Hepatitis C virus (HCV) causes persistent infection in the majority of infected individuals. The mechanisms of persistence and clearance are only partially understood. Antibodies (Abs) against host cell entry receptors have been shown to inhibit HCV infection in cell culture and animal models. In this study, we aimed to investigate whether anti‐receptor Abs are induced during infection in humans in vivo and whether their presence is associated with outcome of infection. We established an enzyme‐linked immunosorbant assay using a recombinant CD81‐claudin‐1 (CLDN1) fusion protein to detect and quantify Abs directed against extracellular epitopes of the HCV CD81‐CLDN1 coreceptor complex. The presence of anti‐receptor Abs was studied in serum of patients from a well‐defined cohort of a single‐source HCV outbreak of pregnant women and several control groups, including uninfected pregnant women, patients with chronic hepatitis B and D virus (HBV/HDV) infection, and healthy individuals. Virus‐neutralizing activity of Abs was determined using recombinant cell culture–derived HCV (HCVcc). Our results demonstrate that HCV‐infected patients have statistically significantly higher anti‐CD81/CLDN1 Ab titers during the early phase of infection than controls. The titers were significantly higher in resolvers compared to persisters. Functional studies using immunoadsorption and HCV cell culture models demonstrate that HCV‐neutralizing anti‐receptor Abs are induced in the early phase of HCV infection, but not in control groups. Conclusion: The virus‐neutralizing properties of these Abs suggest a role for control of viral infection in conjunction with antiviral responses. Characterization of these anti‐receptor Abs opens new avenues to prevent and treat HCV infection. (Hepatology 2015;62:726–736)
Objective: The aim of our study was to investigate whether an antiretroviral regimen including ABC and AZT can be used to improve or maintain neuropsychological and neurophysiological parameters and effectively suppress HIV Viral Load (VL) in the Cerebrospinal Fluid (CSF). Design: An open prospective observational study Methods: 11 HIV-infected patients of all disease stages were assessed at four visits: before combined antiretroviral treatment (cART) was started or changed as well as 6, 12 and 24 months later. At each visit subjects underwent comprehensive neuropsychological (NP) testing as well as neurological and neurophysiological exam. HIV VL was measured in paired plasma and CSF samples. NP results were compared to a historical untreated matched control group and correlated to HIV duration, viral load as well as CD4 nadir. Results: 3 patients fulfilled the criteria of Asymptomatic Neurocognitive Impairment (ANI) at baseline. A group comparison to the untreated control group at baseline revealed significantly worse results in the study population in 4 cognitive domains: executive and visuoperceptual functions, figural memory and verbal fluency. Executive function correlated significantly with the CSF viral load. At the end of the observational time all treated study patients showed normal NP performance while the untreated controls deteriorated in motor functions. Conclusions: HIV-individuals, who were treated with the CNS penetrating drugs ABC and AZT, have shown neurocognitive improvement compared to an untreated control group suggesting that this treatment may prevent neurocognitive impairment in HIV infection.
Invariant NKT cells (iNKT cells) are innate lymphocytes that recognize lipid-derived Ags presented by the MHC class I–related protein CD1d. In this study, we analyzed the role of iNKT cells in the generation of Abs against HSV type 1 (HSV-1). In sera from healthy hman donors, we found a correlation between HSV-1–specific IgG titers and proportions of CD4+ iNKT cells. In HSV-1–infected iNKT cell–deficient mice, the amount of specific IgM and IgG Abs were significantly reduced compared with wild-type mice. Moreover, iNKT cell–deficient mice were unable to upregulate CD1d on B cells and failed to establish an IFN-γ–driven subtype profile of HSV-1–specific IgG Abs. In spleens of HSV-1–infected wild-type mice, the percentage of iNKT cells expressing CCR6, a marker for inflammatory iNKT cells secreting IFN-γ, was significantly decreased at 6 mo postinfection, suggesting that these cells were released from the spleen to other tissues. Finally, in vitro experiments showed that in the absence of CD1d-restricted cells, HSV-1 induced markedly lower IFN-γ production in splenocytes from naive mice. Taken together, our results indicate that iNKT cells shape the Ab response to HSV-1 infection and provide a basis for rational development of antiviral vaccines.
Background: Hantavirus infection in humans usually occurs via inhalation of infectious aerosolized excreta of rodents. Horizontal human-to-human transmission was reported only for the highly virulent Andes virus. The likelihood of vertical transmission and the clinical outcome of hantavirus infections in pregnancy is still unpredictable.Objectives: Very few data were published about the impact of hantaviruses in pregnancy. Here we present four cases of pregnant women infected by European hantaviruses. The risk of vertical virus transmission was investigated.Study design: Four pregnant women with clinical signs of acute hantavirus disease were investigated for hantavirus IgM and IgG after onset of clinical symptoms. Furthermore, the newborns were tested for presence of viral RNA and antibodies in cord blood and, if any parameter was found positive, 8-12 months after delivery.Results: Four women suffered from a hantavirus infection, two of them due to infection by Puumala virus and two by Dobrava-Belgrade virus. Three women delivered healthy babies by vaginal route and one woman by Caesarean section (week 28). In no case hantavirus RNA was detected in cord blood after delivery or in the 8-12 month old babies. Hantavirus IgG was detectable in the cord blood of 3 babies (but not in the preterm child); these antibodies disappeared after 8-12 months indicating a passive transfer of immunoglobulins. No child had any clinical sign of hantavirus infection.Conclusions: In this study, the absence of vertical hantavirus transmission was demonstrated for pregnant women with onset of hantavirus disease between gestation weeks 14 and 28. (C) 2012 Elsevier B.V. All rights reserved.
OBJECTIVE To examine the specificity of human papillomavirus (HPV) E6/E7 mRNA testing for intraepithelial precursor lesions and invasive carcinoma of the uterine cervix in 358 women and compare the results with those of the most widely used DNA technique. STUDY DESIGN For HPV E6/E7 mRNA testing an amplification assay was used. For DNA determination a hybridization assay was applied. Both techniques were used simultaneously in patients with normal morphology (150), cervical intraepithelial neoplasia (173) and invasive carcinoma of the cervix (35). RESULTS HPV DNA positivity rates were significantly higher than E6/E7 mRNA in women with normal morphology (21-7%), cervical intraepithelial neoplasia (CIN) 1 and 2 (75-43%), and CIN 3 (93-63%). In invasive cervical carcinoma, both methods tested equally high (94% vs. 97%). Considering that E6/E7 up-regulation represents the initial step in cervical carcinogenesis, it can be assumed that this test allows a more specific detection of lesions with a potential for progression. CONCLUSION HPV E6/E7 mRNA may serve as a more specific discriminator between transient cervical dysplasias and potentially progressive lesions. Accordingly, testing for high-risk HPV E6/E7 mRNA might reduce the psychologic burden associated with HPV-DNA testing.
Hepatitis D virus (HDV) infection is an important etiologic agent of fulminant hepatitis and may aggravate the clinical course of chronic hepatitis B infection resulting in cirrhosis and liver failure. This report describes the establishment of a real-time reverse transcriptase polymerase chain reaction method that allows the quantitative detection of HDV-1 and HDV-3 with a sensitivity in a linear range of 2 × 103 to 108 copies/mL. Additionally, the new assay provides the opportunity to distinguish HDV-1 from HDV-3 by a subsequent melting curve analysis, an important option because these HDV types are highly associated with severe clinical outcome. The results of the melting curve analysis of 42 HDV sequences obtained in this study and the phylogenetic analysis based on 139 full-length sequences from GenBank were consistent and showed that all sequences described here cluster within the HDV-1 clade. Therefore, this assay is useful for monitoring of antiviral treatment and molecular epidemiologic studies of HDV distribution.
Swine Hepatitis E virus (HEV) can be transmitted from pigs to humans causing hepatitis. A high prevalence of HEV in wild boar populations is reported for several European countries, but actual data for Germany are missing. During the hunting season from October to December 2007 liver, bile and blood samples were collected from wild boars in four different German regions. The samples were tested for HEV RNA by quantitative PCR (qPCR) and anti-HEV IgG antibodies by two different ELISAs and a Line immunoassay. A seroprevalence of 29.9% using ELISA and 26.2% in the Line immunoassay was determined. The seroprevalence rate varied greatly within the analyzed regions. However, qPCR analysis revealed a higher prevalence of 68.2% positive animals with regional differences. Surprisingly, also adult wild sows and wild boars were highly HEV positive by qPCR. Compared to liver and serum samples, bile samples showed a higher rate of positive qPCR results. Sequencing and phylogenetic analysis of a 969nt fragment within ORF 2 revealed that all isolates clustered within genotype 3 but differed in the subtype depending on the hunting spot. Isolates clustered within genotypes 3i, 3h, 3f and 3e. Within one population HEV isolates were closely related, but social groups of animals in close proximity might be infected with different subtypes. Two full-length genomes of subtypes 3i and 3e from two different geographic regions were generated. The wild boar is discussed as one of the main sources of human autochthonous infections in Germany.
BACKGROUND:Although Europe is supposed to be non-endemic for hepatitis E virus (HEV), locally acquired human cases are registered, and a relatively high prevalence for anti-HEV was found in blood donors in some European countries. Transfusion-transmitted infections by contaminated blood products were reported in Japan and sporadically in Europe. MATERIALS AND METHODS:Several samples from a plasma donor were screened with a highly sensitive quantitative HEV real-time polymerase chain reaction and the full-length genome was generated. Serology was performed with two different commercially available ELISA kits. RESULTS:The full-length genome sequence of human HEV was identified using samples from a plasma donor with acute self-limiting hepatitis. Plasma donated 2 weeks before onset of elevated liver enzyme levels was already positive for HEV RNA (10(4) copies/ml). High viraemia (10(6) copies/ml) correlated with the detection of anti-HEV IgM in the first blood sample with increased alanine transaminase levels. Phylogenetic analyses grouped the isolate within genotype 3, subtype 3f. CONCLUSION:The sequence analyses and the epidemiological data revealed that the plasma donor was most probably infected with a swine HEV. This case supports the ongoing discussion of an obligatory HEV nucleic acid testing of blood products for special recipient risk groups.
Background: The effectiveness of antiretroviral therapy is often limited by drugs that penetrate the blood-brain barrier poorly, providing effective systemic, but not central nervous system (CNS), treatment. The constant presence of HIV-1 in the CNS may be associated with immunoactivation leading secondarily to neurological impairment. The aim of our study was to investigate whether an antiretroviral regimen including abacavir (ABC) and AZT can be used to effectively suppress HIV viral load (VL) in the cerebrospinal fluid (CSF) and improve or maintain normal neuropsychological and neurophysiologic parameters.
Complex hepatitis B virus (HBV) variants with mutations in core promoter (Cp) plus deletions in the C gene and/or preS region--that are associated with development of liver cirrhosis in renal transplant recipients--show a drastically changed phenotype with altered transcription and disturbed surface and core protein expression. Here, we analyzed the replication phenotype of six different defective variant genomes, isolated from two patients, after co-transfection with HBV wild-type (wt) in varying proportions. Both in HuH7 and HepG2 cells, the variants showed enhanced replication and enrichment in the different transfected variant-wt mixtures. Contrary to artificial variants with only C gene deletions in wt context, the original complex variants as well as wt genomes carrying C gene and Cp mutations of the variants did mostly not suppress wt replication. Thus, the Cp mutations compensate the suppression of wt by C gene deletions and furthermore enhance the replication level.
Here we describe an acute Dobrava-Belgrade virus (DOBV) infection that presented as severe hemorrhagic fever with renal syndrome (HFRS) in an active-duty U.S. soldier. The infection was acquired in northern Kosovo in spring 2013. Amplification of DOBV genome segments directly from the patient's serum sample was successfully performed. Phylogenetic analysis demonstrated that the strain belong to DOBV genotype Dobrava and is closely related to strains circulating in Southeast Europe and Slovakia. Thus, our case confirms that DOBV genotype Dobrava is able to cause a severe form of HFRS, especially when compared to the other less pathogenic DOBV genotypes.