Efficient in vitro systems to study the life cycle of hepatitis C virus (HCV) were recently developed for JFH1 (genotype 2a), which has unique replication capacity in Huh7 cells. We developed 4a/JFH1 ...intergenotypic recombinants containing the structural genes (Core, E1, and E2), p7, and all or part of NS2 of the 4a prototype strain ED43 that, after transfection of Huh7.5 cells with RNA transcripts, produced infectious viruses. Compared with the J6/JFH control virus, production of viruses was delayed. However, efficient spread of infection and high HCV RNA and infectivity titers were obtained in serial passages. Sequence analysis of recovered viruses and subsequent reverse genetic studies revealed a vital dependence on one or two NS2 mutations, depending on the 4a/2a junction. Infectivity of ED43/JFH1 viruses was CD81 dependent. The genotype 4 cell culture systems permit functional analyses as well as drug and vaccine research on an increasingly important genotype in the Middle East, Africa, and Europe. We also developed genotype 1a intergenotypic recombinants from H77C with vital mutations in NS3. Using H77C/JFH1 and ED43/JFH1 viruses, we demonstrated high homologous neutralizing antibody titers in 1a and 4a patient sera, respectively. Furthermore, availability of JFH1 viruses with envelope proteins of the six major HCV genotypes permitted cross-neutralization studies; 1a and 4a serum cross-neutralized 1a, 4a, 5a, and 6a but not 2a and 3a viruses. Thus, the JFH1 intergenotypic recombinants will be of importance for future studies of HCV neutralization and accelerate the development of passive and active immunoprophylaxis.
Background. Recently, a hepatitis C virus (HCV) cell-culture system was developed that employed strain JFH1 (genotype 2a), and JFH1-based intra- and intergenotypic recombinants now permit functional ...studies of the structural genes (Core, E1, and E2), p7, and NS2 of genotypes 1–4. The goal was to adapt the system to employ genotype 5. Methods. Huh7.5 cells infected with SA13/JFH1, containing Core-NS2 of strain SA13 (genotype 5a), were monitored for Core expression and for supernatant infectivity and HCV-RNA titers. Adaptive mutations of SA13/JFH1 were identified by sequence analysis of recovered genomes and reverse-genetic studies. Receptor blockage was performed with anti-CD81 and anti-SR-BI. For neutralization experiments, SA13/JFH1 or JFH1-based viruses of other genotypes were incubated with patient sera. Results. SA13/JFH1 with NS2 and NS3 mutations yielded infectivity titers >105 TCID50/mL. Infection with SA13/JFH1 was inhibited by CD81 blocking and SR-BI blocking, respectively, and by preincubation with genotype 5a chronic-phase patient sera. Such sera had varying cross-genotype neutralization potential. However, preincubation and treatment with homologous neutralizing antibodies could not control SA13/JFH1 infection in culture. Conclusion. The SA13/JFH1 culture permits genotype 5a-specific studies of Core-NS2 function and interfering agents. The ability of HCV to spread in vivo during treatment with neutralizing antibodies was confirmed in vitro.
Background & Aims: Recently, full viral life cycle hepatitis C virus (HCV) cell culture systems were developed for strain JFH1 (genotype 2a) and an intragenotypic 2a/2a genome (J6/JFH). We aimed at ...exploiting the unique JFH1 replication characteristics to develop culture systems for genotype 3a, which has a high prevalence worldwide. Methods: Huh7.5 cells were transfected with RNA transcripts of an intergenotypic 3a/JFH1 recombinant with core, E1, E2, p7, and NS2 of the 3a reference strain S52, and released viruses were passaged. Cultures were examined for HCV core and/or NS5A expression (immunostaining), HCV RNA titers (real-time PCR), and infectivity titers (50% tissue culture infectious dose). The role of mutations identified by sequencing of recovered S52/JFH1 viruses was analyzed by reverse genetics studies. Results: S52/JFH1 and J6/JFH viruses passaged in Huh7.5 cells showed comparable growth kinetics and similar peak HCV RNA and infectivity titers. However, analysis of S52/JFH1 viruses identified 9 putative adaptive mutations in core, E2, p7, NS3, and NS5A. All 7 S52/JFH1 recombinants with an amino acid change in p7 combined with a change in NS3 or NS5A, but only 2 of 9 recombinants with individual mutations (in p7 and NS3, respectively) were fully viable without the requirement for additional mutations. The biological relevance of our system was shown by studying dependence of 3a/JFH1 infection on CD81, and its impact on distribution of intracellular lipids. Conclusions: We developed a robust intergenotypic recombinant cell culture system for HCV genotype 3a, providing a valuable tool for studies of 3a core-NS2 and related therapeutics.
Six major hepatitis C virus (HCV) genotypes and numerous subtypes have been described, and recently a seventh major genotype was discovered. Genotypes show significant molecular and clinical ...differences, such as differential response to combination therapy with interferon‐α and ribavirin. Recently, HCV research has been accelerated by cell culture systems based on the unique growth capacity of strain JFH1 (genotype 2a). By development of JFH1‐based intergenotypic recombinants containing Core, envelope protein 1 and 2 (E1, E2), p7, and nonstructural protein 2 (NS2) of genotype 6a and 7a strains, as well as subtype 1b and 2b strains, we have completed a panel of culture systems for all major HCV genotypes. Efficient growth in Huh7.5 cells depended on adaptive mutations for HK6a/JFH1 (6a/2a, in E1 and E2) and J4/JFH1 (1b/2a, in NS2 and NS3); viability of J8/JFH1 (2b/2a) and QC69/JFH1 (7a/2a) did not require adaptation. To facilitate comparative studies, we generated virus stocks of genotype 1–7 recombinants with infectivity titers of 103.7 to 105.2 50% tissue culture infectious dose/mL and HCV RNA titers of 107.0 to 107.9 IU/mL. Huh7.5 cultures infected with genotype 1–6 viruses had similar spread kinetics, intracellular Core, NS5A, and lipid amounts, and colocalization of Core and NS5A with lipids. Treatment with interferon‐α2b but not ribavirin or amantadine showed a significant antiviral effect. Infection with all genotypes could be blocked by specific antibodies against the putative coreceptors CD81 and scavenger receptor class B type I in a dose‐dependent manner. Finally, neutralizing antibodies in selected chronic phase HCV sera had differential effects against genotype 1–7 viruses. Conclusion: We completed and characterized a panel of JFH1‐based cell culture systems of all seven major HCV genotypes and important subtypes and used these viruses in comparative studies of antivirals, HCV receptor interaction, and neutralizing antibodies. (HEPATOLOGY 2009.)
Background. Recently, a hepatitis C virus (HCV) cell-culture system was developed that employed strain JFH1 (genotype 2a), and JFHl-based intra- and intergenotypic recombinants now permit functional ...studies of the structural genes (Core, El, and E2), p7, and NS2 of genotypes 1-4. The goal was to adapt the system to employ genotype 5. Methods. Huh7.5 cells infected with SA13/JFH1, containing Core-NS2 of strain SAB (genotype 5a), were monitored for Core expression and for supernatant infectivity and HCV-RNA titers. Adaptive mutations of SA13/JFH1 were identified by sequence analysis of recovered genomes and reverse-genetic studies. Receptor blockage was performed with anti-CD81 and anti-SR-BI. For neutralization experiments, SA13/JFH1 or JFH1-based viruses of other genotypes were incubated with patient sera. Results. SA13/JFH1 with NS2 and NS3 mutations yielded infectivity titers >10⁵ TCID₄₀/mL. Infection with SA13/JFH1 was inhibited by CD81 blocking and SR-BI blocking, respectively, and by preincubation with genotype 5a chronic-phase patient sera. Such sera had varying cross-genotype neutralization potential. However, preincubation and treatment with homologous neutralizing antibodies could not control SA13/JFH1 infection in culture. Conclusion. The SA13/JFH1 culture permits genotype 5a-specific studies of Core-NS2 function and interfering agents. The ability of HCV to spread in vivo during treatment with neutralizing antibodies was confirmed in vitro.
Background/Aim: The aim of this study was to examine the discriminatory power of quantitative EEG (qEEG) applying the statistical pattern recognition (SPR) method to separate Alzheimer's disease (AD) ...patients from elderly individuals without dementia and from other dementia patients. Methods: The participants were recruited from 6 Nordic memory clinics: 372 unselected patients mean age 71.7 years (SD 8.6), 54% women and 146 healthy elderly individuals mean age 66.5 years (SD 7.7), 60% women. After a standardized and comprehensive assessment, clinical diagnoses were made according to internationally accepted criteria by at least 2 clinicians. EEGs were recorded in a standardized way and analyzed independently of the clinical diagnoses, using the SPR method. Results: In receiver operating characteristic curve analyses, the qEEGs separated AD patients from healthy elderly individuals with an area under the curve (AUC) of 0.90, representing a sensitivity of 84% and a specificity of 81%. The qEEGs further separated patients with Lewy body dementia or Parkinson's disease dementia from AD patients with an AUC of 0.9, a sensitivity of 85% and a specificity of 87%. Conclusion: qEEG using the SPR method could be a useful tool in dementia diagnostic workup.
•SMI patients have higher plasma levels of IL-18, IL-18BPA, IL-18R1 relative to CTRL.•Gene expression of NLRP3 and NLRC4 is higher in the blood of SMI patients vs CTRL.•A cholesterol dyslipidemia ...pattern is present in the blood of patients with SMI.•Correlations found between cholesterol types and expression of IL-18 system in SMI.
Schizophrenia (SCZ) and bipolar disorder (BD) are severe mental illnesses (SMI) that are part of a psychosis continuum, and dysregulated innate immune responses have been suggested to be involved in their pathophysiology. However, disease-specific immune mechanisms in SMI are not known yet. Recently, dyslipidemia has been linked to systemic inflammasome activation, and elevated atherogenic lipid ratios have been shown to correlate with circulating levels of inflammatory biomarkers in SMI. It is, however, not yet known if increased systemic cholesterol load leads to inflammasome activation in these patients.
We tested the hypothesis that patients with SCZ and BD display higher circulating levels compared to healthy individuals of key members of the IL-18 system using a large patient cohort (n = 1632; including 737 SCZ and 895 BD), and healthy controls (CTRL; n = 1070). In addition, we assessed associations with coronary artery disease risk factors in SMI, focusing on relevant inflammasome-related, neuroendocrine, and lipid markers.
We report higher baseline levels of circulating IL-18 system components (IL-18, IL-18BPA, IL-18R1), and increased expression of inflammasome-related genes (NLRP3 and NLRC4) in the blood of patients relative to CTRL. We demonstrate a cholesterol dyslipidemia pattern in psychotic disorders, and report correlations between levels of blood cholesterol types and the expression of inflammasome system elements in SMI.
Based on these results, we suggest a role for inflammasome activation/dysregulation in SMI. Our findings further the understanding of possible underlying inflammatory mechanisms and may expose important therapeutic targets in SMI.
The capacity of ecosystems to deliver essential services to society is already under stress. The additional stresses imposed by climate change in the coming years will require extraordinary ...adaptation. We need to track the changing status of ecosystems, deepen our understanding of the biological underpinnings for ecosystem service delivery and develop new tools and techniques for maintaining and restoring resilient biological and social systems. We will be building on an ecosystem foundation that has been radically compromised during the past half century. Most rivers have been totally restructured, oceans have been severely altered and depleted, coral reefs are near the tipping point of disappearing as functional ecosystems, over half of the land surface is devoted to livestock and crop agriculture, with little consideration for the ecosystem services that are being lost as a consequence, some irrevocably so. We have already seen many regime shifts, or tipping points, due to human activity, even before the onset of measurable climate change impacts on ecosystems. Climate change, caused mainly by anthropogenic greenhouse gas emissions, will disrupt our ecosystem base in new ways. Already we are seeing widespread signs of change. Species behaviors are altering and disrupting mutualisms of long standing. We are seeing extinctions within vulnerable habitats and conditions where migrations are necessary for survival but where often there are no pathways available for successful movement in the fragmented world of today. These challenges represent an extraordinary threat to society and a call for urgent attention by the scientific community.
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