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Lin C, Ballinger KR, Khetani SR. The application of engineered liver tissues for novel drug discovery. Expert Opin Drug Discov 2015; 10:519-40. [PMID: 25840592 DOI: 10.1517/17460441.2015.1032241] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Drug-induced liver injury remains a major cause of drug attrition. Furthermore, novel drugs are being developed for treating liver diseases. However, differences between animals and humans in liver pathways necessitate the use of human-relevant liver models to complement live animal testing during preclinical drug development. Microfabrication tools and synthetic biomaterials now allow for the creation of tissue subunits that display more physiologically relevant and long-term liver functions than possible with declining monolayers. AREAS COVERED The authors discuss acellular enzyme platforms, two-dimensional micropatterned co-cultures, three-dimensional spheroidal cultures, microfluidic perfusion, liver slices and humanized rodent models. They also present the use of cell lines, primary liver cells and induced pluripotent stem cell-derived human hepatocyte-like cells in the creation of cell-based models and discuss in silico approaches that allow integration and modeling of the datasets from these models. Finally, the authors describe the application of liver models for the discovery of novel therapeutics for liver diseases. EXPERT OPINION Engineered liver models with varying levels of in vivo-like complexities provide investigators with the opportunity to develop assays with sufficient complexity and required throughput. Control over cell-cell interactions and co-culture with stromal cells in both two dimension and three dimension are critical for enabling stable liver models. The validation of liver models with diverse sets of compounds for different applications, coupled with an analysis of cost:benefit ratio, is important for model adoption for routine screening. Ultimately, engineered liver models could significantly reduce drug development costs and enable the development of more efficacious and safer therapeutics for liver diseases.
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Affiliation(s)
- Christine Lin
- Colorado State University, School of Biomedical Engineering , 200 W. Lake St, 1301 Campus Delivery, Fort Collins, CO 80523-1374 , USA
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Dockendorff C, Faloon PW, Pu J, Yu M, Johnston S, Bennion M, Penman M, Nieland TJF, Dandapani S, Perez JR, Munoz B, Palmer MA, Schreiber SL, Krieger M. Benzo-fused lactams from a diversity-oriented synthesis (DOS) library as inhibitors of scavenger receptor BI (SR-BI)-mediated lipid uptake. Bioorg Med Chem Lett 2015; 25:2100-5. [PMID: 25900219 DOI: 10.1016/j.bmcl.2015.03.073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 02/07/2023]
Abstract
We report a new series of 8-membered benzo-fused lactams that inhibit cellular lipid uptake from HDL particles mediated by Scavenger Receptor, Class B, Type I (SR-BI). The series was identified via a high-throughput screen of the National Institutes of Health Molecular Libraries Small Molecule Repository (NIH MLSMR), measuring the transfer of the fluorescent lipid DiI from HDL particles to CHO cells overexpressing SR-BI. The series is part of a previously reported diversity-oriented synthesis (DOS) library prepared via a build-couple-pair approach. Detailed structure-activity relationship (SAR) studies were performed with a selection of the original library, as well as additional analogs prepared via solution phase synthesis. These studies demonstrate that the orientation of the substituents on the aliphatic ring have a critical effect on activity. Additionally, a lipophilic group is required at the western end of the molecule, and a northern hydroxyl group and a southern sulfonamide substituent also proved to be optimal. Compound 2p was found to possess a superior combination of potency (av IC50=0.10μM) and solubility (79μM in PBS), and it was designated as probe ML312.
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Affiliation(s)
- Chris Dockendorff
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA; Department of Chemistry, Marquette University, PO Box 1881, Milwaukee, WI 53201-1881, USA.
| | - Patrick W Faloon
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Jun Pu
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Miao Yu
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Stephen Johnston
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Melissa Bennion
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Marsha Penman
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Thomas J F Nieland
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Sivaraman Dandapani
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - José R Perez
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Benito Munoz
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Michelle A Palmer
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Stuart L Schreiber
- Center for the Science of Therapeutics, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Broad Institute, 7 Cambridge Center, Cambridge, MA 02142, USA
| | - Monty Krieger
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
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Foquet L, Hermsen CC, Verhoye L, van Gemert GJ, Cortese R, Nicosia A, Sauerwein RW, Leroux-Roels G, Meuleman P. Anti-CD81 but not anti-SR-BI blocks Plasmodium falciparum liver infection in a humanized mouse model. J Antimicrob Chemother 2015; 70:1784-7. [PMID: 25656410 DOI: 10.1093/jac/dkv019] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/12/2015] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVES Plasmodium falciparum sporozoites, deposited in the skin by infected Anopheles mosquitoes taking a blood meal, cross the endothelium of skin capillaries and travel to the liver where they traverse Kupffer cells and hepatocytes to finally invade a small number of the latter. In hepatocytes, sporozoites replicate, differentiate and give rise to large numbers of merozoites that are released into the bloodstream where they invade red blood cells, thus initiating the symptomatic blood stage. Using in vitro systems and rodent models, it has been shown that the hepatocyte receptors CD81 and scavenger receptor type B class I (SR-BI) play a pivotal role during sporozoite invasion. We wanted to evaluate whether these two entry factors are genuine drug targets for the prevention of P. falciparum infection in humans. METHODS Immunodeficient mice of which the liver is largely repopulated by human hepatocytes were treated with monoclonal antibodies blocking either CD81 or SR-BI 1 day prior to challenge with infected mosquitoes. P. falciparum infection of the liver was demonstrated using a qPCR assay. RESULTS In human liver chimeric mice, an antibody directed against CD81 completely blocked P. falciparum sporozoite invasion while SR-BI-specific monoclonal antibodies did not influence in vivo infection. CONCLUSIONS These observations confirm the role of CD81 in liver-stage malaria and question that of SR-BI. CD81 might be a valuable drug target for the prevention of malaria.
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Affiliation(s)
- Lander Foquet
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
| | - Cornelus C Hermsen
- Radboud University Medical Center, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Lieven Verhoye
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
| | - Geert-Jan van Gemert
- Radboud University Medical Center, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | | | - Alfredo Nicosia
- CEINGE, Via Comunale Margherita, 484-538, 80131 Naples, Italy Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Corso Umberto I, 80138 Naples, Italy
| | - Robert W Sauerwein
- Radboud University Medical Center, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Geert Leroux-Roels
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
| | - Philip Meuleman
- Center for Vaccinology, Ghent University, De Pintelaan 185, 9000 Gent, Belgium
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Khetani SR, Berger DR, Ballinger KR, Davidson MD, Lin C, Ware BR. Microengineered liver tissues for drug testing. ACTA ACUST UNITED AC 2015; 20:216-50. [PMID: 25617027 DOI: 10.1177/2211068214566939] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Indexed: 01/09/2023]
Abstract
Drug-induced liver injury (DILI) is a leading cause of drug attrition. Significant and well-documented differences between animals and humans in liver pathways now necessitate the use of human-relevant in vitro liver models for testing new chemical entities during preclinical drug development. Consequently, several human liver models with various levels of in vivo-like complexity have been developed for assessment of drug metabolism, toxicity, and efficacy on liver diseases. Recent trends leverage engineering tools, such as those adapted from the semiconductor industry, to enable precise control over the microenvironment of liver cells and to allow for miniaturization into formats amenable for higher throughput drug screening. Integration of liver models into organs-on-a-chip devices, permitting crosstalk between tissue types, is actively being pursued to obtain a systems-level understanding of drug effects. Here, we review the major trends, challenges, and opportunities associated with development and implementation of engineered liver models created from primary cells, cell lines, and stem cell-derived hepatocyte-like cells. We also present key applications where such models are currently making an impact and highlight areas for improvement. In the future, engineered liver models will prove useful for selecting drugs that are efficacious, safer, and, in some cases, personalized for specific patient populations.
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Affiliation(s)
- Salman R Khetani
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, USA School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Dustin R Berger
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Kimberly R Ballinger
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Matthew D Davidson
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Christine Lin
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Brenton R Ware
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO, USA
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Susceptibility to Plasmodium yoelii preerythrocytic infection in BALB/c substrains is determined at the point of hepatocyte invasion. Infect Immun 2014; 83:39-47. [PMID: 25312960 DOI: 10.1128/iai.02230-14] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
After transmission by Anopheles mosquitoes, Plasmodium sporozoites travel to the liver, infect hepatocytes, and rapidly develop as intrahepatocytic liver stages (LS). Rodent models of malaria exhibit large differences in the magnitude of liver infection, both between parasite species and between strains of mice. This has been mainly attributed to differences in innate immune responses and parasite infectivity. Here, we report that BALB/cByJ mice are more susceptible to Plasmodium yoelii preerythrocytic infection than BALB/cJ mice. This difference occurs at the level of early hepatocyte infection, but expression levels of reported host factors that are involved in infection do not correlate with susceptibility. Interestingly, BALB/cByJ hepatocytes are more frequently polyploid; thus, their susceptibility converges on the previously observed preference of sporozoites to infect polyploid hepatocytes. Gene expression analysis demonstrates hepatocyte-specific differences in mRNA abundance for numerous genes between BALB/cByJ and BALB/cJ mice, some of which encode hepatocyte surface molecules. These data suggest that a yet-unknown receptor for sporozoite infection, present at elevated levels on BALB/cByJ hepatocytes and also polyploid hepatocytes, might facilitate Plasmodium liver infection.
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Abstract
Despite the tremendous hurdles presented by the complexity of the liver's structure and function, advances in liver physiology, stem cell biology and reprogramming, and the engineering of tissues and devices are accelerating the development of cell-based therapies for treating liver disease and liver failure. This State of the Art Review discusses both the near- and long-term prospects for such cell-based therapies and the unique challenges for clinical translation.
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Affiliation(s)
- Sangeeta N Bhatia
- Institute for Medical Engineering & Science at MIT, Department of Electrical Engineering and Computer Science, David H. Koch Institute at MIT, and the Howard Hughes Medical Institute, Cambridge, MA 02139, USA. Division of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA.
| | - Gregory H Underhill
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Kenneth S Zaret
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ira J Fox
- Department of Surgery, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, and McGowan Institute for Regenerative Medicine, Pittsburgh, PA 15224, USA
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Exploring Drug Targets in Isoprenoid Biosynthetic Pathway for Plasmodium falciparum. Biochem Res Int 2014; 2014:657189. [PMID: 24864210 PMCID: PMC4017727 DOI: 10.1155/2014/657189] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 02/07/2014] [Accepted: 02/07/2014] [Indexed: 12/28/2022] Open
Abstract
Emergence of rapid drug resistance to existing antimalarial drugs in Plasmodium falciparum has created the need for prediction of novel targets as well as leads derived from original molecules with improved activity against a validated drug target. The malaria parasite has a plant plastid-like apicoplast. To overcome the problem of falciparum malaria, the metabolic pathways in parasite apicoplast have been used as antimalarial drug targets. Among several pathways in apicoplast, isoprenoid biosynthesis is one of the important pathways for parasite as its multiplication in human erythrocytes requires isoprenoids. Therefore targeting this pathway and exploring leads with improved activity is a highly attractive approach. This report has explored progress towards the study of proteins and inhibitors of isoprenoid biosynthesis pathway. For more comprehensive analysis, antimalarial drug-protein interaction has been covered.
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Extensive differences in gene expression between symbiotic and aposymbiotic cnidarians. G3-GENES GENOMES GENETICS 2014; 4:277-95. [PMID: 24368779 PMCID: PMC3931562 DOI: 10.1534/g3.113.009084] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Coral reefs provide habitats for a disproportionate number of marine species relative to the small area of the oceans that they occupy. The mutualism between the cnidarian animal hosts and their intracellular dinoflagellate symbionts provides the nutritional foundation for coral growth and formation of reef structures, because algal photosynthesis can provide >90% of the total energy of the host. Disruption of this symbiosis (“coral bleaching”) is occurring on a large scale due primarily to anthropogenic factors and poses a major threat to the future of coral reefs. Despite the importance of this symbiosis, the cellular mechanisms involved in its establishment, maintenance, and breakdown remain largely unknown. We report our continued development of genomic tools to study these mechanisms in Aiptasia, a small sea anemone with great promise as a model system for studies of cnidarian–dinoflagellate symbiosis. Specifically, we have generated de novo assemblies of the transcriptomes of both a clonal line of symbiotic anemones and their endogenous dinoflagellate symbionts. We then compared transcript abundances in animals with and without dinoflagellates. This analysis identified >900 differentially expressed genes and allowed us to generate testable hypotheses about the cellular functions affected by symbiosis establishment. The differentially regulated transcripts include >60 encoding proteins that may play roles in transporting various nutrients between the symbiotic partners; many more encoding proteins functioning in several metabolic pathways, providing clues regarding how the transported nutrients may be used by the partners; and several encoding proteins that may be involved in host recognition and tolerance of the dinoflagellate.
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Ng S, March S, Galstian A, Hanson K, Carvalho T, Mota MM, Bhatia SN. Hypoxia promotes liver-stage malaria infection in primary human hepatocytes in vitro. Dis Model Mech 2013; 7:215-24. [PMID: 24291761 PMCID: PMC3917242 DOI: 10.1242/dmm.013490] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Homeostasis of mammalian cell function strictly depends on balancing oxygen exposure to maintain energy metabolism without producing excessive reactive oxygen species. In vivo, cells in different tissues are exposed to a wide range of oxygen concentrations, and yet in vitro models almost exclusively expose cultured cells to higher, atmospheric oxygen levels. Existing models of liver-stage malaria that utilize primary human hepatocytes typically exhibit low in vitro infection efficiencies, possibly due to missing microenvironmental support signals. One cue that could influence the infection capacity of cultured human hepatocytes is the dissolved oxygen concentration. We developed a microscale human liver platform comprised of precisely patterned primary human hepatocytes and nonparenchymal cells to model liver-stage malaria, but the oxygen concentrations are typically higher in the in vitro liver platform than anywhere along the hepatic sinusoid. Indeed, we observed that liver-stage Plasmodium parasite development in vivo correlates with hepatic sinusoidal oxygen gradients. Therefore, we hypothesized that in vitro liver-stage malaria infection efficiencies might improve under hypoxia. Using the infection of micropatterned co-cultures with Plasmodium berghei, Plasmodium yoelii or Plasmodium falciparum as a model, we observed that ambient hypoxia resulted in increased survival of exo-erythrocytic forms (EEFs) in hepatocytes and improved parasite development in a subset of surviving EEFs, based on EEF size. Further, the effective cell surface oxygen tensions (pO2) experienced by the hepatocytes, as predicted by a mathematical model, were systematically perturbed by varying culture parameters such as hepatocyte density and height of the medium, uncovering an optimal cell surface pO2 to maximize the number of mature EEFs. Initial mechanistic experiments revealed that treatment of primary human hepatocytes with the hypoxia mimetic, cobalt(II) chloride, as well as a HIF-1α activator, dimethyloxalylglycine, also enhance P. berghei infection, suggesting that the effect of hypoxia on infection is mediated in part by host-dependent HIF-1α mechanisms.
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Affiliation(s)
- Shengyong Ng
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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TREM2 governs Kupffer cell activation and explains belr1 genetic resistance to malaria liver stage infection. Proc Natl Acad Sci U S A 2013; 110:19531-6. [PMID: 24218563 DOI: 10.1073/pnas.1306873110] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Plasmodium liver stage infection is a target of interest for the treatment of and vaccination against malaria. Here we used forward genetics to search for mechanisms underlying natural host resistance to infection and identified triggering receptor expressed on myeloid cells 2 (TREM2) and MHC class II molecules as determinants of Plasmodium berghei liver stage infection in mice. Locus belr1 confers resistance to malaria liver stage infection. The use of newly derived subcongenic mouse lines allowed to map belr1 to a 4-Mb interval on mouse chromosome 17 that contains the Trem2 gene. We show that Trem2 expression in the nonparenchymal liver cells closely correlates with resistance to liver stage infection, implicating TREM2 as a mediator of the belr1 genetic effect. Trem2-deficient mice are more susceptible to liver stage infection than their WT counterparts. We found that Kupffer cells are the principle cells expressing TREM2 in the liver, and that Trem2(-/-) Kupffer cells display altered functional activation on exposure to P. berghei sporozoites. TREM2 expression in Kupffer cells contributes to the limitation of parasite expansion in isolated hepatocytes in vitro, potentially explaining the increased susceptibility of Trem2(-/-) mice to liver stage infection. The MHC locus was also found to control liver parasite burden, possibly owing to the expression of MHC class II molecules in hepatocytes. Our findings implicate unexpected Kupffer-hepatocyte cross-talk in the control Plasmodium liver stage infection and demonstrate that TREM2 is involved in host responses against the malaria parasite.
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61
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Targeting lipid biosynthesis and salvage in apicomplexan parasites for improved chemotherapies. Nat Rev Microbiol 2013; 11:823-35. [DOI: 10.1038/nrmicro3139] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Challenges in using cultured primary rodent hepatocytes or cell lines to study hepatic HDL receptor SR-BI regulation by its cytoplasmic adaptor PDZK1. PLoS One 2013; 8:e69725. [PMID: 23936087 PMCID: PMC3720616 DOI: 10.1371/journal.pone.0069725] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 06/12/2013] [Indexed: 12/15/2022] Open
Abstract
Background PDZK1 is a four PDZ-domain containing cytoplasmic protein that binds to a variety of membrane proteins via their C-termini and can influence the abundance, localization and/or function of its target proteins. One of these targets in hepatocytes in vivo is the HDL receptor SR-BI. Normal hepatic expression of SR-BI protein requires PDZK1 - <5% of normal hepatic SR-BI is seen in the livers of PDZK1 knockout mice. Progress has been made in identifying features of PDZK1 required to control hepatic SR-BI in vivo using hepatic expression of wild-type and mutant forms of PDZK1 in wild-type and PDZK1 KO transgenic mice. Such in vivo studies are time consuming and expensive, and cannot readily be used to explore many features of the underlying molecular and cellular mechanisms. Methodology/Principal Findings Here we have explored the potential to use either primary rodent hepatocytes in culture using 2D collagen gels with newly developed optimized conditions or PDZK1/SR-BI co-transfected cultured cell lines (COS, HEK293) for such studies. SR-BI and PDZK1 protein and mRNA expression levels fell rapidly in primary hepatocyte cultures, indicating this system does not adequately mimic hepatocytes in vivo for analysis of the PDZK1 dependence of SR-BI. Although PDZK1 did alter SR-BI protein expression in the cell lines, its influence was independent of SR-BI’s C-terminus, and thus is not likely to occur via the same mechanism as that which occurs in hepatocytes in vivo. Conclusions/Significance Caution must be exercised in using primary hepatocytes or cultured cell lines when studying the mechanism underlying the regulation of hepatic SR-BI by PDZK1. It may be possible to use SR-BI and PDZK1 expression as sensitive markers for the in vivo-like state of hepatocytes to further improve primary hepatocyte cell culture conditions.
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March S, Ng S, Velmurugan S, Galstian A, Shan J, Logan D, Carpenter A, Thomas D, Lee Sim BK, Mota MM, Hoffman SL, Bhatia SN. A microscale human liver platform that supports the hepatic stages of Plasmodium falciparum and vivax. Cell Host Microbe 2013; 14:104-15. [PMID: 23870318 PMCID: PMC3780791 DOI: 10.1016/j.chom.2013.06.005] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2012] [Revised: 01/15/2013] [Accepted: 06/05/2013] [Indexed: 01/21/2023]
Abstract
The Plasmodium liver stage is an attractive target for the development of antimalarial drugs and vaccines, as it provides an opportunity to interrupt the life cycle of the parasite at a critical early stage. However, targeting the liver stage has been difficult. Undoubtedly, a major barrier has been the lack of robust, reliable, and reproducible in vitro liver-stage cultures. Here, we establish the liver stages for both Plasmodium falciparum and Plasmodium vivax in a microscale human liver platform composed of cryopreserved, micropatterned human primary hepatocytes surrounded by supportive stromal cells. Using this system, we have successfully recapitulated the full liver stage of P. falciparum, including the release of infected merozoites and infection of overlaid erythrocytes, as well as the establishment of small forms in late liver stages of P. vivax. Finally, we validate the potential of this platform as a tool for medium-throughput antimalarial drug screening and vaccine development.
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Affiliation(s)
- Sandra March
- Health Sciences and Technology/Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States of America
- Broad Institute, Cambridge, MA, 02142, United States of America
| | - Shengyong Ng
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States of America
| | | | - Ani Galstian
- Health Sciences and Technology/Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States of America
- Broad Institute, Cambridge, MA, 02142, United States of America
| | - Jing Shan
- Health Sciences and Technology/Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States of America
| | - David Logan
- Broad Institute, Cambridge, MA, 02142, United States of America
| | - Anne Carpenter
- Broad Institute, Cambridge, MA, 02142, United States of America
| | - David Thomas
- Broad Institute, Cambridge, MA, 02142, United States of America
| | - B. Kim Lee Sim
- Sanaria Inc., Rockville, MD, 20850, United States of America
| | - Maria M. Mota
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | | | - Sangeeta N. Bhatia
- Health Sciences and Technology/Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States of America
- Howard Hughes Medical Institute, Koch Institute, and Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA; Department of Medicine, Brigham and Women’s Hospital, Boston, MA, 02115, United States of America
- Broad Institute, Cambridge, MA, 02142, United States of America
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Wang L, Qiu L, Zhou Z, Song L. Research progress on the mollusc immunity in China. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 39:2-10. [PMID: 22864285 DOI: 10.1016/j.dci.2012.06.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 06/17/2012] [Accepted: 06/27/2012] [Indexed: 05/27/2023]
Abstract
The economical and phylogenic importance of mollusc has led an increasing number of investigations giving emphasis to immune defense mechanism. This review discusses the advances in immunological study of mollusc in China, with special reference to dominant aquaculture species over the past decades. As an invertebrate group, molluscs lack adaptive immunity and consequently they have evolved sophisticated strategies of innate immunity for defense against pathogens. This review aims to present the various immunologically significant pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs), lectins, lipopolysaccharide and β-1, 3-glucan binding protein (LGBP), scavenger receptors (SRs) employed by mollucans. This work also highlights immune proteolytic cascade, TLR signaling pathway and an extensive repertoire of immune effectors including antimicrobial peptide, lysozyme, antioxidant enzyme and heat shock protein. Further, the review presents the preliminary progress made on the catecholaminergic neuroendocrine system in scallop and its immunomodulation function to throw light into neuroendocrine-immune regulatory network in lower invertebrates.
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Affiliation(s)
- Lingling Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
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65
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Risco-Castillo V, Son O, Franetich JF, Rubinstein E, Mazier D, Silvie O. [Plasmodium sporozoite entry pathways during malaria liver infection]. Biol Aujourdhui 2013; 207:219-29. [PMID: 24594570 DOI: 10.1051/jbio/2013021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Indexed: 11/14/2022]
Abstract
Plasmodium parasites, the causative agents of malaria, are transmitted by female Anopheles mosquitoes, which inject sporozoites into the skin of the host. The motile sporozoites enter the blood stream and, upon reaching the liver, transform into liver stages inside hepatocytes. The parasites enter host cells actively, using their actomyosin motor machinery to propel themselves through a specialized structure called junction. Penetration inside an invagination of the host cell plasma membrane results in the formation of the parasitophorous vacuole, which is essential for parasite further development. The mechanisms of sporozoite entry into host cells remain poorly understood at the molecular level. We reported for the first time a host factor required for infection of hepatocytes by Plasmodium sporozoites, the tetraspanin CD81, which also serves as a receptor for the hepatitis C virus. CD81 is involved at an early step of the infection, however no evidence for a direct interaction between CD81 and the parasite could be found. Although sporozoites can use several independent pathways to enter hepatocytes, depending on the parasite species and the host cell type, we showed that P. falciparum, the deadliest human malaria parasite, depends on CD81 to infect hepatocytes. We identified structural determinants in the CD81 large extracellular domain, and demonstrated that CD81 function is regulated by its molecular environment in specialized tetraspanin-enriched membrane microdomains. Based on these data we propose that CD81 acts indirectly during malaria infection, by interacting with other essential but still unidentified factor(s), possibly a receptor for the sporozoites, within specific microdomains of the hepatocyte plasma membrane.
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Affiliation(s)
- Veronica Risco-Castillo
- Inserm, UMR S 945, 91 boulevard de l'Hôpital, 75013 Paris, France - Université Pierre et Marie Curie-Paris VI, Faculté de Médecine Pierre et Marie Curie, 91 boulevard de l'Hôpital, 75013 Paris, France
| | - Olivia Son
- Inserm, UMR S 945, 91 boulevard de l'Hôpital, 75013 Paris, France - Université Pierre et Marie Curie-Paris VI, Faculté de Médecine Pierre et Marie Curie, 91 boulevard de l'Hôpital, 75013 Paris, France
| | - Jean-François Franetich
- Inserm, UMR S 945, 91 boulevard de l'Hôpital, 75013 Paris, France - Université Pierre et Marie Curie-Paris VI, Faculté de Médecine Pierre et Marie Curie, 91 boulevard de l'Hôpital, 75013 Paris, France
| | - Eric Rubinstein
- Inserm, U1004, Hôpital Paul Brousse, 14 avenue Paul Vaillant Couturier, 94807 Villejuif, France - Université Paris-Sud, Institut André Lwoff, 14 avenue Paul Vaillant Couturier, 94807 Villejuif, France
| | - Dominique Mazier
- Inserm, UMR S 945, 91 boulevard de l'Hôpital, 75013 Paris, France - Université Pierre et Marie Curie-Paris VI, Faculté de Médecine Pierre et Marie Curie, 91 boulevard de l'Hôpital, 75013 Paris, France - Assistance Publique-Hôpitaux de Paris, Groupe Hospitalier Pitié-Salpêtrière, Service Parasitologie-Mycologie, 75013 Paris, France
| | - Olivier Silvie
- Inserm, UMR S 945, 91 boulevard de l'Hôpital, 75013 Paris, France - Université Pierre et Marie Curie-Paris VI, Faculté de Médecine Pierre et Marie Curie, 91 boulevard de l'Hôpital, 75013 Paris, France
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Freimanis GL, Owusu-Ofori S, Allain JP. Hepatitis B virus infection does not significantly influence Plasmodium parasite density in asymptomatic infections in Ghanaian transfusion recipients. PLoS One 2012. [PMID: 23185500 PMCID: PMC3503819 DOI: 10.1371/journal.pone.0049967] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Areas endemic for malaria and Hepatitis B virus (HBV) infection largely overlap geographically. A recent study has suggested the existence of an interaction between the two pathogens in symptomatic co-infected individuals on the South-American continent. We examined this issue in a hyperendemic area for both pathogens in sub-Saharan Africa. METHODOLOGY AND FINDINGS Pre-transfusion samples from a retrospective cohort of 154 blood transfusion recipients were screened for both serological and molecular markers of HBV and Plasmodium genomes using species-specific nested PCR and quantitative real-time PCR. Thirty-seven individuals met exclusion criteria and were subsequently eliminated from further analysis. Of 117 participants, 90% of recipients exhibited evidence of exposure to HBV, 42% with HBsAg and/or HBV DNA and 48% anti-HBc reactive without detectable HBV DNA. Plasmodium genome prevalence by NAT was 50%. Parasitemic individuals were significantly younger than non-parasitemic individuals (P = 0.04). Parasitemia level was not significantly lower in individuals with HBV DNA positive infections compared to those with HBV DNA negative exposures. HBV DNA load was not significantly different in parasitemic and non-parasitemic individuals. CONCLUSION The data presented suggests that, in sub-Saharan Africa, asymptomatic co-infections with these two ubiquitous pathogens do not appear to significantly affect each other and evolve independently.
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Affiliation(s)
- Graham Lee Freimanis
- Division of Transfusion Medicine, Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | | | - Jean-Pierre Allain
- Division of Transfusion Medicine, Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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Lindner SE, Miller JL, Kappe SHI. Malaria parasite pre-erythrocytic infection: preparation meets opportunity. Cell Microbiol 2012; 14:316-24. [PMID: 22151703 DOI: 10.1111/j.1462-5822.2011.01734.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
For those stricken with malaria, the classic clinical symptoms are caused by the parasite's cyclic infection of red blood cells. However, this erythrocytic phase of the parasite's life cycle initiates from an asymptomatic pre-erythrocytic phase: the injection of sporozoites via the bite of a parasite-carrying Anopheline mosquito, and the ensuing infection of the liver. With the increased capabilities of studying liver stages in mice, much progress has been made elucidating the cellular and molecular basis of the parasite's progression through this bottleneck of its life cycle. Here we review relevant findings on how sporozoites prepare for infection of the liver and factors crucial to liver stage development as well as key host/parasite interactions.
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Affiliation(s)
- Scott E Lindner
- Seattle Biomedical Research Institute, Seattle, WA 98109, USA
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Graewe S, Stanway RR, Rennenberg A, Heussler VT. Chronicle of a death foretold:Plasmodiumliver stage parasites decide on the fate of the host cell. FEMS Microbiol Rev 2012; 36:111-30. [DOI: 10.1111/j.1574-6976.2011.00297.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2011] [Accepted: 06/22/2011] [Indexed: 11/27/2022] Open
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Chattopadhyay R, de la Vega P, Paik SH, Murata Y, Ferguson EW, Richie TL, Ooi GT. Early transcriptional responses of HepG2-A16 liver cells to infection by Plasmodium falciparum sporozoites. J Biol Chem 2011; 286:26396-405. [PMID: 21652718 PMCID: PMC3143603 DOI: 10.1074/jbc.m111.240879] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 06/01/2011] [Indexed: 11/06/2022] Open
Abstract
Invasion of hepatocytes by Plasmodium sporozoites deposited by Anopheles mosquitoes, and their subsequent transformation into infective merozoites is an obligatory step in the initiation of malaria. Interactions between the sporozoites and hepatocytes lead to a distinct, complex and coordinated cellular and systemic host response. Little is known about host liver cell response to sporozoite invasion, or whether it is primarily adaptive for the parasite, for the host, or for both. Our present study used gene expression profiling of human HepG2-A16 liver cells infected with Plasmodium falciparum sporozoites to understand the host early cellular events and factors influencing parasite infectivity and sporozoite development. Our results show that as early as 30 min following wild-type, non-irradiated sporozoite exposure, the expressions of at least 742 genes was selectively altered. These genes regulate diverse biological functions, such as immune processes, cell adhesion and communications, metabolism pathways, cell cycle regulation, and signal transduction. These functions reflect cellular events consistent with initial host cell defense responses, as well as alterations in host cells to sustain sporozoites growth and survival. Irradiated sporozoites gave very similar gene expression pattern changes, but direct comparative analysis between liver gene expression profiles caused by irradiated and non-irradiated sporozoites identified 29 genes, including glypican-3, that were specifically up-regulated only in irradiated sporozoites. Elucidating the role of this subset of genes may help identify the molecular basis for the irradiated sporozoites inability to develop intrahepatically, and their usefulness as an immunogen for developing protective immunity against pre-erythrocytic stage malaria.
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Affiliation(s)
- Rana Chattopadhyay
- From the Malaria Program, United States Military Malaria Vaccine Program
| | - Patricia de la Vega
- From the Malaria Program, United States Military Malaria Vaccine Program
- Walter Reed Army Institute of Research and
| | - Sun H. Paik
- Sun BioMedical Technologies Inc., Ridgecrest, California 93555
| | - Yoko Murata
- Sun BioMedical Technologies Inc., Ridgecrest, California 93555
| | | | - Thomas L. Richie
- From the Malaria Program, United States Military Malaria Vaccine Program
- the Naval Medical Research Center, Silver Spring, Maryland 20910-7500 and
| | - Guck T. Ooi
- Sun BioMedical Technologies Inc., Ridgecrest, California 93555
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Abstract
Malaria is a vector-borne infectious disease caused by unicellular parasites of the genus Plasmodium. These obligate intracellular parasites have the unique capacity to infect and replicate within erythrocytes, which are terminally differentiated host cells that lack antigen presentation pathways. Prior to the cyclic erythrocytic infections that cause the characteristic clinical symptoms of malaria, the parasite undergoes an essential and clinically silent expansion phase in the liver. By infecting privileged host cells, employing programs of complex life stage conversions and expressing varying immunodominant antigens, Plasmodium parasites have evolved mechanisms to downmodulate protective immune responses against ongoing and even future infections. Consequently, anti-malaria immunity develops only gradually over many years of repeated and multiple infections in endemic areas. The identification of immune correlates of protection among the abundant non-protective host responses remains a research priority. Understanding the molecular and immunological mechanisms of the crosstalk between the parasite and the host is a prerequisite for the rational discovery and development of a safe, affordable, and protective anti-malaria vaccine.
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Affiliation(s)
- Julius Clemence Hafalla
- Department of Immunology and Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
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Scavenger receptor class B type I and the hypervariable region-1 of hepatitis C virus in cell entry and neutralisation. Expert Rev Mol Med 2011; 13:e13. [PMID: 21489334 DOI: 10.1017/s1462399411001785] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hepatitis C virus (HCV) infection is a leading cause of chronic liver disease worldwide and represents a major public health problem. Viral attachment and entry - the first encounter of the virus with the host cell - are major targets of neutralising immune responses. Thus, a detailed understanding of the HCV entry process offers interesting opportunities for the development of novel therapeutic strategies. Different cellular or soluble host factors mediate HCV entry, and considerable progress has been made in recent years to decipher how they induce HCV attachment, internalisation and membrane fusion. Among these factors, the scavenger receptor class B type I (SR-BI/SCARB1) is essential for HCV replication in vitro, through its interaction with the HCV E1E2 surface glycoproteins and, more particularly, the HVR1 segment located in the E2 protein. SR-BI is an interesting receptor because HCV, whose replication cycle intersects with lipoprotein metabolism, seems to exploit some aspects of its physiological functions, such as cholesterol transfer from high-density lipoprotein (HDL), during cell entry. SR-BI is also involved in neutralisation attenuation and therefore could be an important target for therapeutic intervention. Recent results suggest that it should be possible to identify inhibitors of the interaction of HCV with SR-BI that do not impair its important physiological properties, as discussed in this review.
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Fioravanti J, Medina-Echeverz J, Berraondo P. Scavenger receptor class B, type I: a promising immunotherapy target. Immunotherapy 2011; 3:395-406. [DOI: 10.2217/imt.10.104] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Scavenger receptor class B, type I (SR-BI) is a crucial molecule in lipid metabolism, since the interaction of high-density lipoproteins (HDLs) with SR-BI is involved in reverse cholesterol transport and cholesterol efflux. Recent findings also underscore a critical role of SR-BI in antimicrobial and immune responses. SR-BI is not only highly expressed in liver and steroidogenic glands, but also in endothelial cells, macrophages and dendritic cells. SR-BI mainly mediates anti-inflammatory responses, which may be altered by dysfunctional HDLs produced in several diseases. Moreover, SR-BI has been involved in the capture and cross-presentation of antigens from viruses, bacteria and parasites. It thus works as a pattern-recognition receptor that interacts with both damage-associated molecular patterns and pathogen-associated molecular patterns. These new findings in the microbiology and immunology fields present SR-BI as an unexplored therapeutic target that warrants further basic and applied research.
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Affiliation(s)
- Jessica Fioravanti
- Division of Hepatology & Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra, Spain
| | - José Medina-Echeverz
- Division of Hepatology & Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra, Spain
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Ouwe-Missi-Oukem-Boyer O, Ndouo FST, Ollomo B, Mezui-Me-Ndong J, Noulin F, Lachard I, Ndong-Atome GR, Makuwa M, Roques P, Branger M, Preux PM, Mazier D, Bisser S. Hepatitis C virus infection may lead to slower emergence of P. falciparum in blood. PLoS One 2011; 6:e16034. [PMID: 21249226 PMCID: PMC3018426 DOI: 10.1371/journal.pone.0016034] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 12/06/2010] [Indexed: 11/19/2022] Open
Abstract
Background Areas endemic for Plasmodium falciparum, hepatitis B virus (HBV) and hepatitis C virus (HCV) overlap in many parts of sub-Saharan Africa. HBV and HCV infections develop in the liver, where takes place the first development stage of P. falciparum before its further spread in blood. The complex mechanisms involved in the development of hepatitis may potentially influence the development of the liver stage of malaria parasites. Understanding the molecular mechanisms of these interactions could provide new pathophysiological insights for treatment strategies in Malaria. Methodology We studied a cohort of 319 individuals living in a village where the three infections are prevalent. The patients were initially given a curative antimalarial treatment and were then monitored for the emergence of asexual P. falciparum forms in blood, fortnightly for one year, by microscopy and polymerase chain reaction. Principal Findings At inclusion, 65 (20.4%) subjects had detectable malaria parasites in blood, 36 (11.3%) were HBV chronic carriers, and 61 (18.9%) were HCV chronic carriers. During follow-up, asexual P. falciparum forms were detected in the blood of 203 patients. The median time to P. falciparum emergence in blood was respectively 140 and 120 days in HBV- and HBV+ individuals, and 135 and 224 days in HCV- and HCV+ individuals. HCV carriage was associated with delayed emergence of asexual P. falciparum forms in blood relative to patients without HCV infection. Conclusions This pilot study represents first tentative evidence of a potential epidemiological interaction between HBV, HCV and P. falciparum infections. Age is an important confounding factor in this setting however multivariate analysis points to an interaction between P. falciparum and HCV at the hepatic level with a slower emergence of P. falciparum in HCV chronic carriers. More in depth analysis are necessary to unravel the basis of hepatic interactions between these two pathogens, which could help in identifying new therapeutic approaches against malaria.
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Syder AJ, Lee H, Zeisel MB, Grove J, Soulier E, Macdonald J, Chow S, Chang J, Baumert TF, McKeating JA, McKelvy J, Wong-Staal F. Small molecule scavenger receptor BI antagonists are potent HCV entry inhibitors. J Hepatol 2011; 54:48-55. [PMID: 20932595 DOI: 10.1016/j.jhep.2010.06.024] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 06/10/2010] [Accepted: 06/14/2010] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND AIMS ITX 5061 is a clinical stage small molecule compound that promotes high-density lipoprotein (HDL) levels in animals and patients by targeting the scavenger receptor BI protein pathway. Since SR-BI is a known co-receptor for HCV infection, we evaluated these compounds for their effects on HCV entry. METHODS We obtained ITX 5061 and related compounds to characterize their interaction with SR-BI and effects on HCV entry and infection. RESULTS We confirmed that a tritium-labeled compound analog (ITX 7650) binds cells expressing SR-BI, and both ITX 5061 and ITX 7650 compete for HDL-mediated lipid transfer in an SR-BI dependent manner. Both molecules inhibit HCVcc and HCVpp infection of primary human hepatocytes and/or human hepatoma cell lines and have minimal effects on HCV RNA replication. Kinetic studies suggest that the compounds act at an early post-binding step. CONCLUSIONS These results suggest that the ITX compounds inhibit HCV infection with a mechanism of action distinct from other HCV therapies under development. Since ITX 5061 has already been evaluated in over 280 patients with good pharmacokinetic and safety profiles, it warrants proof-of-concept clinical studies in HCV infected patients.
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Affiliation(s)
- Andrew J Syder
- iTherX Pharmaceuticals, Inc., San Diego, CA 92191-0530, USA
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Labaied M, Jayabalasingham B, Bano N, Cha SJ, Sandoval J, Guan G, Coppens I. Plasmodium salvages cholesterol internalized by LDL and synthesized de novo in the liver. Cell Microbiol 2010; 13:569-86. [PMID: 21105984 DOI: 10.1111/j.1462-5822.2010.01555.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Our previous morphological studies illustrated the association of sterols with Plasmodium infecting hepatocytes. Because malaria parasites cannot synthesize sterols, they must scavenge these lipids from the host. In this paper, we have examined the source/s of sterols for intrahepatic Plasmodium and evaluated the importance of sterols for liver stage development. We show that Plasmodium continuously diverts cholesterol from hepatocytes until release of merozoites. Removal of plasma lipoproteins from the medium results in a 70% reduction of cholesterol content in hepatic merozoites but these parasites remain infectious in animals. Plasmodium salvages cholesterol that has been internalized by low-density lipoprotein but reduced expression of host low-density lipoprotein receptors by 70% does not influence liver stage burden. Plasmodium is also able to intercept cholesterol synthesized by hepatocytes. Pharmacological blockade of host squalene synthase or downregulation of the expression of this enzyme by 80% decreases by twofold the cholesterol content of merozoites without further impacting parasite development. These data enlighten that, on one hand, malaria parasites have moderate need of sterols for optimal development in hepatocytes and, on the other hand, they can adapt to survive in cholesterol-restrictive conditions by exploitation of accessible sterols derived from alternative sources in hepatocytes to maintain proper infectivity.
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Affiliation(s)
- Mehdi Labaied
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health and Malaria Research Institute, Baltimore, MD 21205, USA
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Maestre A, Muskus C, Duque V, Agudelo O, Liu P, Takagi A, Ntumngia FB, Adams JH, Sim KL, Hoffman SL, Corradin G, Velez ID, Wang R. Acquired antibody responses against Plasmodium vivax infection vary with host genotype for duffy antigen receptor for chemokines (DARC). PLoS One 2010; 5:e11437. [PMID: 20664684 PMCID: PMC2896388 DOI: 10.1371/journal.pone.0011437] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2009] [Accepted: 04/04/2010] [Indexed: 01/28/2023] Open
Abstract
Background Polymorphism of the Duffy Antigen Receptor for Chemokines (DARC) is associated with susceptibility to and the severity of Plasmodium vivax malaria in humans. P. vivax uses DARC to invade erythrocytes. Individuals lacking DARC are ‘resistant’ to P. vivax erythrocytic infection. However, susceptibility to P. vivax in DARC+ individuals is reported to vary between specific DARC genotypes. We hypothesized that the natural acquisition of antibodies to P. vivax blood stages may vary with the host genotype and the level of DARC expression. Furthermore, high parasitemia has been reported to effect the acquisition of immunity against pre-erythrocytic parasites. We investigated the correlation between host DARC genotypes and the frequency and magnitude of antibodies against P. vivax erythrocytic stage antigens. Methodology/Findings We assessed the frequencies and magnitudes of antibody responses against P. vivax and P. falciparum sporozoite and erythrocytic antigens in Colombian donors from malaria-endemic regions. The frequency and level of naturally-acquired antibodies against the P. vivax erythrocytic antigens merozoite surface protein 1 (PvMSP1) and Duffy binding protein (PvDBP) varied with the host DARC genotypes. Donors with one negative allele (FY*B/FY*Bnull and FY*A/FY*Bnull) were more likely to have anti-PvMSP1 and anti-PvDBP antibodies than those with two positive alleles (FY*B/FY*B and FY*A/FY*B). The lower IgG3 and IgG1 components of the total IgG response may account for the decreased responses to P. vivax erythrocytic antigens with FY*A/FY*B and FY*B/FY*B genotypes. No such association was detected with P. falciparum erythrocytic antigens, which does not use DARC for erythrocyte invasion. Conclusion/Significance Individuals with higher DARC expression, which is associated with higher susceptibility to P. vivax infection, exhibited low frequencies and magnitudes of P. vivax blood-stage specific antibody responses. This may indicate that one of the primary mechanisms by which P. vivax evades host immunity is through DARC indirectly down-regulating humoral responses against erythrocytic invasion and development.
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Affiliation(s)
- Amanda Maestre
- Grupo Salud y Comunidad, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Carlos Muskus
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Victoria Duque
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Olga Agudelo
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Pu Liu
- Seattle Biomedical Research Institute (SBRI), Seattle, Washington, United States of America
| | - Akihide Takagi
- Seattle Biomedical Research Institute (SBRI), Seattle, Washington, United States of America
| | | | - John H. Adams
- University of South Florida, Tampa, Florida, United States of America
| | - Kim Lee Sim
- Protein Potential LLC., Rockville, Maryland, United States of America
| | | | | | - Ivan D. Velez
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia
| | - Ruobing Wang
- Seattle Biomedical Research Institute (SBRI), Seattle, Washington, United States of America
- * E-mail:
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Jayabalasingham B, Menard R, Fidock DA. Recent insights into fatty acid acquisition and metabolism in malarial parasites. F1000 BIOLOGY REPORTS 2010; 2. [PMID: 20948809 PMCID: PMC2948358 DOI: 10.3410/b2-24] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The malarial parasite has a tremendous requirement for fatty acids during the replicative stages that take place in the mammalian host. A series of recent papers, discussed below, have revealed some of the mechanisms employed by the parasite to meet these demands.
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Affiliation(s)
- Bamini Jayabalasingham
- Department of Microbiology & Immunology, College of Physicians and Surgeons, Columbia UniversityRoom 1502, Hammer HSC, 701 W. 168th Street, New York, NY 10032USA
| | - Robert Menard
- Institut Pasteur, Unité de Biologie et Génétique du Paludisme28 rue du Dr Roux, Paris cedex 15, Paris 75724France
| | - David A Fidock
- Department of Microbiology & Immunology, College of Physicians and Surgeons, Columbia UniversityRoom 1502, Hammer HSC, 701 W. 168th Street, New York, NY 10032USA
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Wells TNC, Burrows JN, Baird JK. Targeting the hypnozoite reservoir of Plasmodium vivax: the hidden obstacle to malaria elimination. Trends Parasitol 2010; 26:145-51. [PMID: 20133198 DOI: 10.1016/j.pt.2009.12.005] [Citation(s) in RCA: 206] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Revised: 11/17/2009] [Accepted: 12/21/2009] [Indexed: 02/03/2023]
Abstract
Plasmodium vivax is the major species of malaria parasite outside Africa. It is especially problematic in that the infection can relapse in the absence of mosquitoes by activation of dormant hypnozoites in the liver. Medicines that target the erythrocytic stages of Plasmodium falciparum are also active against P. vivax, except where these have been compromised by resistance. However, the only clinical therapy against relapse of vivax malaria is the 8-aminoquinoline, primaquine. This molecule has the drawback of causing haemolysis in genetically sensitive patients and requires 14 days of treatment. New, safer and more-easily administered drugs are urgently needed, and this is a crucial gap in the broader malaria-elimination agenda. New developments in cell biology are starting to open ways to the next generation of drugs against hypnozoites. This search is urgent, given the time needed to develop a new medication.
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Aly ASI, Vaughan AM, Kappe SHI. Malaria parasite development in the mosquito and infection of the mammalian host. Annu Rev Microbiol 2009; 63:195-221. [PMID: 19575563 DOI: 10.1146/annurev.micro.091208.073403] [Citation(s) in RCA: 181] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Plasmodium sporozoites are the product of a complex developmental process in the mosquito vector and are destined to infect the mammalian liver. Attention has been drawn to the mosquito stages and pre-erythrocytic stages owing to recognition that these are bottlenecks in the parasite life cycle and that intervention at these stages can block transmission and prevent infection. Parasite progression in the Anopheles mosquito, sporozoite transmission to the mammalian host by mosquito bite, and subsequent infection of the liver are characterized by extensive migration of invasive stages, cell invasion, and developmental changes. Preparation for the liver phase in the mammalian host begins in the mosquito with an extensive reprogramming of the sporozoite to support efficient infection and survival. Here, we discuss what is known about the molecular and cellular basis of the developmental progression of parasites and their interactions with host tissues in the mosquito and during the early phase of mammalian infection.
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Affiliation(s)
- Ahmed S I Aly
- Seattle Biomedical Research Institute, Seattle, Washington 98109, USA.
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Charrin S, Yalaoui S, Bartosch B, Cocquerel L, Franetich JF, Boucheix C, Mazier D, Rubinstein E, Silvie O. The Ig domain protein CD9P-1 down-regulates CD81 ability to support Plasmodium yoelii infection. J Biol Chem 2009; 284:31572-8. [PMID: 19762465 DOI: 10.1074/jbc.m109.057927] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Invasion of hepatocytes by Plasmodium sporozoites is a prerequisite for establishment of a malaria natural infection. The molecular mechanisms underlying sporozoite invasion are largely unknown. We have previously reported that CD81 is required on hepatocytes for infection by Plasmodium falciparum and Plasmodium yoelii sporozoites. CD81 belongs to the tetraspanin superfamily of transmembrane proteins. By interacting with each other and with other transmembrane proteins, tetraspanins may play a role in the lateral organization of membrane proteins. In this study, we investigated the role of the two major molecular partners of CD81 in hepatocytic cells, CD9P-1/EWI-F and EWI-2, two transmembrane proteins belonging to a novel subfamily of immunoglobulin proteins. We show that CD9P-1 silencing increases the host cell susceptibility to P. yoelii sporozoite infection, whereas EWI-2 knock-down has no effect. Conversely, overexpression of CD9P-1 but not EWI-2 partially inhibits infection. Using CD81 and CD9P-1 chimeric molecules, we demonstrate the role of transmembrane regions in CD81-CD9P-1 interactions. Importantly, a CD9P-1 chimera that no longer associates with CD81 does not affect infection. Based on these data, we conclude that CD9P-1 acts as a negative regulator of P. yoelii infection by interacting with CD81 and regulating its function.
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Affiliation(s)
- Stéphanie Charrin
- INSERM, U602, Université Paris-Sud, Institut André Lwoff, F-94807 Villejuif, France
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82
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House BL, Hollingdale MR, Sacci JB, Richie TL. Functional immunoassays using an in-vitro malaria liver-stage infection model: where do we go from here? Trends Parasitol 2009; 25:525-33. [PMID: 19747878 DOI: 10.1016/j.pt.2009.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Revised: 06/26/2009] [Accepted: 08/07/2009] [Indexed: 01/23/2023]
Abstract
For more than 25 years, the ISI assay and ILSDA have been used to study the development of the malaria parasite in the liver, to discover and characterize sporozoite and liver-stage antigens, to support the development of malaria vaccine candidates, and to search for immunological correlates of protection in animals and in humans. Although both assays have been limited by low sporozoite invasion rates, significant biological variability, and the subjective nature of manually counting hepatocytes containing parasites as the read-out, they have nevertheless been useful tools for exploring parasite biology. This review describes the origin, application and current status of these assays, critically discusses the need for improvements, and explores the roles of these assays in supporting the development of an effective vaccine against Plasmodium falciparum malaria.
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Affiliation(s)
- Brent L House
- US Military Malaria Vaccine Program, Naval Medical Research Center/Walter Reed Army Institute of Research, Silver Spring, MD 21737, USA
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83
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Yáñez-Mó M, Barreiro O, Gordon-Alonso M, Sala-Valdés M, Sánchez-Madrid F. Tetraspanin-enriched microdomains: a functional unit in cell plasma membranes. Trends Cell Biol 2009; 19:434-46. [DOI: 10.1016/j.tcb.2009.06.004] [Citation(s) in RCA: 439] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 06/16/2009] [Accepted: 06/17/2009] [Indexed: 12/14/2022]
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84
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Areschoug T, Gordon S. Scavenger receptors: role in innate immunity and microbial pathogenesis. Cell Microbiol 2009; 11:1160-9. [DOI: 10.1111/j.1462-5822.2009.01326.x] [Citation(s) in RCA: 226] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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85
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Ejigiri I, Sinnis P. Plasmodium sporozoite-host interactions from the dermis to the hepatocyte. Curr Opin Microbiol 2009; 12:401-7. [PMID: 19608456 DOI: 10.1016/j.mib.2009.06.006] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Revised: 05/20/2009] [Accepted: 06/01/2009] [Indexed: 11/15/2022]
Abstract
Sporozoites are the infective stage of the malaria parasite. They are deposited in the skin by infected Anopheles mosquitoes and must penetrate cell barriers in the skin and liver sinusoid to reach their target cell, the hepatocyte, where they enter in a vacuole and begin development into the next life cycle stage, the exoerythrocytic form. Recent advances in our understanding of sporozoite biology in the dermal inoculation site, the role of cell traversal and the mechanism by which sporozoites productively invade hepatocytes will be highlighted in this review.
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Affiliation(s)
- Ijeoma Ejigiri
- Department of Medical Parasitology, New York University School of Medicine, New York, NY 10010, USA
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86
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Burlone ME, Budkowska A. Hepatitis C virus cell entry: role of lipoproteins and cellular receptors. J Gen Virol 2009; 90:1055-1070. [PMID: 19264629 DOI: 10.1099/vir.0.008300-0] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Hepatitis C virus (HCV), a major cause of chronic liver disease, is a single-stranded positive sense virus of the family Flaviviridae. HCV cell entry is a multi-step process, involving several viral and cellular factors that trigger virus uptake into the hepatocyte. Tetraspanin CD81, human scavenger receptor SR-BI, and tight junction molecules Claudin-1 and occludin are the main receptors that mediate HCV entry. In addition, the virus may use glycosaminoglycans and/or low density receptors on host cells as initial attachment factors. A unique feature of HCV is the dependence of virus replication and assembly on host cell lipid metabolism. Most notably, during HCV assembly and release from the infected cells, virus particles associate with lipids and very-low-density lipoproteins. Thus, infectious virus circulates in patient sera in the form of triglyceride-rich particles. Consequently, lipoproteins and lipoprotein receptors play an essential role in virus uptake and the initiation of infection. This review summarizes the current knowledge about HCV receptors, mechanisms of HCV cell entry and the role of lipoproteins in this process.
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Affiliation(s)
- Michela E Burlone
- University of Eastern Piedmont 'A. Avogadro', Department of Clinical and Experimental Medicine, Via Solaroli 17, 28100 Novara, Italy.,Pasteur Institute, Hepacivirus and Innate Immunity, 25/28 Rue du Dr Roux, 75724 Paris Cedex 15, France
| | - Agata Budkowska
- Pasteur Institute, Hepacivirus and Innate Immunity, 25/28 Rue du Dr Roux, 75724 Paris Cedex 15, France
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87
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88
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Dreux M, Dao Thi VL, Fresquet J, Guérin M, Julia Z, Verney G, Durantel D, Zoulim F, Lavillette D, Cosset FL, Bartosch B. Receptor complementation and mutagenesis reveal SR-BI as an essential HCV entry factor and functionally imply its intra- and extra-cellular domains. PLoS Pathog 2009; 5:e1000310. [PMID: 19229312 PMCID: PMC2636890 DOI: 10.1371/journal.ppat.1000310] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Accepted: 01/23/2009] [Indexed: 12/11/2022] Open
Abstract
HCV entry into cells is a multi-step and slow process. It is believed that the
initial capture of HCV particles by glycosaminoglycans and/or lipoprotein
receptors is followed by coordinated interactions with the scavenger receptor
class B type I (SR-BI), a major receptor of high-density lipoprotein (HDL), the
CD81 tetraspanin, and the tight junction protein Claudin-1, ultimately leading
to uptake and cellular penetration of HCV via low-pH endosomes.
Several reports have indicated that HDL promotes HCV entry through interaction
with SR-BI. This pathway remains largely elusive, although it was shown that HDL
neither associates with HCV particles nor modulates HCV binding to SR-BI. In
contrast to CD81 and Claudin-1, the importance of SR-BI has only been addressed
indirectly because of lack of cells in which functional complementation assays
with mutant receptors could be performed. Here we identified for the first time
two cell types that supported HCVpp and HCVcc entry upon ectopic SR-BI
expression. Remarkably, the undetectable expression of SR-BI in rat hepatoma
cells allowed unambiguous investigation of human SR-BI functions during HCV
entry. By expressing different SR-BI mutants in either cell line, our results
revealed features of SR-BI intracellular domains that influence HCV infectivity
without affecting receptor binding and stimulation of HCV entry induced by
HDL/SR-BI interaction. Conversely, we identified positions of SR-BI ectodomain
that, by altering HCV binding, inhibit entry. Finally, we characterized
alternative ectodomain determinants that, by reducing SR-BI cholesterol uptake
and efflux functions, abolish HDL-mediated infection-enhancement. Altogether, we
demonstrate that SR-BI is an essential HCV entry factor. Moreover, our results
highlight specific SR-BI determinants required during HCV entry and
physiological lipid transfer functions hijacked by HCV to favor infection. More than 180 million people are chronically infected by hepatitis C virus (HCV),
a leading cause of liver failure and cancer, stimulating the need to fully
define the biology of HCV infection for developing novel and effective
therapeutics. During the first steps of infection, the virus is taken up and
penetrates hepatocytes. HCV entry is thought to be a coordinated multi-step
process mediated by specific factors, including CD81, Claudin-1, and the
scavenger receptor BI (SR-BI). Whereas the involvement of CD81 and Claudin-1 was
demonstrated by rendering susceptible cells that are otherwise refractory, SR-BI
complementation assays were lacking, raising questions as to its functions
during HCV entry. Here, we identify one hepatoma rat cell line, in which SR-BI
complementation assay and targeted mutagenesis could be performed. We therefore
demonstrate that SR-BI is an essential HCV entry factor. Our results shed light
on SR-BI intracellular domain functions in HCV entry, and, further, emphasize
the remarkable capacity of HCV to hijack the lipid transfer function of SR-BI,
hence favoring infection.
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Affiliation(s)
- Marlène Dreux
- Université de Lyon, UCB-Lyon1, IFR128; INSERM, U758; Ecole
Normale Supérieure de Lyon, Lyon, France
| | - Viet Loan Dao Thi
- Université de Lyon, UCB-Lyon1, IFR128; INSERM, U758; Ecole
Normale Supérieure de Lyon, Lyon, France
| | - Judith Fresquet
- Université de Lyon, UCB-Lyon1, IFR128; INSERM, U758; Ecole
Normale Supérieure de Lyon, Lyon, France
| | | | | | - Géraldine Verney
- Université de Lyon, UCB-Lyon1, IFR128; INSERM, U758; Ecole
Normale Supérieure de Lyon, Lyon, France
| | - David Durantel
- Université de Lyon, UCB-Lyon1, IFR62; INSERM, U871; Hospices
civils de Lyon (HCL), Lyon, France
| | - Fabien Zoulim
- Université de Lyon, UCB-Lyon1, IFR62; INSERM, U871; Hospices
civils de Lyon (HCL), Lyon, France
| | - Dimitri Lavillette
- Université de Lyon, UCB-Lyon1, IFR128; INSERM, U758; Ecole
Normale Supérieure de Lyon, Lyon, France
| | - François-Loïc Cosset
- Université de Lyon, UCB-Lyon1, IFR128; INSERM, U758; Ecole
Normale Supérieure de Lyon, Lyon, France
- * E-mail:
| | - Birke Bartosch
- Université de Lyon, UCB-Lyon1, IFR128; INSERM, U758; Ecole
Normale Supérieure de Lyon, Lyon, France
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89
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Vaughan AM, Aly ASI, Kappe SHI. Malaria parasite pre-erythrocytic stage infection: gliding and hiding. Cell Host Microbe 2008; 4:209-18. [PMID: 18779047 DOI: 10.1016/j.chom.2008.08.010] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Accepted: 08/20/2008] [Indexed: 12/24/2022]
Abstract
In malaria, the red blood cell-infectious form of the Plasmodium parasite causes illness and the possible death of infected hosts. The initial infection in the liver caused by the mosquito-borne sporozoite parasite stage, however, causes little pathology and no symptoms. Nevertheless, pre-erythrocytic parasite stages are attracting passionate research efforts not least because they are the most promising targets for malaria vaccine development. Here, we review how the infectious sporozoite makes its way to the liver and subsequently develops within hepatocytes. We discuss the factors, both parasite and host, involved in the interactions that occur during this "silent" phase of infection.
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