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Pękacz M, Basałaj K, Młocicki D, Kamaszewski M, Carretón E, Morchón R, Wiśniewski M, Zawistowska-Deniziak A. Molecular insights and antibody response to Dr20/22 in dogs naturally infected with Dirofilaria repens. Sci Rep 2024; 14:12979. [PMID: 38839868 PMCID: PMC11153217 DOI: 10.1038/s41598-024-63523-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 05/29/2024] [Indexed: 06/07/2024] Open
Abstract
Subcutaneous dirofilariasis, caused by the parasitic nematode Dirofilaria repens, is a growing concern in Europe, affecting both dogs and humans. This study focused on D. repens Dr20/22, a protein encoded by an alt (abundant larval transcript) gene family. While well-documented in L3 larvae of other filariae species, this gene family had not been explored in dirofilariasis. The research involved cloning Dr20/22 cDNA, molecular characterization, and evaluating its potential application in the diagnosis of dirofilariasis. Although Real-Time analysis revealed mRNA expression in both adult worms and microfilariae, the native protein remained undetected in lysates from both developmental stages. This suggests the protein's specificity for L3 larvae and may be related to a process called SLTS (spliced leader trans-splicing), contributing to stage-specific gene expression. The specificity of the antigen for invasive larvae positions it as a promising early marker for dirofilariasis. However, ELISA tests using sera from infected and uninfected dogs indicated limited diagnostic utility. While further research is required, our findings contribute to a deeper understanding of the molecular and immunological aspects of host-parasite interactions and could offer insights into the parasite's strategies for evading the immune system.
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Affiliation(s)
- Mateusz Pękacz
- Division of Parasitology, Department of Preclinical Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, 02-786, Warsaw, Poland
| | - Katarzyna Basałaj
- Museum and Institute of Zoology, Polish Academy of Sciences, 00-818, Warsaw, Poland
| | - Daniel Młocicki
- Department of General Biology and Parasitology, Medical University of Warsaw, 02-004, Warsaw, Poland
| | - Maciej Kamaszewski
- Department of Ichthyology and Biotechnology in Aquaculture, Institute of Animal Sciences, Warsaw University of Life Sciences-SGGW, 02-786, Warsaw, Poland
| | - Elena Carretón
- Internal Medicine, Faculty of Veterinary Medicine, University of Las Palmas de Gran Canaria, Campus Arucas, Arucas, 35413, Las Palmas, Spain
| | - Rodrigo Morchón
- Zoonotic Diseases and One Health Group, Faculty of Pharmacy, University of Salamanca, Campus Miguel Unamuno, 37007, Salamanca, Spain
| | - Marcin Wiśniewski
- Division of Parasitology, Department of Preclinical Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, 02-786, Warsaw, Poland
| | - Anna Zawistowska-Deniziak
- Department of Immunology, Institute of Functional Biology and Ecology, Faculty of Biology, University of Warsaw, 02-095, Warsaw, Poland.
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Verma R, Kushwaha V, Pandey S, Thota JR, Vishwakarma P, Parmar N, Yadav PK, Tewari P, Kar S, Shukla PK, Murthy PK. Leishmania donovani molecules recognized by sera of filaria infected host facilitate filarial infection. Parasitol Res 2018; 117:2901-2912. [DOI: 10.1007/s00436-018-5981-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 06/19/2018] [Indexed: 12/31/2022]
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Harischandra H, Yuan W, Loghry HJ, Zamanian M, Kimber MJ. Profiling extracellular vesicle release by the filarial nematode Brugia malayi reveals sex-specific differences in cargo and a sensitivity to ivermectin. PLoS Negl Trop Dis 2018; 12:e0006438. [PMID: 29659599 PMCID: PMC5919703 DOI: 10.1371/journal.pntd.0006438] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 04/26/2018] [Accepted: 04/10/2018] [Indexed: 12/19/2022] Open
Abstract
The filarial nematode Brugia malayi is an etiological agent of Lymphatic Filariasis. The capability of B. malayi and other parasitic nematodes to modulate host biology is recognized but the mechanisms by which such manipulation occurs are obscure. An emerging paradigm is the release of parasite-derived extracellular vesicles (EV) containing bioactive proteins and small RNA species that allow secretion of parasite effector molecules and their potential trafficking to host tissues. We have previously described EV release from the infectious L3 stage B. malayi and here we profile vesicle release across all intra-mammalian life cycle stages (microfilariae, L3, L4, adult male and female worms). Nanoparticle Tracking Analysis was used to quantify and size EVs revealing discrete vesicle populations and indicating a secretory process that is conserved across the life cycle. Brugia EVs are internalized by murine macrophages with no preference for life stage suggesting a uniform mechanism for effector molecule trafficking. Further, the use of chemical uptake inhibitors suggests all life stage EVs are internalized by phagocytosis. Proteomic profiling of adult male and female EVs using nano-scale LC-MS/MS described quantitative and qualitative differences in the adult EV proteome, helping define the biogenesis of Brugia EVs and revealing sexual dimorphic characteristics in immunomodulatory cargo. Finally, ivermectin was found to rapidly inhibit EV release by all Brugia life stages. Further this drug effect was also observed in the related filarial nematode, the canine heartworm Dirofilaria immitis but not in an ivermectin-unresponsive field isolate of that parasite, highlighting a potential mechanism of action for this drug and suggesting new screening platforms for anti-filarial drug development.
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Affiliation(s)
- Hiruni Harischandra
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States of America
| | - Wang Yuan
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States of America
| | - Hannah J. Loghry
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States of America
| | - Mostafa Zamanian
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Michael J. Kimber
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, United States of America
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Kwarteng A, Ahuno ST. Immunity in Filarial Infections: Lessons from Animal Models and Human Studies. Scand J Immunol 2017; 85:251-257. [DOI: 10.1111/sji.12533] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 01/27/2017] [Indexed: 02/03/2023]
Affiliation(s)
- A. Kwarteng
- Department of Biochemistry and Biotechnology; Kwame Nkrumah University of Science Technology, PMB; Kumasi Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine (KCCR); KNUST, PMB; Kumasi Ghana
| | - S. T. Ahuno
- Department of Biochemistry and Biotechnology; Kwame Nkrumah University of Science Technology, PMB; Kumasi Ghana
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Myburgh E, Ritchie R, Goundry A, O’Neill K, Marchesi F, Devaney E. Attempts to Image the Early Inflammatory Response during Infection with the Lymphatic Filarial Nematode Brugia pahangi in a Mouse Model. PLoS One 2016; 11:e0168602. [PMID: 27992545 PMCID: PMC5161388 DOI: 10.1371/journal.pone.0168602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 12/02/2016] [Indexed: 11/30/2022] Open
Abstract
Helminth parasites remain a major constraint upon human health and well-being in many parts of the world. Treatment of these infections relies upon a very small number of therapeutics, most of which were originally developed for use in animal health. A lack of high throughput screening systems, together with limitations of available animal models, has restricted the development of novel chemotherapeutics. This is particularly so for filarial nematodes, which are long-lived parasites with a complex cycle of development. In this paper, we describe attempts to visualise the immune response elicited by filarial parasites in infected mice using a non-invasive bioluminescence imaging reagent, luminol, our aim being to determine whether such a model could be developed to discriminate between live and dead worms for in vivo compound screening. We show that while imaging can detect the immune response elicited by early stages of infection with L3, it was unable to detect the presence of adult worms or, indeed, later stages of infection with L3, despite the presence of worms within the lymphatic system of infected animals. In the future, more specific reagents that detect secreted products of adult worms may be required for developing screens based upon live imaging of infected animals.
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Affiliation(s)
- Elmarie Myburgh
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail: (EM); (ED); (FM)
| | - Ryan Ritchie
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Amy Goundry
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Kerry O’Neill
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Garscube Estate, Glasgow, United Kingdom
| | - Francesco Marchesi
- School of Veterinary Medicine, University of Glasgow, Garscube Estate, Glasgow
- * E-mail: (EM); (ED); (FM)
| | - Eileen Devaney
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Garscube Estate, Glasgow, United Kingdom
- * E-mail: (EM); (ED); (FM)
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Zamanian M, Fraser LM, Agbedanu PN, Harischandra H, Moorhead AR, Day TA, Bartholomay LC, Kimber MJ. Release of Small RNA-containing Exosome-like Vesicles from the Human Filarial Parasite Brugia malayi. PLoS Negl Trop Dis 2015; 9:e0004069. [PMID: 26401956 PMCID: PMC4581865 DOI: 10.1371/journal.pntd.0004069] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 08/18/2015] [Indexed: 01/28/2023] Open
Abstract
Lymphatic filariasis (LF) is a socio-economically devastating mosquito-borne Neglected Tropical Disease caused by parasitic filarial nematodes. The interaction between the parasite and host, both mosquito and human, during infection, development and persistence is dynamic and delicately balanced. Manipulation of this interface to the detriment of the parasite is a promising potential avenue to develop disease therapies but is prevented by our very limited understanding of the host-parasite relationship. Exosomes are bioactive small vesicles (30-120 nm) secreted by a wide range of cell types and involved in a wide range of physiological processes. Here, we report the identification and partial characterization of exosome-like vesicles (ELVs) released from the infective L3 stage of the human filarial parasite Brugia malayi. Exosome-like vesicles were isolated from parasites in culture media and electron microscopy and nanoparticle tracking analysis were used to confirm that vesicles produced by juvenile B. malayi are exosome-like based on size and morphology. We show that loss of parasite viability correlates with a time-dependent decay in vesicle size specificity and rate of release. The protein cargo of these vesicles is shown to include common exosomal protein markers and putative effector proteins. These Brugia-derived vesicles contain small RNA species that include microRNAs with host homology, suggesting a potential role in host manipulation. Confocal microscopy shows J774A.1, a murine macrophage cell line, internalize purified ELVs, and we demonstrate that these ELVs effectively stimulate a classically activated macrophage phenotype in J774A.1. To our knowledge, this is the first report of exosome-like vesicle release by a human parasitic nematode and our data suggest a novel mechanism by which human parasitic nematodes may actively direct the host responses to infection. Further interrogation of the makeup and function of these bioactive vesicles could seed new therapeutic strategies and unearth stage-specific diagnostic biomarkers.
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Affiliation(s)
- Mostafa Zamanian
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States of America
| | - Lisa M Fraser
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Prince N Agbedanu
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Hiruni Harischandra
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Andrew R Moorhead
- Department of Infectious Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Tim A Day
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
| | - Lyric C Bartholomay
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Michael J Kimber
- Department of Biomedical Sciences, Iowa State University, Ames, Iowa, United States of America
- * E-mail:
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Metenou S, Nutman TB. Regulatory T cell subsets in filarial infection and their function. Front Immunol 2013; 4:305. [PMID: 24137161 PMCID: PMC3786323 DOI: 10.3389/fimmu.2013.00305] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 09/13/2013] [Indexed: 01/11/2023] Open
Abstract
Filarial infections in humans are chronic infections that cause significant morbidity. The chronic nature of these infections with continuous antigen release is associated with a parasite-specific T cell hypo-responsiveness that may over time also affect the immune responses to bystander antigens. Previous studies have shown the filarial parasite antigen-specific T cells hypo-responsiveness is mediated by regulatory cytokines – IL-10 and TGF-β in particular. Recent studies have suggested that the modulated/regulated T cell responses associated with patent filarial infection may reflect an expansion of regulatory T cells (Tregs) that include both Tregs induced in peripheral circulation or pTregs and the thymus-derived Tregs or tTregs. Although much is known about the phenotype of these regulatory populations, the mechanisms underlying their expansion and their mode of action in filarial and other infections remain unclear. Nevertheless there are data to suggest that while many of these regulatory cells are activated in an antigen-specific manner the ensuing effectors of this activation are relatively non-specific and may affect a broad range of immune cells. This review will focus on the subsets and function of regulatory T cells in filarial infection.
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Affiliation(s)
- Simon Metenou
- Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institutes of Health , Bethesda, MD , USA
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Structural modelling studies and immunoprophylactic potential of Brugia malayiDEAD Box RNA helicase. Parasitology 2013; 140:1016-25. [DOI: 10.1017/s0031182013000322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
SUMMARYDEAD Box RNA helicases are essential enzymes that are involved in RNA metabolic processes such as transcription, pre-mRNA splicing, translation initiation and RNA decay. We have previously over-expressed and biochemically characterized an immunodominant cDNA clone encoding DEAD box RNA helicase (BmL3-Helicase) isolated by immunoscreening of the larval stage cDNA library ofBrugia malayi.In the current study, the 3D structure was determined and the immunoprophylactic efficacy of BmL3-Helicase was investigated by immunizingMastomys couchawith the recombinant protein and subsequently challenging withB. malayiinfective larvae. The immunization had an adverse outcome on the establishment of challenged larvae resulting in a 67·4% reduction in adult parasite recovery, a 86·7% decrease in the microfilarial density and profound sterility of the recovered female worms. The immune response thus generated was investigated by measuring the levels of specific antibodies including IgG subclasses, reactive oxygen species and cytokines.
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Dakshinamoorthy G, Samykutty AK, Munirathinam G, Reddy MV, Kalyanasundaram R. Multivalent fusion protein vaccine for lymphatic filariasis. Vaccine 2012; 31:1616-22. [PMID: 23036503 DOI: 10.1016/j.vaccine.2012.09.055] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2012] [Revised: 09/17/2012] [Accepted: 09/22/2012] [Indexed: 11/27/2022]
Abstract
Lymphatic filariasis affects approximately 3% of the whole world population. Mass drug administration is currently the major control strategy to eradicate this infection from endemic regions by year 2020. Combination drug treatments are highly efficient in controlling the infection. However, there are no effective vaccines available for human or animal lymphatic filariasis despite the identification of several subunit vaccines. Lymphatic filariasis parasites are multicellular organisms and potentially use multiple mechanisms to survive in the host. Therefore, there is a need to combine two or more vaccine candidate antigens to achieve the desired effect. In this study we combined three well characterized vaccine antigens of Brugia malayi, heat shock protein 12.6 (HSP12.6), Abundant Larval transcript-2 (ALT-2) and tetraspanin large extra cellular loop (TSP-LEL) as a multivalent fusion vaccine. Putative immune individuals carry circulating antibodies against all three antigens. Depletion of these antigen specific antibodies from the sera samples removed the ability of the sera to participate in the killing of B. malayi L3 in an antibody dependent cellular cytotoxicity (ADCC) mechanism. Vaccination trials in mice with a bivalent [HSP12.6+ALT-2 (HA), HSP12.6+TSP-LEL (HT) or TSP-LEL+ALT-2 (TA)] or trivalent [HSP12.6+ALT-2+TSP-LEL (HAT)] vaccines using DNA, protein or heterologous prime boost regimen showed that trivalent HAT vaccine either as protein alone or as heterologous prime boost vaccine could confer significant protection (95%) against B. malayi L3 challenge. Immune correlates of protection suggest a Th1/Th2 bias. These finding suggests that the trivalent HAT fusion protein is a promising prophylactic vaccine against lymphatic filariasis infection in human.
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Sreenivas K, Vijayan K, Babu S, Narayanan RB. Recombinant Brugia malayi pepsin inhibitor (rBm33) induced monocyte function and absence of apoptotic cell death: an in vitro study. Microb Pathog 2012; 53:19-27. [PMID: 22484090 DOI: 10.1016/j.micpath.2012.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 03/19/2012] [Accepted: 03/26/2012] [Indexed: 10/28/2022]
Abstract
The effect of recombinant Brugia malayi pepsin inhibitor (rBm33) on human monocytes/macrophages has been examined using THP-1 cells. THP-1 cells stimulated with rBm33 showed enhanced levels of expression of pro-inflammatory cytokines (IL-1β, TNF-α, IL-6) and diminished levels of IL-12, iNOS and anti-inflammatory cytokine (IL-10) expression suggesting the predominant features of Th1 response. Phorbol-12-myristate-13-acetate (PMA) treated THP-1 cells stimulated with rBm33 and subsequent incubation with GFP expressing Escherichia coli (E. coli) for 2 h enhanced the uptake of E. coli. Nitric oxide (NO) levels measured in the supernatants of these cultures did not show significant changes. Apoptotic studies with Peripheral Blood Mononuclear Cells (PBMCs) from normal individuals stimulated with rBm33 did not induce apoptosis of monocytes or lymphocytes. These observations suggest that rBm33 stimulates macrophages to induce Th1 response and does not promote apoptosis.
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Affiliation(s)
- Kirthika Sreenivas
- Centre for Biotechnology, Anna University, S.P road, Guindy, Chennai, Tamil Nadu 600025, India
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Cho-Ngwa F, Liu J, Lustigman S. The Onchocerca volvulus cysteine proteinase inhibitor, Ov-CPI-2, is a target of protective antibody response that increases with age. PLoS Negl Trop Dis 2010; 4:e800. [PMID: 20808763 PMCID: PMC2927424 DOI: 10.1371/journal.pntd.0000800] [Citation(s) in RCA: 19] [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: 09/28/2009] [Accepted: 07/23/2010] [Indexed: 11/18/2022] Open
Abstract
Background Despite considerable efforts, a suitable vaccine against Onchocerca volvulus infection has remained elusive. Herein, we report on the use of molecular tools to identify and characterize O. volvulus antigens that are possibly associated with the development of concomitant immunity in onchocerciasis. Methodology/Principal Findings Third-stage larvae (L3) and molting L3 (mL3) O. volvulus stage-specific cDNA libraries were screened with a pool of sera from chronically infected patients who had likely developed such immunity. The 87 immunoreactive clones isolated were grouped into 20 distinct proteins of which 12 had already been cloned and/or characterized before and 4 had been proven to be protective in a small O. volvulus animal model. One of these, onchocystatin (Ov-CPI-2), a previously characterized O. volvulus cysteine proteinase inhibitor was, overall, the most abundant clone recognized by the immune sera in both the L3 and mL3 cDNA libraries. To further characterize its association with protective immunity, we measured the IgG subclass and IgE class specific responses to the antigen in putatively immune (PI) and infected (INF) individuals living in a hyperendemic area in Cameroon. It appeared that both groups had similar IgG3 and IgE responses to the antigen, but the INF had significantly higher IgG1 and IgG4 responses than the PI individuals (p<0.05). In the INF group, the IgG3 levels increased significantly with the age of the infected individuals (r = 0.241; p<0.01). The IgG1 responses in the INF were high regardless of age. Notably, culturing L3 in vitro in the presence of anti-Ov-CPI-2 monospecific human antibodies and naïve neutrophils resulted in almost complete inhibition of molting of L3 to L4 and to cytotoxicity to the larvae. Conclusions/Significance These results add to the knowledge of protective immunity in onchocerciasis and support the possible involvement of anti-Ov-CPI-2 IgG1 and/or IgG3 cytophilic antibodies in the development of protective immunity in the PI and the INF. The results further support the consideration of Ov-CPI-2 as a leading target for an anti-L3 vaccine. Onchocerciasis is a chronic and highly debilitating disease of humans caused by a worm called Onchocerca volvulus. This worm can live in the human body for over 15 years. The disease affects mainly the skin and eyes and is the second leading infectious cause of blindness worldwide. There is currently no vaccine to prevent the infection. Available drugs can give short-term relief but cannot cure the infection. To prevent infection, a vaccine against the third-stage infective larva, L3, or the developing larva is required. These stages were shown to be the targets of protective immunity that develops in individuals who live in onchocerciasis endemic regions. One type of protective immunity has been shown to develop with age and is called concomitant immunity. In the present study, we have identified a number of larval antigens that may be associated with the development of such immunity. The most prominent of these antigens was Ov-CPI-2, also called onchocystatin, which had previously been shown to be a promising vaccine candidate. This antigen was further characterized and confirmed to be possibly also a target of immune protection that develops in the infected individuals with age and is referred to as concomitant immunity.
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Affiliation(s)
- Fidelis Cho-Ngwa
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America.
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Li BW, Rush AC, Mitreva M, Yin Y, Spiro D, Ghedin E, Weil GJ. Transcriptomes and pathways associated with infectivity, survival and immunogenicity in Brugia malayi L3. BMC Genomics 2009; 10:267. [PMID: 19527522 PMCID: PMC2708187 DOI: 10.1186/1471-2164-10-267] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Accepted: 06/15/2009] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Filarial nematode parasites cause serious diseases such as elephantiasis and river blindness in humans, and heartworm infections in dogs. Third stage filarial larvae (L3) are a critical stage in the life cycle of filarial parasites, because this is the stage that is transmitted by arthropod vectors to initiate infections in mammals. Improved understanding of molecular mechanisms associated with this transition may provide important leads for development of new therapies and vaccines to prevent filarial infections. This study explores changes in gene expression associated with the transition of Brugia malayi third stage larvae (BmL3) from mosquitoes into mammalian hosts and how these changes are affected by radiation. Radiation effects are especially interesting because irradiated L3 induce partial immunity to filarial infections. The underlying molecular mechanisms responsible for the efficacy of such vaccines are unkown. RESULTS Expression profiles were obtained using a new filarial microarray with 18, 104 64-mer elements. 771 genes were identified as differentially expressed in two-way comparative analyses of the three L3 types. 353 genes were up-regulated in mosquito L3 (L3i) relative to cultured L3 (L3c). These genes are important for establishment of filarial infections in mammalian hosts. Other genes were up-regulated in L3c relative to L3i (234) or irradiated L3 (L3ir) (22). These culture-induced transcripts include key molecules required for growth and development. 165 genes were up-regulated in L3ir relative to L3c; these genes encode highly immunogenic proteins and proteins involved in radiation repair. L3ir and L3i have similar transcription profiles for genes that encode highly immunogenic proteins, antioxidants and cuticle components. CONCLUSION Changes in gene expression that normally occur during culture under conditions that support L3 development and molting are prevented or delayed by radiation. This may explain the enhanced immunogenicity of L3ir. Gene Ontology and KEGG analyses revealed altered pathways between L3 types. Energy and "immune pathways" are up-regulated and may be needed for L3i invasion and survival, while growth and development are priorities for L3c. This study has improved our understanding of molecules involved in parasite invasion and immune evasion, potential targets of protective immunity, and molecules required for parasite growth and development.
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Affiliation(s)
- Ben-Wen Li
- Department of internal medicine, Washington University School of Medicine, St, Louis, MO 63110, USA.
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AdultBrugia malayimitochondrial and nuclear fractions impart Th1-associated sizeable protection against infective larval challenges inMastomys coucha. J Helminthol 2009; 83:83-95. [DOI: 10.1017/s0022149x08133582] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractProtective immunity to the subperiodic human filariid,Brugia malayi, was explored in the rodent host,Mastomys couchaafter vaccination with subcellular fractions derived from the adult stage of the parasite. The highest level of protection was conferred in animals vaccinated with the ‘mitochondria rich’ (MT) fraction, in which microfilaraemia and worm burden were markedly reduced by 67.2 and 65.9%, respectively, followed by the ‘nucleus rich’ (NR) fraction, showing reductions of 62 and 52.3%, respectively, over the non-immunized control group. Mastomys vaccinated with MT and NR, displayed a significant increase in the level of antigen-specific serum immunoglobulin G (IgG). The levels of IgG2a, IgG2b and IgM antibody isotypes were remarkably elevated in both the MT and NR immunized groups, while IgG1 and IgG3 levels were low. Apart from antibodies, both these fractions also led to marked antigen-specific lymphoproliferationin vitro, along with enhanced release of nitric oxide by peritoneal macrophages. There was an increased population of CD4+ and CD8a+T-cells in MT immunized animals, as measured by flow cytometry, accompanied by elevated levels of proinflammatory cytokines; interferon gamma (IFN-γ), tumour necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) in the culture supernatants of the activated splenocytes. The results suggest that both NR and MT contain proinflammatory molecules which evoke a protective Th1 type of immune response.
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Does resistance to filarial reinfections become leaky over time? Trends Parasitol 2008; 24:350-4. [DOI: 10.1016/j.pt.2008.04.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Revised: 04/09/2008] [Accepted: 04/24/2008] [Indexed: 11/17/2022]
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Li BW, Rush AC, Weil GJ, McCarter JP, Mitreva M. Brugia malayi: Effects of radiation and culture on gene expression in infective larvae. Mol Biochem Parasitol 2006; 149:201-7. [PMID: 16824625 DOI: 10.1016/j.molbiopara.2006.05.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2006] [Revised: 05/26/2006] [Accepted: 05/31/2006] [Indexed: 11/13/2022]
Abstract
Third-stage infective larvae (L3i) of Brugia malayi are developmentally arrested in mosquitoes but must quickly adapt to a new environment when they enter mammalian hosts to initiate infections. These changes can be studied by in vitro culture of L3 (L3c) under conditions that permit molting of L3-L4. Irradiated L3 (L3ir) have stunted growth and limited lifespan in mammalian hosts, and they induce high levels of immunity to challenge infections in animal models. This study explored differences in gene expression in L3i, L3c and L3ir by expressed sequence tag EST generation and qRT-PCR. 2506 ESTs generated from cDNA libraries constructed from L3i, L3c and L3ir were grouped into 1309 gene clusters. Despite extensive prior sampling from B. malayi (>22,000 ESTs in dbEST), 73% of the L3 clusters described here are novel. Sixty-three percentage of the clusters have homology to proteins from other species including 187 specific to nematodes and 141 that have to date only been described in non-nematode species. The transcript levels of 62 candidates for up- or down-regulation in L3i, L3c and L3ir based on EST frequencies were evaluated by qRT-PCR. Twenty-eight were confirmed to have > or = 3-fold differences in expression. Genes coding for proteins believed to be involved in establishment of infection, host adaptation and targets of protective immunity were confirmed to have higher expression in L3i than in L3c. Some of the genes that were down-regulated in L3c were highly expressed in L3ir. This study provides an improved description of the adaptations that accompany the transition from L3i to L3c and the special ability of L3ir to induce protective immunity.
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Affiliation(s)
- Ben-Wen Li
- Infectious Diseases Division, Campus Box 8051, Washington University School of Medicine, 660 S. Euclid Avenue, St. Louis, MO 63110, USA.
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16
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Monglo D, Njongmeta L, Musongong G, Ngassoum M, Nukenine E. Evaluation of Anthelmintic Potential of Ethanolic Plant Extracts from Northern Cameroon Against Eggs and Infective Larvae of Haemonchus contortus. ACTA ACUST UNITED AC 2006. [DOI: 10.3923/jbs.2006.426.433] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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17
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Rao R, Moussa H, Vanderwaal RP, Sampson E, Atkinson LJ, Weil GJ. Effects of gamma radiation on Brugia malayi infective larvae and their intracellular Wolbachia bacteria. Parasitol Res 2005; 97:219-27. [PMID: 15997407 DOI: 10.1007/s00436-005-1421-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2005] [Accepted: 05/10/2005] [Indexed: 10/25/2022]
Abstract
Prior studies have shown that irradiated filarial larvae are developmentally stunted but capable of inducing partial immunity to filariasis in animals. The mechanisms for these effects are poorly understood. Recent studies suggest that intracellular Wolbachia bacteria are necessary for the normal development, reproduction and survival of filarial nematodes. The purpose of this study was to examine the effects of irradiation on Wolbachia in Brugia malayi infective larvae (L3) and on L3 development. The L3 were exposed to 0, 25, 35, 45, 55, 65 or 75 krad of gamma irradiation from a (137) Cesium source and cultured in vitro at 37 degrees C in NCTC/IMDM medium with 10% FCS for 12 days. Irradiation prevented molting of L3 to the L4 stage in a dose-dependent manner. Electron microscopy studies showed that irradiation damaged Wolbachia (25 krad) or cleared them from worm tissues (45 krad). In addition, majority of the irradiated L3s failed to develop the L4 cuticle. Real-time PCR studies showed that irradiation reduced Wolbachia DNA in worm tissues. Parallel in vivo studies confirmed decreased development of irradiated L3 in jirds, with associated effects on Wolbachia. Jirds injected s.c with normal L3 developed antibodies to Wolbachia surface protein (wsp) shortly after the onset of microfilarial patency. In contrast, jirds injected with irradiated L3 did not develop microfilaremia or antibodies to wsp. Additional studies are needed to test the hypothesis that irradiation retards growth and development of filarial L3 by killing Wolbachia.
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Affiliation(s)
- R Rao
- Infectious Diseases Division, Department of Internal Medicine, School of Medicine, Washington University, Campus Box 8051, 660 S Euclid Ave, St. Louis, MO 63110, USA.
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18
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Duerr HP, Dietz K, Eichner M. Determinants of the eradicability of filarial infections: a conceptual approach. Trends Parasitol 2005; 21:88-96. [DOI: 10.1016/j.pt.2004.11.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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19
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Goodridge HS, Marshall FA, Wilson EH, Houston KM, Liew FY, Harnett MM, Harnett W. In vivo exposure of murine dendritic cell and macrophage bone marrow progenitors to the phosphorylcholine-containing filarial nematode glycoprotein ES-62 polarizes their differentiation to an anti-inflammatory phenotype. Immunology 2004; 113:491-8. [PMID: 15554927 PMCID: PMC1782600 DOI: 10.1111/j.1365-2567.2004.01993.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2004] [Accepted: 09/08/2004] [Indexed: 11/30/2022] Open
Abstract
We have previously shown in an in vitro study that the filarial nematode phosphorylcholine (PC)-containing glycoprotein ES-62 promotes a murine dendritic cell (DC) phenotype that induces T helper type 2 (Th2) responses. We now show that, in addition to directly priming Th2 responses, ES-62 can act to dampen down the pro-inflammatory DC responses elicited by lipopolysaccharide. Furthermore, we also demonstrate that murine DCs and macrophages derived ex vivo from bone marrow cells exposed in vivo to ES-62 by release from osmotic pumps are hyporesponsive to subsequent stimulation with lipopolysaccharide. These effects can be largely mimicked by exposure to the PC moiety of ES-62 conjugated to an irrelevant protein. The data we provide are, as far as we aware, the first to show that a defined pathogen product can modulate the developmental pathway of bone marrow cells of the immune system in vivo. Such a finding could have important implications for the use of pathogen products or their derivatives for immunotherapy.
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Affiliation(s)
- Helen S Goodridge
- Division of Immunology, Infection and Inflammation, University of Glasgow, Glasgow, United Kingdom
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20
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Subramanian S, Stolk WA, Ramaiah KD, Plaisier AP, Krishnamoorthy K, Van Oortmarssen GJ, Dominic Amalraj D, Habbema JDF, Das PK. The dynamics ofWuchereria bancroftiinfection: a model-based analysis of longitudinal data from Pondicherry, India. Parasitology 2004; 128:467-82. [PMID: 15180315 DOI: 10.1017/s0031182004004822] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This paper presents a model-based analysis of longitudinal data describing the impact of integrated vector management on the intensity ofWuchereria bancroftiinfection in Pondicherry, India. The aims of this analysis were (1) to gain insight into the dynamics of infection, with emphasis on the possible role of immunity, and (2) to develop a model that can be used to predict the effects of control. Using the LYMFASIM computer simulation program, two models with different types of immunity (anti-L3 larvae or anti-adult worm fecundity) were compared with a model without immunity. Parameters were estimated by fitting the models to data from 5071 individuals with microfilaria-density measurement before and after cessation of a 5-year vector management programme. A good fit, in particular of the convex shape of the age-prevalence curve, required inclusion of anti-L3 or anti-fecundity immunity in the model. An individual's immune-responsiveness was found to halve in ~10 years after cessation of boosting. Explanation of the large variation in Mf-density required considerable variation between individuals in exposure and immune responsiveness. The mean life-span of the parasite was estimated at about 10 years. For the post-control period, the models predict a further decline in Mf prevalence, which agrees well with observations made 3 and 6 years after cessation of the integrated vector management programme.
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Affiliation(s)
- S Subramanian
- Vector Control Research Centre (Indian Council of Medical Research), Indira Nagar, Medical Complex, Pondicherry-605 006, India.
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21
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Babayan S, Ungeheuer MN, Martin C, Attout T, Belnoue E, Snounou G, Rénia L, Korenaga M, Bain O. Resistance and susceptibility to filarial infection with Litomosoides sigmodontis are associated with early differences in parasite development and in localized immune reactions. Infect Immun 2004; 71:6820-9. [PMID: 14638768 PMCID: PMC308919 DOI: 10.1128/iai.71.12.6820-6829.2003] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In order to understand natural resistance to filariasis, we compared Litomosoides sigmodontis primary infection of C57BL/6 mice, which eliminate the worms before patency, and BALB/c mice, in which worms complete their development and produce microfilariae. Our analysis over the first month of infection monitoredmigration of the infective larvae from the lymph nodes to the pleural cavity, where the worms settle. Although immune responses from the mouse strains differed from the outset, the duration of lymphatic migration (4 days) and filarial recovery rates were similar, thus confirming that the proportion of larvae that develop in the host species upon infection is not influenced by host genetic variability. The majority of worms reached the adult stage in both mouse strains; however, worm growth and molting were retarded in resistant C57BL/6 mice. Surprisingly, the only immune responses detected at 60 h postinfection occurred in the susceptible mice and only upon stimulation of cells from lymph nodes draining the inoculation site with infective larva extract: massive production of interleukin-6 (IL-6) and IL-5 (the latter cytokine was previously suspected to have an effect on L. sigmodontis growth). However, between days 10 and 30 postinfection, extraordinarily high levels of type 1 and type 2 cytokines and expansion of pleural leukocyte infiltration were seen in the resistant C57BL/6 mice, explaining the destruction of worms later. Our results suggest that events early in the infection determine susceptibility or resistance to subsequent microfilarial production and a parasite strategy to use specific immune responses to its own benefit.
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Affiliation(s)
- Simon Babayan
- Parasitologie Comparée et Modèles Expérimentaux, Associé à INSERM U567, and Ecole Pratique des Hautes Etudes, Muséum National d'Histoire Naturelle, Paris, France
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22
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Babu S, Nutman TB. Proinflammatory Cytokines Dominate the Early Immune Response to Filarial Parasites. THE JOURNAL OF IMMUNOLOGY 2003; 171:6723-32. [PMID: 14662876 DOI: 10.4049/jimmunol.171.12.6723] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although the early human immune response to the infective-stage larvae (L3) of Brugia malayi has not been well-characterized in vivo (because of the inability to determine the precise time of infection), the consensus has been that it must involve a predominant Th2 environment. We have set up an in vitro system to study this early immune response by culturing PBMC from unexposed individuals with live L3 of B. malayi. After 24 h of culture, T cell responses were examined by flow cytometry and by quantitative real-time RT-PCR for multiple cytokines. T cells were activated early following exposure to L3 as indicated by up-regulation of surface markers CD69 and CD71. The frequency of T cells expressing proinflammatory Th1 cytokines (IFN-gamma, TNF-alpha, GM-CSF, IL-1alpha, and IL-8) but not Th2 cytokines (IL-4, IL-5, IL-6, IL-10, and IL-13) was significantly increased in response to L3. This T cell response occurred in both the CD4 and CD8 T cell compartment and was restricted to the effector/memory pool (CD45RO(+)). This T cell response was not due to LPS activity from the parasite or from its endosymbiont, Wolbachia; moreover, it required the presence of APC as well as direct contact with live L3. Real-time RT-PCR analysis of multiple cytokines in the T cells confirmed the increased expression of proinflammatory Th1 cytokines. Up-regulation of these cytokines suggests that the primary immune response to the live infective stage of the parasite is not predominantly Th2 in nature but rather dominated by a proinflammatory response.
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Affiliation(s)
- Subash Babu
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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23
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Duerr HP, Dietz K, Schulz-Key H, Büttner DW, Eichner M. Density-dependent parasite establishment suggests infection-associated immunosuppression as an important mechanism for parasite density regulation in onchocerciasis. Trans R Soc Trop Med Hyg 2003; 97:242-50. [PMID: 14584385 DOI: 10.1016/s0035-9203(03)90132-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The modulation of human immune response by filarial parasites has yielded contradictory experimental findings and attracted much controversy. We address the unresolved question of acquisition, establishment and accumulation of Onchocerca volvulus by using a modelling approach that relates computer simulations to cross-sectional data concerning parasite burdens in 913 West African onchocerciasis patients. It is shown that the acquisition of O. volvulus is not constant with host age; instead, the analysis of age profiles of parasite burdens strongly indicate the operation of immunosuppressive processes within the human host, associated with the presence of adult parasites or microfilariae. It is suggested that these processes suppress immunity against incoming infective larvae (L3), which themselves act as an immune modulating component once they have successfully overcome the barrier of concomitant immunity. Suppression of parasite-specific immunity leads to parasite establishment rates which increase along with the parasite burden, but which hardly depend on hyperendemic annual transmission potentials. Children, still immunocompetent due to low parasite burdens, acquire 0.1-0.5 adult female parasites per year, whereas older people, immunosuppressed due to high burdens, acquire 2-4 adult female parasites per year. Differences in parasite establishment between the forest and the savannah strains of O. volvulus are quantified and dynamic aspects of density-dependent parasite establishment discussed.
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Affiliation(s)
- H P Duerr
- Department of Medical Biometry, Institute of Tropical Medicine, University of Tübingen, Westbahnhofstr. 55, 72070 Tübingen, Germany.
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24
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Chirgwin SR, Elzer PH, Coleman SU, Nowling JM, Hagius SD, Edmonds MD, Klei TR. Infection outcome and cytokine gene expression in Brugia pahangi- infected gerbils (Meriones unguiculatus) sensitized with Brucella abortus. Infect Immun 2002; 70:5938-45. [PMID: 12379668 PMCID: PMC130301 DOI: 10.1128/iai.70.11.5938-5945.2002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Filarial infections have been associated with the development of a strongly polarized Th2 host immune response and a severe impairment of mitogen-driven proliferation and type 1 cytokine production in mice and humans. The role of this polarization in the development of the broad spectra of clinical manifestations of lymphatic filariasis is still unknown. Recently, data gathered from humans as well as from immunocompromised mouse models suggest that filariasis elicits a complex host immune response involving both Th1 and Th2 components. However, responses of a similar nature have not been reported in immunologically intact permissive models of Brugia infection. Brucella abortus-killed S19 was inoculated into the Brugia-permissive gerbil host to induce gamma interferon (IFN-gamma) production. Gerbils were then infected with B. pahangi, and the effect of the polarized Th1 responses on worm establishment and host cellular response was measured. Animals infected with both B. abortus and B. pahangi showed increased IFN-gamma and interleukin-10 (IL-10) and decreased IL-4 and IL-5 mRNA levels compared with those in animals infected with B. pahangi alone. These data suggest that the prior sensitization with B. abortus may induce a down regulation of the Th2 response associated with Brugia infection. This reduced Th2 response was associated with a reduced eosinophilia and an increased neutrophilia in the peritoneal exudate cells. The changes in cytokine and cellular environment did not inhibit the establishment of B. pahangi intraperitoneally. The data presented here suggest a complex relationship between the host immune response and parasite establishment and survival that cannot be simply ascribed to the Th1/Th2 paradigm.
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Affiliation(s)
- Sharon R Chirgwin
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, 70803, USA
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25
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Le Goff L, Lamb TJ, Graham AL, Harcus Y, Allen JE. IL-4 is required to prevent filarial nematode development in resistant but not susceptible strains of mice. Int J Parasitol 2002; 32:1277-84. [PMID: 12204227 DOI: 10.1016/s0020-7519(02)00125-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The murine Litomosoides sigmodontis model of filarial infection provides the opportunity to elucidate the immunological mechanisms that determine whether these nematode parasites can establish a successful infection or are rejected by the mammalian host. BALB/c mice are fully susceptible to L. sigmodontis infection and can develop patent infection, with the microfilarial stage circulating in the bloodstream. In contrast, mice on the C57BL background are largely resistant to the infection and never produce a patent infection. In this study, we used IL-4 deficient mice on the C57BL/6 background to address the role of IL-4 in the development of L. sigmodontis parasites in a resistant host. Two months after infection, adult worm recovery and the percentage of microfilaraemic mice in infected IL-4 deficient mice were comparable with those of the susceptible BALB/c mice while, as expected, healthy adults were not recovered from wild type C57BL/6 mice. The cytokine and antibody responses reveal that despite similar parasitology the two susceptible strains (BALB/c and IL-4 deficient C57BL/6) have markedly different immune responses: wild type BALB/c mice exhibit a strong Th2 immune response and the IL-4 deficient C57BL/6 mice exhibit a Th1 response. We also excluded a role for antibodies in resistance through infection of B-cell deficient C57BL/6 mice. Our data suggest that the mechanisms that determine parasite clearance in a resistant/non-permissive host are Th2 dependent but that in a susceptible/permissive host, the parasite can develop in the face of a Th2 dominated response.
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Affiliation(s)
- Laetitia Le Goff
- Institute of Cell, Animal and Population Biology, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, UK
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26
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MacDonald AJ, Turaga PSD, Harmon-Brown C, Tierney TJ, Bennett KE, McCarthy MC, Simonek SC, Enyong PA, Moukatte DW, Lustigman S. Differential cytokine and antibody responses to adult and larval stages of Onchocerca volvulus consistent with the development of concomitant immunity. Infect Immun 2002; 70:2796-804. [PMID: 12010965 PMCID: PMC127981 DOI: 10.1128/iai.70.6.2796-2804.2002] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The possibility of concomitant immunity and its potential mechanisms in Onchocerca volvulus infection were examined by analyzing cytokine and antibody responses to infective larval (third-stage larvae [L3] and molting L3 [mL3]), adult female worm (F-OvAg), and skin microfilaria (Smf) antigens in infected individuals in a region of hyperendemicity in Cameroon as a function of age. Peripheral blood mononuclear cell interleukin 5 (IL-5) responses to F-OvAg and Smf declined significantly with age (equivalent to years of exposure to O. volvulus). In contrast, IL-5 secretion in response to L3 and mL3 remained elevated with increasing age. Gamma interferon responses to L3, mL3, and F-OvAg were low or suppressed and unrelated to age, except for responses to Smf in older subjects. IL-10 levels were uniformly elevated, regardless of age, in response to L3, mL3, and F-OvAg but not to Smf, for which levels declined with age. A total of 49 to 60% of subjects had granulocyte-macrophage colony-stimulating factor responses to all O. volvulus antigens unrelated to age. Analysis of levels of stage-specific immunoglobulin G3 (IgG3) and IgE revealed a striking, age-dependent dissociation between antibody responses to larval antigens (L3 and a recombinant L3-specific protein, O. volvulus ALT-1) which were significantly increased or maintained with age and antibody responses to F-OvAg, which decreased. Levels of IgG1 to L3 and F-OvAg were elevated regardless of age, and levels of IgG4 increased significantly with age, although not to O. volvulus ALT-1, which may have unique L3-specific epitopes. Immunofluorescence staining of whole larvae showed that total anti-L3 immunoglobulin levels also increased with the age of the serum donor. The separate and distinct cytokine and antibody responses to adult and infective larval stages of O. volvulus which are age related are consistent with the acquisition of concomitant immunity in infected individuals.
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Affiliation(s)
- Angus J MacDonald
- Laboratory of Molecular Parasitology, New York Blood Center, New York, New York 10021, USA
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27
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Balmer P, Devaney E. NK T cells are a source of early interleukin-4 following infection with third-stage larvae of the filarial nematode Brugia pahangi. Infect Immun 2002; 70:2215-9. [PMID: 11895990 PMCID: PMC127851 DOI: 10.1128/iai.70.4.2215-2219.2002] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infection of C57BL/6 mice with the third-stage larvae of Brugia pahangi results in a rapid expansion of NK1.1(+) T cells in the spleen and draining lymph nodes. NK T cells produced interleukin-4 in the spleen within 24 h of infection, and these cells were CD4(-).
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Affiliation(s)
- Paul Balmer
- Department of Veterinary Parasitology, University of Glasgow, Glasgow G61 1QH, Scotland
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28
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Abstract
Although lymphatic filariasis remains among the major causes of disability among the tropical infectious diseases, dramatic advances have been made in the approach to its diagnosis, epidemiology and treatment, in our understanding of the molecular composition of the parasites that cause these infections, and in the factors underlying the pathology seen. Superimposing the tools of modern epidemiology, immunology, and molecular biology on field-based clinical trials has allowed the emergence of the concept of elimination of lymphatic filariasis. Much of the important new research emphasizes parasite development in the context of the host response, the importance of both the adult worm and other factors in the pathogenesis of lymphatic filarial disease, the role the Wolbachia endosymbiont holds as both a target for drug treatment and in inducing post-treatment reactions, and the various principles underlying the implementation of control programs.
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Affiliation(s)
- T B Nutman
- Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892-0425, USA.
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29
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Goodridge HS, Wilson EH, Harnett W, Campbell CC, Harnett MM, Liew FY. Modulation of macrophage cytokine production by ES-62, a secreted product of the filarial nematode Acanthocheilonema viteae. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:940-5. [PMID: 11441102 DOI: 10.4049/jimmunol.167.2.940] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Parasite survival and host health may depend on the ability of the parasite to modulate the host immune response by the release of immunomodulatory molecules. Excretory-secretory (ES)-62, one such well-defined molecule, is a major secreted protein of the rodent filarial nematode Acanthocheilonema viteae, and has homologues in human filarial nematodes. Previously we have shown that ES-62 is exclusively associated with a Th2 Ab response in mice. Here we provide a rationale for this polarized immune response by showing that the parasite molecule suppresses the IFN-gamma/LPS-induced production, by macrophages, of bioactive IL-12 (p70), a key cytokine in the development of Th1 responses. This suppression of the induction of a component of the host immune response extends to the production of the proinflammatory cytokines IL-6 and TNF-alpha, but not NO. The molecular mechanism underlying these findings awaits elucidation but, intriguingly, the initial response of macrophages to ES-62 is to demonstrate a low and transient release of these cytokines before becoming refractory to further release induced by IFN-gamma/LPS. The relevance of our observations is underscored by the finding that macrophages recovered from mice exposed to "physiological" levels of ES-62 by the novel approach of continuous release from implanted osmotic pumps in vivo were similarly refractory to release of IL-12, TNF-alpha, IL-6, but not NO, ex vivo. Therefore, our results suggest that exposure to ES-62 renders macrophages subsequently unable to produce Th1/proinflammatory cytokines. This likely contributes to the generation of immune responses with an anti-inflammatory Th2 phenotype, a well-documented feature of filarial nematode infection.
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MESH Headings
- Adjuvants, Immunologic/metabolism
- Adjuvants, Immunologic/physiology
- Animals
- Cell Survival/immunology
- Cells, Cultured
- Cytokines/biosynthesis
- Dipetalonema/immunology
- Dose-Response Relationship, Immunologic
- Drug Combinations
- Glycoproteins/administration & dosage
- Glycoproteins/metabolism
- Glycoproteins/physiology
- Helminth Proteins/administration & dosage
- Helminth Proteins/metabolism
- Helminth Proteins/physiology
- Immunosuppressive Agents/pharmacology
- Infusion Pumps, Implantable
- Interferon-gamma/antagonists & inhibitors
- Interferon-gamma/pharmacology
- Interleukin-12/antagonists & inhibitors
- Interleukin-12/biosynthesis
- Interleukin-12/genetics
- Interleukin-6/antagonists & inhibitors
- Interleukin-6/biosynthesis
- Lipopolysaccharides/antagonists & inhibitors
- Lipopolysaccharides/pharmacology
- Macrophage Activation/immunology
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/metabolism
- Male
- Mice
- Mice, Inbred BALB C
- Nitric Oxide/biosynthesis
- RNA, Messenger/antagonists & inhibitors
- RNA, Messenger/metabolism
- Tumor Necrosis Factor-alpha/antagonists & inhibitors
- Tumor Necrosis Factor-alpha/biosynthesis
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Affiliation(s)
- H S Goodridge
- Department of Immunology and Bacteriology, University of Glasgow, Western Infirmary, Dumbarton Road, Glasgow G11 6NT, United Kingdom
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