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Abuzeid AMI, Hefni MM, Huang Y, He L, Zhuang T, Li G. Immune pathogenesis in pigeons during experimental Prohemistomum vivax infection. Front Vet Sci 2022; 9:974698. [PMID: 36187827 PMCID: PMC9516004 DOI: 10.3389/fvets.2022.974698] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/11/2022] [Indexed: 11/13/2022] Open
Abstract
Prohemistomum vivax is a small trematode belonging to the family Cyathocotylidae, infecting fish-eating birds and mammals, including humans. However, no data on molecular identification and immune pathogenesis are available, challenging effective diagnostic and therapeutic interventions. Here, we identified P. vivax based on combined morphological and molecular data and examined histopathological lesions and the differential cytokines expression in experimentally infected pigeons. Pigeons were orally infected with 500 prohemistomid metacercariae. Intestinal and spleen tissues were harvested 2, 4, 7, 14, 21, and 28 days post-infection (dpi). Gene expression levels of eleven cytokines (IL-1, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-15, IL-18, IFN-γ, and TGF-β3) were assessed using quantitative reverse-transcription PCR (RT-qPCR). We identified the recovered flukes as Prohemistomum vivax based on morphological features and the sequence and phylogenetic analysis of the internal transcribed spacer 1 (ITS1), 5.8 ribosomal RNA, and ITS2 region. Histopathological lesions were induced as early as 2 dpi, with the intensity of villi atrophy and inflammatory cell infiltration increasing as the infection progressed. An early immunosuppressive state (2 and 4 dpi), with TGF-β3 overexpression, developed to allow parasite colonization. A mixed Th1/Th2 immune response (overexpressed IFN-γ, IL-12, IL-2, IL-4, and IL-5) was activated as the infection progressed from 7 to 28 dpi. Inflammatory cytokines (IL-1, IL-6, IL-18, and IL-15) were generally overexpressed at 7–28 dpi, peaking at 7 or 14 dpi. The upregulated Treg IL-10 expression peaking between 21 and 28 dpi might promote the Th1/Th2 balance and immune homeostasis to protect the host from excessive tissue pathology and inflammation. The intestine and spleen expressed a significantly different relative quantity of cytokines throughout the infection. To conclude, our results presented distinct cytokine alteration throughout P. vivax infection in pigeons, which may aid in understanding the immune pathogenesis and host defense mechanism against this infection.
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Affiliation(s)
- Asmaa M. I. Abuzeid
- Guangdong Provincial Key Laboratory of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Department of Parasitology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, Egypt
| | - Mahmoud M. Hefni
- Institute of Biotechnology for Postgraduates Studies and Researches, Suez Canal University, Ismailia, Egypt
- Mahmoud M. Hefni
| | - Yue Huang
- Guangdong Provincial Key Laboratory of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Long He
- Guangdong Provincial Key Laboratory of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Tingting Zhuang
- Guangdong Provincial Key Laboratory of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Guoqing Li
- Guangdong Provincial Key Laboratory of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- *Correspondence: Guoqing Li
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Tuo W, Zarlenga D, Bakshi M, Vinyard B. Repeated, drug-truncated infections with Ostertagia ostertagi elicit strong humoral and cell-mediated immune responses and confer partial protection in cattle. Vet Parasitol 2021; 296:109510. [PMID: 34217073 DOI: 10.1016/j.vetpar.2021.109510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 06/23/2021] [Accepted: 06/24/2021] [Indexed: 10/21/2022]
Abstract
Bovine ostertagiasis causes significant production losses to the cattle industry. Protective immunity induced by natural infection is slow to develop and anthelmintic resistance is rapidly developing. There is a need to advance alternatives for control of gastrointestinal nematode parasites. The present study investigated the effects of repeated, drug-truncated infections (rDTI) on development of protective immunity and attenuation of a challenge infection by O. ostertagi. Helminth-free calves were randomly assigned to either a rDTI or a control group (n = 5). The rDTI group received daily oral infections of 5000 Ostertagia L3 for 5 consecutive days, then were drug-treated on 14 and 15 days post infection (dpi), to attenuate O. ostertagi at the late fourth larval (L4) through young adult stages. DTI was repeated 3 weeks after the drug treatment. A total of 5 DTIs were administered to the DTI-treated animals. Non-DTI-treated, control animals received tap water as infection control. All animals were drug-treated at the same time. Animals were challenge-infected 4 weeks following the final round of rDTI. The results show that eggs per gram of feces (EPG) in the rDTI group were significantly reduced (P < 0.05) from 21 to 39 dpi, with an overall reduction in cumulative EPG. The control group exhibited reduced (P = 0.0564) average weight gains when compared to those of the rDTI group during weeks 4-5 post infection, a period coinciding with peak EPG output of control animals. Antigen-specific IgG, IgE and IgA responses were detected after the 2nd DTI, and stronger antibody recall responses were elicited by challenge infection. High levels of antigen-specific peripheral blood mononuclear cell (PBMC)/T cell proliferation to whole worm and excretory-secretory (ES) antigens were detected in rDTI-treated animals. These data indicate that partial protective immunity against ostertagiasis, involving cell-mediated and humoral responses, can be attained by rDTI which allowed for maximal antigen exposure from staggered parasitic developmental stages. The data suggest that rDTI can be used as a model to study host-parasite interactions and identify parasite antigens responsible for eliciting host protective immune responses.
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Affiliation(s)
- Wenbin Tuo
- Animal Parasitic Diseases Lab, USDA/ARS, Beltsville, MD 20705, USA.
| | - Dante Zarlenga
- Animal Parasitic Diseases Lab, USDA/ARS, Beltsville, MD 20705, USA
| | - Mariam Bakshi
- Animal Parasitic Diseases Lab, USDA/ARS, Beltsville, MD 20705, USA
| | - Bryan Vinyard
- Statistics Group, Northeast Area Office of the Director, USDA/ARS, Beltsville, MD 20705, USA
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Ostertagia ostertagi Mediates Early Host Immune Responses via Macrophage and Toll-Like Receptor Pathways. Infect Immun 2021; 89:IAI.00017-21. [PMID: 33685941 DOI: 10.1128/iai.00017-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/25/2021] [Indexed: 11/20/2022] Open
Abstract
Ostertagia ostertagi is an abomasal parasite with significant economic impact on the cattle industry. Early host immune responses are poorly understood. Here, we examined time course expression of Toll-like receptors (TLRs) in peripheral blood mononuclear cells (PBMC) during infection where PBMC macrophages (Mϕ) generated both pro- and anti-inflammatory responses when incubated with excretory/secretory products (ESP) from fourth-stage larvae (OoESP-L4) or adult worms (OoESP-Ad). First, changes in cell morphology clearly showed that both OoESP-L4 and OoESP-Ad activated PBMC-Mϕ in vitro, resulting in suppressed CD40 and increased CD80 expression. Expression of mRNAs for TLR1, -4, -5, and -7 peaked 7 days postinfection (dpi) (early L4), decreased by 19 dpi (postemergent L4 and adults) and then increased at 27 dpi (late adults). The proinflammatory cytokine tumor necrosis factor alpha (TNF-α) (transcript and protein) increased in the presence of OoESP-Ad, and the anti-inflammatory cytokine interleukin 10 (IL-10) (protein) decreased in the presence of OoESP-L4 or OoESP-Ad; however, IL-10 mRNA was upregulated, and IL-6 (protein) was downregulated by OoESP-L4. When PBMC-Mϕ were treated with ligands for TLR4 or TLR5 in combination with OoESP-Ad, the transcripts for TNF-α, IL-1, IL-6, and IL-10 were significantly downregulated relative to treatment with TLR4 and TLR5 ligands only. However, the effects of TLR2 ligand and OoESP-Ad were additive, but only at the lower concentration. We propose that O. ostertagi L4 and adult worms utilize competing strategies via TLRs and Mϕ to confuse the immune system, which allows the worm to evade the host innate responses.
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Characterization of IL-10-producing neutrophils in cattle infected with Ostertagia ostertagi. Sci Rep 2019; 9:20292. [PMID: 31889109 PMCID: PMC6937330 DOI: 10.1038/s41598-019-56824-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 12/17/2019] [Indexed: 02/07/2023] Open
Abstract
IL-10 is a master regulator of immune responses, but its cellular source and function in cattle during the initial phase of immune priming have not been well established. Despite a massive B cell response in the abomasal draining lymph nodes in Ostertagia ostertagi (OO)-infected cattle, protective immunity is slow to develop, and partial protection requires years of repeated exposure. In addressing this problem, our initial hypothesis was that B cells produce IL-10 that downregulates the host protective immune response. However, our results showed that neutrophils made up the majority of IL-10-producing cells in circulation and in secondary lymphoid tissues, particularly the spleen (80%). Conversely, IL-10-producing B cells were rare. In addition, approximately 10% to 20% of the neutrophils in the blood and spleen expressed MHC II and were IL-10 negative, suggesting that neutrophils could also participate in antigen presentation. In vitro investigation of bovine neutrophils revealed that exposure thereof to OO extract increased IL-10 and MHC II expression in these cells in a dose-dependent manner, consistent with IL-10+/MHC II+ neutrophils detected in cattle shortly after experimental OO infection. Co-culture of untreated neutrophils with anti-CD3 antibody (Ab)-stimulated CD4+ T cells led to enhanced T cell activation; also, IL-10 depletion with neutralizing Ab enhanced the stimulatory function of neutrophils. OO extract depressed neutrophil stimulation of CD4+ T cells in the presence of IL-10-neutralizing Ab, suggesting that OO utilizes both IL-10-dependent and independent mechanisms to manipulate the bovine immune response. Finally, contact and viability were required for T cell-stimulatory neutrophil function. This report, to the best of our knowledge, is the first to demonstrate that neutrophil-derived IL-10 is directly involved in T cell regulation in cattle. Our data suggest that neutrophils and neutrophil-derived IL-10 are co-opted by nematode parasites and other pathogens to attenuate host immune responses and facilitate pathogen survival.
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The role of antibody in parasitic helminth infections. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 828:1-26. [PMID: 25253025 DOI: 10.1007/978-1-4939-1489-0_1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Granule exocytosis of granulysin and granzyme B as a potential key mechanism in vaccine-induced immunity in cattle against the nematode Ostertagia ostertagi. Infect Immun 2013; 81:1798-809. [PMID: 23478322 DOI: 10.1128/iai.01298-12] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Ostertagia ostertagi is considered one of the most economically important bovine parasites. As an alternative to anthelmintic treatment, an experimental host-protective vaccine was previously developed on the basis of ASP proteins derived from adult worms. Intramuscular injection of this vaccine, combined with QuilA as an adjuvant, significantly reduced fecal egg counts by 59%. However, the immunological mechanisms triggered by the vaccine are still unclear. Therefore, in this study, the differences in immune responses at the site of infection, i.e., the abomasal mucosa, between ASP-QuilA-vaccinated animals and QuilA-vaccinated control animals were investigated on a transcriptomic level by using a whole-genome bovine microarray combined with histological analysis. Sixty-nine genes were significantly impacted in animals protected by the vaccine, 48 of which were upregulated. A correlation study between the parasitological parameters and gene transcription levels showed that the transcription levels of two of the upregulated genes, those for granulysin (GNLY) and granzyme B (GZMB), were negatively correlated with cumulative fecal egg counts and total worm counts, respectively. Both genes were also positively correlated with each other and with another upregulated gene, that for the IgE receptor subunit (FCER1A). Surprisingly, these three genes were also correlated significantly with CMA1, which encodes a mast cell marker, and with counts of mast cells and cells previously described as globule leukocytes. Furthermore, immunohistochemical data showed that GNLY was present in the granules of globule leukocytes and that it was secreted in mucus. Overall, the results suggest a potential role for granule exocytosis by globule leukocytes, potentially IgE mediated, in vaccine-induced protection against O. ostertagi.
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RINALDI M, GELDHOF P. Immunologically based control strategies for ostertagiosis in cattle: where do we stand? Parasite Immunol 2012; 34:254-64. [DOI: 10.1111/j.1365-3024.2011.01313.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Mihi B, Rinaldi M, Geldhof P. Effect of an Ostertagia ostertagi infection on the transcriptional stability of housekeeping genes in the bovine abomasum. Vet Parasitol 2011; 181:354-9. [DOI: 10.1016/j.vetpar.2011.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 04/05/2011] [Accepted: 04/08/2011] [Indexed: 10/18/2022]
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Knight JS, Baird DB, Hein WR, Pernthaner A. The gastrointestinal nematode Trichostrongylus colubriformis down-regulates immune gene expression in migratory cells in afferent lymph. BMC Immunol 2010; 11:51. [PMID: 20950493 PMCID: PMC2970587 DOI: 10.1186/1471-2172-11-51] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 10/17/2010] [Indexed: 01/03/2023] Open
Abstract
Background Gastrointestinal nematode (GIN) infections are the predominant cause of economic losses in sheep. Infections are controlled almost exclusively by the use of anthelmintics which has lead to the selection of drug resistant nematode strains. An alternative control approach would be the induction of protective immunity to these parasites. This study exploits an ovine microarray biased towards immune genes, an artificially induced immunity model and the use of pseudo-afferent lymphatic cannulation to sample immune cells draining from the intestine, to investigate possible mechanisms involved in the development of immunity. Results During the development of immunity to, and a subsequent challenge infection with Trichostrongylus colubriformis, the transcript levels of 2603 genes of cells trafficking in afferent intestinal lymph were significantly modulated (P < 0.05). Of these, 188 genes were modulated more than 1.3-fold and involved in immune function. Overall, there was a clear trend for down-regulation of many genes involved in immune functions including antigen presentation, caveolar-mediated endocytosis and protein ubiquitination. The transcript levels of TNF receptor associated factor 5 (TRAF5), hemopexin (HPX), cysteine dioxygenase (CDO1), the major histocompatability complex Class II protein (HLA-DMA), interleukin-18 binding protein (IL-18BP), ephrin A1 (EFNA1) and selenoprotein S (SELS) were modulated to the greatest degree. Conclusions This report describes gene expression profiles of afferent lymph cells in sheep developing immunity to nematode infection. Results presented show a global down-regulation of the expression of immune genes which may be reflective of the natural temporal response to nematode infections in livestock.
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Affiliation(s)
- Jacqueline S Knight
- AgResearch Ltd., Hopkirk Research Institute, Grasslands Research Centre, Palmerston North 4442, New Zealand.
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Li RW, Hou Y, Li C, Gasbarre LC. Localized complement activation in the development of protective immunity against Ostertagia ostertagi infections in cattle. Vet Parasitol 2010; 174:247-56. [PMID: 20884121 DOI: 10.1016/j.vetpar.2010.08.037] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 07/27/2010] [Accepted: 08/24/2010] [Indexed: 12/18/2022]
Abstract
The abomasal nematode Ostertagia ostertagi is a major causal agent contributing to production inefficiencies in the cattle industry in temperate regions of the world. Protective immunity to infections develops very slowly and resistance to reinfection manifests only after prolonged exposure. Mechanisms underlying the development of protective immunity remain largely unexplored. Immune animals, which have significantly reduced worm burdens, were developed after multiple drug-attenuated experimental infections and were compared to a primary infected group and their respective uninfected controls. In this study, transcriptomic analysis identified three signaling pathways significantly impacted during both primary and repeat infections, the complement system, leukocyte extravasation and acute phase responses. Increased mRNA levels of complement components C3, factor B (CFB) and factor I (CFI) in the abomasal mucosa of the infected cattle were confirmed using quantitative PCR while Western blot analysis established the presence of elevated levels of activated C3 proteins in the mucosa. One of the initiators of local complement activation could be related to secretory IgA and IgM because infections significantly up-regulated expression of J chain (IGJ), as well as polymeric Ig receptor (PIGR) and an IgM-specific receptor (FAIM3), suggesting sustained increases in both synthesis and transepithelial transport of IgA and IgM during the infection. The elevated levels of pro-inflammatory cytokines, such as IL-4 and IL-1β, during infection may be involved in gene regulation of complement components. Our results suggest enhanced tissue repair and mucin secretion in immune animals may also contribute to protective immunity. These results are the first evidence that local complement activation may be involved in the development of long-term protective immunity and provide a novel mechanistic insight into resistance against O. ostertagi in cattle.
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Affiliation(s)
- Robert W Li
- Bovine Functional Genomics Laboratory, Animal and Natural Resources Institute, United States Department of Agriculture, Beltsville, MD 20705, USA.
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Zarlenga DS, Gasbarre LC. From parasite genomes to one healthy world: Are we having fun yet? Vet Parasitol 2009; 163:235-49. [PMID: 19560277 DOI: 10.1016/j.vetpar.2009.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
In 1990, the Human Genome Sequencing Project was established. This laid the ground work for an explosion of sequence data that has since followed. As a result of this effort, the first complete genome of an animal, Caenorhabditis elegans was published in 1998. The sequence of Drosophila melanogaster was made available in March, 2000 and in the following year, working drafts of the human genome were generated with the completed sequence (92%) being released in 2003. Recent advancements and next-generation technologies have made sequencing common place and have infiltrated every aspect of biological research, including parasitology. To date, sequencing of 32 apicomplexa and 24 nematode genomes are either in progress or near completion, and over 600k nematode EST and 200k apicomplexa EST submissions fill the databases. However, the winds have shifted and efforts are now refocusing on how best to store, mine and apply these data to problem solving. Herein we tend not to summarize existing X-omics datasets or present new technological advances that promise future benefits. Rather, the information to follow condenses up-to-date-applications of existing technologies to problem solving as it relates to parasite research. Advancements in non-parasite systems are also presented with the proviso that applications to parasite research are in the making.
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Affiliation(s)
- Dante S Zarlenga
- USDA, ARS, ANRI Animal Parasitic Diseases Laboratory, Beltsville, MD 20705, USA.
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Araujo RN, Padilha T, Zarlenga D, Sonstegard T, Connor EE, Van Tassel C, Lima WS, Nascimento E, Gasbarre LC. Use of a candidate gene array to delineate gene expression patterns in cattle selected for resistance or susceptibility to intestinal nematodes. Vet Parasitol 2008; 162:106-15. [PMID: 19375862 DOI: 10.1016/j.vetpar.2008.12.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 12/12/2008] [Accepted: 12/15/2008] [Indexed: 12/12/2022]
Abstract
In the present study, we use microarray technology to investigate the expression patterns of 381 genes with known association to host immune responses. Hybridization targets were derived from previously characterized bovine cDNAs. A total of 576 reporters (473 sequence-validated cDNAs and 77 controls) were spotted onto glass slides in two sets of four replicates. Two color, comparative hybridizations across both mesenteric lymph node (MLN) and small intestine mucosa (SIM) RNA samples were done between animals with previously demonstrated phenotypic differences based on natural exposure to gastrointestinal (GI) nematodes over a 6-month exposure period. A total of 138 significant hybridization differences were detected by mixed model analysis of variance. A subset of these significant differences was validated by quantitative, real-time RT-PCR to assay transcript levels for 18 genes. These results confirmed that in the SIM, susceptible animals showed significantly higher levels in the genes encoding IGHG1, CD3E, ACTB, IRF1, CCL5 and C3, while in the MLN of resistant animals, higher levels of expression were confirmed for PTPRC, CD1D and ITGA4. Combined, the results indicate that immune responses against GI nematode infections involve multiple response pathways. Higher levels of expression for IgE receptor, integrins, complement, monocyte/macrophage and tissue factors are related to resistance. In contrast, higher levels of expression for immunoglobulin chains and TCRs are related to susceptibility. Identification of these genes provides a framework to better understand the genetic variation underlying parasite resistance.
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Affiliation(s)
- Ricardo N Araujo
- USDA, ARS, Bovine Functional Genomics Laboratory, Beltsville, MD, USA
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Abstract
Gastrointestinal nematode parasitism is arguably the most serious constraint affecting sheep production worldwide. Economic losses are caused by decreased production, the costs of prophylaxis and treatment, and the death of the infected animals. The nematode of particular concern is Haemonchus contortus, which can cause severe blood loss resulting in anemia, anorexia, depression, loss of condition, and eventual death. The control of nematode parasites traditionally relies on anthelmintic treatment. The evolution of anthelmintic resistance in nematode populations threatens the success of drug treatment programs. Alternative strategies for control of nematode infections are being developed, and one approach is to take advantage of the host's natural or acquired immune responses, which can be used in selection programs to increase the level of resistance in the population. Vaccination can also be used to stimulate or boost the host's acquired immunity. The induction of protective resistance is dependent on the pattern of cytokine gene expression induced during infection by two defined CD4+ T-helper cell subsets, which have been designated as Th1 or Th2. Intracellular parasites most often invoke a Th1-type response, and helminth parasites a Th2-type response. Breeds of sheep resistant to infection have developed resistance over a much longer term of host-parasite relationship than genetically selected resistant lines. The immune components involved in these different responses and types of host-parasite relationships will be reviewed. The potential for using vaccines has been investigated, with variable results, for several decades. The few successes and potential new antigen candidates will also be reviewed.
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Affiliation(s)
- J E Miller
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, 70803, USA.
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Li RW, Sonstegard TS, Van Tassell CP, Gasbarre LC. Local inflammation as a possible mechanism of resistance to gastrointestinal nematodes in Angus heifers. Vet Parasitol 2007; 145:100-7. [PMID: 17182188 DOI: 10.1016/j.vetpar.2006.11.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Revised: 11/17/2006] [Accepted: 11/21/2006] [Indexed: 12/31/2022]
Abstract
Understanding mechanisms of resistance to gastrointestinal nematodes is important in developing effective and sustainable control programs. A resource population of Angus cattle consisting of approximately 600 animals with complete pedigree records has been developed. The majority of these animals were completely characterized for their resistance to natural challenge by gastrointestinal nematodes. As the first step towards understanding the molecular basis of disease resistance, we investigated expression profiles of 17 cytokines, cytokine receptors, and chemokines using real-time RT-PCR in animals demonstrating resistance or susceptibility to pasture challenge. The animals exposed to natural infection for approximately 6 months were treated to remove existing parasites and then experimentally challenged with both Ostertagia ostertagi and Cooperia oncophora. The mRNA expression profiles of these genes in abomasal and mesenteric lymph nodes (ALN, MLN), fundic and pyloric abomasa (FA, PA), and small intestine (SI) were compared between resistant and susceptible animals. Resistant heifers exhibited elevated expression of inflammatory cytokines such as TNFalpha, IL-1beta, and MIP-1alpha in fundic and pyloric abomasa 7 days post infection. Expression levels of IL-10, polymeric immunoglobullin receptor gene (PIGR), and WSX-1 were also 2.7-19.9-folds higher in resistant than susceptible heifers in these tissues. No difference in expression of CXCL6, CXCL10, IFN-gamma, IL-2, IL-4, IL-6, IL-8, IL-12 p40, IL-13, IL-15 and IL-18 was observed between the two groups. The expression of MIP-1alpha, IL-6, and IL-10 was also elevated in small intestines in resistant animals. In contrast, little difference in expression of these genes was detected between resistant and susceptible groups in the draining lymph nodes. These data indicate that resistant animals can better maintain inflammatory responses at the site of infection, suggesting a possible novel mechanism of resistance.
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Affiliation(s)
- Robert W Li
- Bovine Functional Genomics Laboratory, USDA-ARS, Beltsville, MD 20705, USA.
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Stromberg BE, Gasbarre LC. Gastrointestinal Nematode Control Programs with an Emphasis on Cattle. Vet Clin North Am Food Anim Pract 2006; 22:543-65. [PMID: 17071352 DOI: 10.1016/j.cvfa.2006.08.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Control strategies for nematode parasites rely on knowledge of the relationships between the parasites and their hosts. Specifically, these programs are based on identifying crucial points of interaction in the environment provided by the host, including genetics and the immune response, and critical periods in the physical environment in which the eggs and larval stages must develop. When these targets are identified and the interactions understood, cost-effective sustainable programs can be developed using currently available antiparasitic compounds. Resistance to the major classes of anthelmintic compounds requires consideration of new approaches, such as immunity or genetics of the host. Additionally, the efficacy of these compounds can be expanded with combined or concomitant use. Increased study of the use of novel approaches, including fungi, elements such as copper, and plant products, has also occurred. This article explores each of these areas to allow readers to appreciate how various approaches may be developed and incorporated into an effective parasite control program.
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Affiliation(s)
- Bert E Stromberg
- Veterinary and Biomedical Sciences Department, College of Veterinary Medicine, University of Minnesota, 1971 Commonwealth Avenue, St. Paul, MN 55108, USA.
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Claerebout E, Vercauteren I, Geldhof P, Olbrechts A, Zarlenga DS, Goddeeris BM, Vercruysse J. Cytokine responses in immunized and non-immunized calves after Ostertagia ostertagi infection. Parasite Immunol 2005; 27:325-31. [PMID: 16149990 DOI: 10.1111/j.1365-3024.2005.00780.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The objective of this study was to evaluate abomasal cytokine responses in helminth-naive calves and calves vaccinated with protective antigen fractions from Ostertagia ostertagi after an experimental challenge infection with infective third stage (L3) larvae. Abomasal lymph nodes and/or abomasal mucosa were collected and messenger RNA for the Th1 cytokines (IFN-gamma, IL-2, IL-12 p40 subunit), the Th2 cytokines (IL-4, IL-5, IL-6, IL-10, IL-13, IL-15) and the Th3/Tr cytokine TGF-beta was quantified by real-time RT-PCR. Vaccination had no effect on cytokine profiles in either the abomasal lymph nodes or the abomasal mucosa. However, following infection all calves showed a significant decrease in the Th1 cytokines, IFN-gamma and IL-12 p40, and a significant increase in the Th2 cytokines, IL-4, IL-5, IL-10 and IL-13 in the lymph nodes, compared to non-infected calves. No correlation between the Th2 response and protection induced by vaccination could be demonstrated. In contrast, a Th2 pattern was not observed in the mucosa of the infected calves, which exhibited an increase in IFN-gamma as well as in the Th2 cytokines IL-4, IL-5 and IL-10 mRNA. No significant association was observed in the abomasal mucosa between any examined cytokine mRNA level and immune effector responses such as parasite-specific antibodies or the number of mucosal mast cells or eosinophils.
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Affiliation(s)
- E Claerebout
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
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17
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Gómez-Muñoz MT, Canals-Caballero A, Almeria S, Pasquali P, Zarlenga DS, Gasbarre LC. Inhibition of bovine T lymphocyte responses by extracts of the stomach worm Ostertagia ostertagi. Vet Parasitol 2004; 120:199-214. [PMID: 15041095 DOI: 10.1016/j.vetpar.2004.01.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2003] [Accepted: 01/14/2004] [Indexed: 11/17/2022]
Abstract
Lowered immune responses during bovine ostertagiosis have been reported in both in vivo and in vitro assay systems. In the present study we have employed three different life cycle stages of the nematode Ostertagia ostertagi to determine if products of this economically important parasite inhibit in vitro proliferation of Con A-stimulated cells from uninfected animals. We have demonstrated an inhibitory effect upon the growth of Con A-stimulated lymphocytes after addition of fourth stage larval (L4) soluble extract (L4SE) to the cultures. In contrast, extracts from the third stage larvae (L3) had little or no inhibitory activity. The suppressive products were also shown to be secreted by the late L4. The suppressive activity is reversible if the L4 products are removed from culture. There is no immediate effect on proliferating cells and the L4SE must be in culture for 24-48 h before suppression is observable. The L4SE caused slight but not statistically significant decreases in the percentage of T cells and increases in B cell percentages in cultures when compared with cultures stimulated with Con A alone. No changes were seen in percentage of cells positive for markers for CD4, CD8, gammadelta T cells, or monocytes/macrophages as a consequence of the addition of L4SE. In contrast, there was a strong and significant reduction in the expression of the IL-2 receptors in cells cultured in the presence of the worm extract. There was no evidence of either necrosis or apoptosis resulting from the presence of L4 products in culture. The expression of messenger RNA for interleukin-2, -4, -13, tumor necrosis factor-alpha (TNF-alpha), and gamma-interferon (gamma-IFN) was decreased when L4SE was included in cultures of Con A-stimulated cells compared to cultures stimulated with Con A only. In contrast, messenger RNA expression of transforming growth factor-beta (TGF-beta) and interleukin-10 (IL-10) was increased in cells growing in the presence of L4 products. The potential role of these cytokines during ostertagiosis is discussed.
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Affiliation(s)
- M T Gómez-Muñoz
- Departamento de Atención Sanitaria, Salud Pública y Sanidad Animal, Facultad de Ciencias Experimentales y de la Salud, Universidad Cardenal Herrera-CEU, Valencia, Spain.
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18
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Balic A, Bowles VM, Liu YS, Meeusen ENT. Local immune responses in sensitized sheep following challenge infection with Teladorsagia circumcincta. Parasite Immunol 2004; 25:375-81. [PMID: 14521580 DOI: 10.1046/j.1365-3024.2003.00646.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sheep were sensitized by weekly infections with Teladorsagia circumcincta over a 9-week period. After a 12-week rest, sheep were divided into four groups and killed without challenge or 3, 5 and 10 days post challenge (DPC) with 50000 L3. Recovery of challenge larvae from abomasal scrapings was highest at 3 DPC while no parasites were recovered by 10 DPC. Abomasal lymph nodes (ALN) of challenged sheep were significantly larger at 5 DPC, coinciding with an increase in the proportion of CD4 T cells and a decrease in CD21+ cells, probably reflecting the loss of CD21 from terminally differentiated antibody secreting cells. A significant increase was observed in gammadelta-TCR+ cells at 3 DPC in the ALN, while their number slightly decreased in the abomasal tissues throughout the challenge period. The number of tissue eosinophils was dramatically increased after challenge compared with the unchallenged controls, with a peak at 3 DPC, coinciding with the peak in larval recovery. CD4+ cells significantly increased in the abomasal tissues at 5 DPC, while no changes in globule leucocytes were observed until 10 DPC. Antibody-secreting cell probes (ASC-probes) generated from the ALN showed highest reactivity against larval antigens at 5 DPC. This reactivity was predominantly directed against regions between 90 and 100 kDa and 30-35 kDa in the L3 preparation and lower molecular weight antigens in the L4. No reactivity was observed against the adult extract. The 30-35 kDa antigen seemed to exist as a high molecular weight complex in L3 homogenate and was not susceptible to protease K treatment, suggesting it may be non-protein in nature.
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Affiliation(s)
- A Balic
- Centre for Animal Biotechnology, School of Veterinary Science, The University of Melbourne, Victoria, Australia
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19
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Abstract
Immunological memory responses to intracellular protozoa and extracellular helminths govern host resistance and susceptibility to reinfection. Humans and livestock living in parasitic disease endemic regions face continuous exposure from a very early age that often leads to asymptomatic chronic infection over their entire lifespan. Fundamental immunological studies suggest that the generation of T-cell memory is driven by tightly coordinated innate and adaptive cellular immune responses rapidly triggered following initial host infection. A key distinguishing feature of immune memory maintenance between the majority of parasitic diseases and most bacterial or viral diseases is long-term antigen persistence. Consequently, functional parasite immune memory is in a continuous, dynamic flux between activation and deactivation producing functional parasite killing or functional memory cell death. In this sense, T-cell immune memory can be regarded as "memory illusion." Furthermore, due to the finite capacity of memory lymphocytes to proliferate, continuous parasite antigen stimulation may exceed a threshold level at some point in the chronically infected host. This may result in suboptimal effector immune memory leading to host susceptibility to reinfection, or immune dysregulation yielding disease reactivation or immune pathology. The goal of this review is to highlight, through numerous examples, what is currently known about T-cell immune memory to parasites and to provide compelling hypotheses on the survival and maintenance of parasite "memory illusion." These novel concepts are discussed in the context of rationale parasite vaccine design strategies.
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Affiliation(s)
- David A Brake
- Veterinary Medicine Biologicals Development, Pfizer Animal Health Group, Pfizer, Inc., Groton, Connecticut 06340, USA.
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20
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Abstract
The natural genetic variability of the ruminant immune system provides a feasible means to control gastrointestinal (GI) parasite infection without anthelmintics. However, the paradigm of traditional selection has not been effectively applied to the moderately heritable traits of parasite resistance (h approximately equal to 0.3) due to the difficulty and expense of gathering accurate phenotypes in a commercial production setting. These characteristics make host traits related to GI nematode infection ideal candidates for genomics-based research. To initiate explanation of important allelic differences, economic trait loci (ETL) are being identified and mapped using a resource population of Angus cattle segregating for GI nematode resistance and susceptibility to the two most common nematode parasites of US cattle, Ostertagia ostertagi and Cooperia oncophora. The population is composed of five generations of half-sib progeny with complete phenotypic records produced from controlled infections. To detect the genomic locations of the three distinct phenotypic traits being expressed (innately immune, acquired immune, and immunologically non-responsive), genotypes have been generated for DNA markers (N=199) spaced at regular intervals (approximately 20cm intervals) throughout the entire genome (3000cm). Although initial ETL detection may be limited by half-sib family size, the unique structure of this population provides additional statistical power for refining map position of potential ETL. After allele frequency and contribution to phenotype are determined in this population, marker tests associated with ETL most beneficial for controlling parasite infection can be accurately used for selection. Comparative map and functional genomic information from humans and other species of biomedical importance will be utilized in further investigations to elucidate the genes underlying ETL.
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Affiliation(s)
- T S Sonstegard
- Gene Evaluation and Mapping Laboratory, Animal and Natural Resources Institute, USDA-ARS Beltsville Area, Building 200, Room 2A, BARC-East, Beltsville, MD 20705-1350, USA
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21
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Gasbarre LC, Leighton EA, Sonstegard T. Role of the bovine immune system and genome in resistance to gastrointestinal nematodes. Vet Parasitol 2001; 98:51-64. [PMID: 11516579 DOI: 10.1016/s0304-4017(01)00423-x] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gastrointestinal nematode infections of cattle remain a constraint on the efficient raising of cattle on pasture throughout the world. Most of the common genera of parasites found in cattle stimulate an effective level of protective immunity in most animals within the herd after the animals have been on pasture for several months. In contrast, cattle remain susceptible to infection by Ostertagia for many months, and immunity that actually reduces the development of newly acquired larvae is usually not evident until the animals are more than 2 years old. This prolonged susceptibility to reinfection is a major reason that this parasite remains the most economically important GI nematode in temperate regions of the world. Although, animals remain susceptible to reinfection for a prolonged period of time, there are a number of manifestations of the immune response that result in an enhanced level of herd immunity. These include a delay in the development time of the parasites, an increase in the number of larvae that undergo an inhibition in development, morphological changes in the worms, stunting of newly acquired worms, and most importantly a reduction in the number of eggs produced by the female worms. The overall result of these manifestations of immunity is a reduction in parasite transmission within the cattle herd. The immune mechanisms responsible for these different types of functional immunity remain to be defined. In general, GI nematode infections in mammals elicit very strong Th2-like responses characterized by high levels of Interleukin 4 (IL4), high levels of IgG1 and IgE antibodies, and large numbers of mast cells. In cattle, the most extensively studied GI nematode, in regards to host immune responses, is Ostertagia ostertagi. In Ostertagia infections, antigens are presented to the host in the draining lymph nodes very soon after infection, and within the first 3-4 days of infection these cells have left the nodes, entered the peripheral circulation, and have homed to tissues immediately surrounding the parasite where they become established. The immune response seen in the abomasum is in many ways are similar to that seen other mammalian hosts, with high levels of expression of IL4 in the draining lymph nodes and in lymphocytes isolated from the mucosa. But unlike a number of other systems, lymphocyte populations taken from Ostertagia infected cattle seem to be up-regulated for a number of other cytokines, most notably Interferon (IFN, implying that in Ostertagia infections, the immune response elicit is not simply a stereotypic Th2 response. In addition, effector cell populations in the tissues surrounding the parasites, are not typical, inferring the Ostertagia has evolved means to suppress or evade protective immune mechanisms. Studies have also demonstrated that the number of nematode eggs/gram (EPG) in feces of pastured cattle is strongly influenced by host genetics and that the heritability of this trait is approximately 0.30. In addition, EPG values are not "normally" distributed and a small percentage of a herd is responsible for the majority of parasite transmission. This suggests that genetic management of a small percentage of the herd can considerably reduce overall parasite transmission. A selective breeding program has been initiated to identify the host genes controlling resistance/susceptibility to the parasites. The best indicator of the number of Cooperia infecting a host is the EPG value, while Ostertagia is best measured by serum pepsinogen levels, weight gain, and measures of anemia. Other phenotypic measures are either not significantly associated with parasite numbers or are very weakly correlated. In addition, calves can be separated into three types: (1) Type I which never demonstrates high EPG values, (2) Type II which shows rises in EPG values through the first 2 months on pasture which then fall and remain at levels associated with Type I calves, and (3) Type III calves which maintain high EPG levels. The approximate percentage of these calves is 25:50:25 respectively. Because these cattle are segregating for traits involved in resistance and susceptibility to GI nematodes, this resource population is being used to effectively detect the genomic locations of these Economic Trait Loci (ETL). For relational analysis between phenotype and genome location, over 80,000 genotypes have been generated by PCR amplification, and marker genotypes have been scored to produce inheritance data. The marker allele inheritance data is currently being statistically analyzed to detect patterns of co-segregation between allele haplotype and EPG phenotypes. Statistical power of this genome-wide scan has been strengthened by including genotypic data from the historic pedigree. In our herd, paternal half-sib families range from 5-13 progeny/sire, and extensive marker genotypes are available from ancestors of the population most of which are paternally descended from a single founding sire. Once ETL have been identified the next will be to refine ETL map resolution in attempt to discover the genes underlying disease phenotypes. Accurate identification of genes controlling resistance will offer the producer several alternatives for disease control. For a non-organic producer, the small percentage of susceptible animals can be targeted for drug administration. This approach would reduce both the cost of anthelmintics used and the odds for selection of drug resistant mutants, because the selective agent (drug) would not be applied over the entire parasite population. A second treatment option would be based on correcting a heritable immunologic condition. In this case, susceptible animals could be the targets for immunotherapy involving vaccines of immunomodulation. A final option would be genetic selection to remove susceptible animals from the herd. Producers with a high degree of risk for parasite-induced production losses, such as organic producers of producers in geographic areas with environmental conditions favorable to high rates of transmission would benefit the most from this strategy. In contrast, producers at low risk could take a more conservative approach and select against susceptibility when other factors were equal.
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Affiliation(s)
- L C Gasbarre
- Immunology and Disease Resistance Laboratory, ARS, USDA, Beltsville, MD 20705-5130, USA
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22
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Balic A, Bowles VM, Meeusen EN. The immunobiology of gastrointestinal nematode infections in ruminants. ADVANCES IN PARASITOLOGY 2000; 45:181-241. [PMID: 10751941 DOI: 10.1016/s0065-308x(00)45005-0] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The major gastrointestinal nematode parasites of ruminants all belong to the Order Strongylida and the family Trichostrongyloidea. Despite this close evolutionary relationship, distinct differences exist in the microenvironmental niches occupied by the developmental stages of the various parasites, which may account for the variable susceptibility of the different parasite species to the immune effector mechanisms generated by the host. In addition, different manifestations of resistance have been observed against the adult and larval stages of the same parasite species, and even against the same parasite stage. In particular, both rapid and delayed rejection of infective larval stages of gastrointestinal nematode parasites has been documented. This review will give an overview of the various manifestations of resistance to gastrointestinal nematode parasites of ruminants, as well as the immune mechanisms and antigens associated with the generation of immunity by the ruminant hosts to these parasites. In addition, a working model is provided aimed at reconciling most of the present knowledge on the different immune responses generated during infection with the various parasite rejection profiles. Extrapolation of these results to field conditions will need to take into account the variability imposed by seasonal changes and management practices, as well as the individual variability in immune responsiveness present in outbred animal populations.
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Affiliation(s)
- A Balic
- Centre for Animal Biotechnology, School of Veterinary Science, University of Melbourne, Victoria, Australia
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