antigenomic GBV-C RNA in serum, liver, and peripheral blood cells of 56 patients with chronic hepatitis B, C, or D virus infection. METHODS: Genomic and antigenomic GBV-C RNA were detected by reverse-transcription nested polymerase chain reaction. Specificity was confirmed by sequencing, by chemical modification of the RNA, and by using tagged primers. RESULTS: Genomic GBV-C RNA was found in 10 of 56 (18%) of the sera. In contrast, antigenomic strand was not detected. The sequence of the amplified GBV-C RNA from 3 patients showed a 96% homology among them and from 83% to 88% with previously described isolates. Genomic GBV-C RNA was found in 7 of 7 liver samples of the patients with serum GBV-C RNA. In 6 of these 7 patients (85%), antigenomic strand was found. Genomic RNA was found in 7 of 7 of the peripheral blood cell samples of the same 7 patients. Antigenomic GBV-C RNA was not found in these cells. CONCLUSIONS: These results suggest that GBV-C is a hepatotropic virus that replicates in the human liver. The data do not support a role for GBV-C in chronic liver disease.

Detection of hepatitis G virus from serum and liver of a patient with long-term liver dysfunction after autologous bone marrow transplantation.

Long-term effects after blood or bone marrow transplantation (BMT) are emerging as an important issue, as more patients are included in BMT programmes and as this procedure becomes more successful. Long-term liver dysfunction, mainly due to chronic graft-versus-host disease or hepatitis C virus infection, is a well-known complication. Nevertheless, the diagnosis of liver disease in this patient group is sometimes difficult and, despite adequate studies, it may remain undetected. A novel hepatitis-associated virus, hepatitis G virus (HGV), has recently been identified. The virus belongs to the Flaviviridae family and is known to be parenterally transmitted, although there is no clear evidence to implicate this agent in causing acute or chronic hepatitis. We report a patient who developed mild, but persistent, abnormalities in transaminases for 2 years after an autologous BMT. HGV RNA was detected in both serum and liver. HGV RNA persisted in serum for at least 8 months. No other known hepatitis virus was found. This report provides the first direct evidence of a patient with long-term liver abnormalities after a BMT in whom the only known hepatitis virus isolated was the HGV.

Hepatitis B and D genomes in hepatitis B surface antigen negative patients with chronic hepatitis C.

Hepatitis B and hepatitis D viral genomes were tested by nested polymerase chain reaction in the serum and liver of 69 hepatitis B surface antigen (HBsAg) negative, anti-hepatitis C virus (HCV) positive patients (47 with HCV RNA and 22 without HCV RNA). Serum hepatitis B virus (HBV) DNA-was detected in 49% of the patients with HCV-RNA and in 64% of those without HCV-RNA. Furthermore, intrahepatic HBV-DNA was found in four of five (80%) of the biopsies analysed. Delta genome was found in 72% and 73%, respectively, of the anti-HCV positive patients with or without HCV-RNA. In addition, intrahepatic delta virus genome was detected in another four liver biopsies studied. In the group of patients with HCV-RNA, the simultaneous presence of hepatitis B and D genomes was statistically higher in transfused patients than in drug addicts, or in those with an unknown infection route (P < 0.001). These results show a high percentage of B and D genomes in HBsAg negative patients with anti-HCV, irrespective of the presence or absence of the HCV genome. However, the clinical implications of this finding should be examined in future studies.

Ribozymes: structure, characteristics and use as potential antiviral agents.

Ribozymes are RNA molecules that can cut or ligate other RNA molecules catalytically. Several different ribozymes have been studied. In this paper, the hammerhead and the hepatitis delta virus (HDV) ribozymes are described, as well as their possible use as antiviral therapy.

Hepatitis delta virus infection: molecular biology and treatment.

Hepatitis delta virus is a defective human infectious agent which causes severe hepatic damage in hepatitis B virus-infected patients. Although prophylactic steps and the development, in certain countries, of efficient vaccination programs against hepatitis B virus have led to a diminution of the incidence rate of this disease, hepatitis D is still an important health problem. Hepatitis D infection is therefore associated with a worse clinical evolution than hepatitis B infection alone. On the other hand, the different therapeutic strategies being assayed at present including the use of interferon, have shown to be inefficient in the treatment of this disease. In this article, different aspects of the molecular biology and natural history of the infection, specially focused on those unknown aspects of this virus, are discussed. Finally, we have included a revision of the current state of hepatitis D treatment, as well as a comment of the new experimental strategies, like the use of antisense probes and trans-ribozyme activities.

Treatment of chronic hepatitis D virus infection with low and high doses of interferon-alpha 2a: utility of polymerase chain reaction in monitoring antiviral response.

We examined the efficacy of decreasing high doses (beginning at 18 MU/day) of interferon-alpha 2a vs. that of daily low doses (3 MU) in the treatment of chronic hepatitis delta virus infection. Patients treated with 18 MU had a somewhat higher frequency of normalization of serum ALT levels than patients treated with low doses (31% and 12%, respectively, on an intention-to-treat basis). A decrease in the percentage of hepatitis D virus RNA positivity was observed in both groups at the end of treatment. Thus, whereas in baseline samples 10 (62%) of the patients in each group were positive for hepatitis D virus RNA in serum on slot-blot hybridization, these numbers decreased to 5 (31%) and 4 (25%) patients in groups 1 and 2, respectively, at the end of therapy. However, hepatitis D virus RNA, detected by means of nested polymerase chain reaction, remained in all but two (one in each group) patients who completed the treatment. Finally, during posttreatment follow-up, hepatitis D virus RNA levels returned to baseline values, and only one patient remained negative for this marker. The beneficial effect of interferon-alpha was only transient. Only two patients (one from each treatment group) had persistently normal serum ALT levels after 18 mo of follow-up. Finally, the presence of serum hepatitis D virus RNA at the end of therapy, detected with nested polymerase chain reaction, might be a good marker for the prediction of viral replication relapse.

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.

Hepatitis delta virus RNA detection in chronic HBsAg carriers with and without HIV infection.

Hepatitis delta virus (HDV) RNA detection was carried out, using a full-length HDV RNA probe, in serum of 43 patients with chronic HDV infection. Among them, 30 cases (70%) were HDV RNA-positive. With respect to other HDV markers, serum HDAg (detected by immunoblot) was found in 33 patients (77%) and IgM anti-HD in 29 (67%). A similar percentage of HDV RNA-positive patients with and without circulating hepatitis B virus (HBV) DNA (32.5 vs. 37%, respectively) was found. Antibodies against the human immunodeficiency virus (HIV) were detected in 15/43 subjects studied. The presence of HDV RNA was significantly higher (p less than 0.05) in anti-HIV-seropositive cases (93%) than in the HIV-seronegative ones (57%). Moreover, simultaneous HDV and HBV replication was found more frequently (60 vs. 18%, p less than 0.05) and at higher levels among the anti-HIV-positive patients than in the rest. In addition, in most of the anti-HIV-positive subjects, HDV RNA and HBV DNA were constantly positive during a whole year of follow-up.

Detection of HDV-RNA by PCR in serum of patients with chronic HDV infection.

In this paper, we studied the usefulness of polymerase chain reaction (PCR) in HDV-RNA detection. Using serial dilutions of serum samples of known concentrations of HDV-RNA, PCR was 10,000-times more sensitive than slot-blot hybridization. PCR was used for the detection of HDV-RNA in 33 serum samples negative to HDV-RNA by conventional slot-blot hybridization. HDV-RNA was detected in 18/33 (54%) of the samples included in this study using PCR. When positivity to a viral genome was related to other viral replication markers, it was found that among the 18 patients positive to the viral genome, 13 (72%) had hepatitis delta antigen in the liver, and five (28%) were negative. In conclusion, HDV-RNA detection by gene amplification is 10,000-times more sensitive than slot-blot hybridization, and allows the detection of viral replication in patients without other viral replication markers.