1
|
Zheng Y, Young ND, Song J, Gasser RB. Genome-Wide Analysis of Haemonchus contortus Proteases and Protease Inhibitors Using Advanced Informatics Provides Insights into Parasite Biology and Host-Parasite Interactions. Int J Mol Sci 2023; 24:12320. [PMID: 37569696 PMCID: PMC10418638 DOI: 10.3390/ijms241512320] [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: 06/20/2023] [Revised: 07/24/2023] [Accepted: 07/24/2023] [Indexed: 08/13/2023] Open
Abstract
Biodiversity within the animal kingdom is associated with extensive molecular diversity. The expansion of genomic, transcriptomic and proteomic data sets for invertebrate groups and species with unique biological traits necessitates reliable in silico tools for the accurate identification and annotation of molecules and molecular groups. However, conventional tools are inadequate for lesser-known organismal groups, such as eukaryotic pathogens (parasites), so that improved approaches are urgently needed. Here, we established a combined sequence- and structure-based workflow system to harness well-curated publicly available data sets and resources to identify, classify and annotate proteases and protease inhibitors of a highly pathogenic parasitic roundworm (nematode) of global relevance, called Haemonchus contortus (barber's pole worm). This workflow performed markedly better than conventional, sequence-based classification and annotation alone and allowed the first genome-wide characterisation of protease and protease inhibitor genes and gene products in this worm. In total, we identified 790 genes encoding 860 proteases and protease inhibitors representing 83 gene families. The proteins inferred included 280 metallo-, 145 cysteine, 142 serine, 121 aspartic and 81 "mixed" proteases as well as 91 protease inhibitors, all of which had marked physicochemical diversity and inferred involvements in >400 biological processes or pathways. A detailed investigation revealed a remarkable expansion of some protease or inhibitor gene families, which are likely linked to parasitism (e.g., host-parasite interactions, immunomodulation and blood-feeding) and exhibit stage- or sex-specific transcription profiles. This investigation provides a solid foundation for detailed explorations of the structures and functions of proteases and protease inhibitors of H. contortus and related nematodes, and it could assist in the discovery of new drug or vaccine targets against infections or diseases.
Collapse
Affiliation(s)
- Yuanting Zheng
- Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, VIC 3010, Australia;
| | - Neil D. Young
- Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, VIC 3010, Australia;
| | - Jiangning Song
- Department of Data Science and AI, Faculty of IT, Monash University, Melbourne, VIC 3800, Australia;
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC 3800, Australia
- Monash Data Futures Institute, Monash University, Melbourne, VIC 3800, Australia
| | - Robin B. Gasser
- Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, VIC 3010, Australia;
| |
Collapse
|
2
|
Lubisch M, Moyzio S, Kaiser CS, Krafeld I, Leusder D, Scholz M, Hoepfner L, Hippler M, Liebau E, Kahl J. Using Caenorhabditis elegans to produce functional secretory proteins of parasitic nematodes. Acta Trop 2022; 225:106176. [PMID: 34627755 DOI: 10.1016/j.actatropica.2021.106176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/31/2021] [Accepted: 09/25/2021] [Indexed: 11/29/2022]
Abstract
The expression of antigens in their immunologically-active form remains a challenge, both in the analysis of regulatory pathways exploited by parasitic nematodes or in the development of vaccines. Despite the success of native proteins to induce protective immunity, recombinant proteins expressed in bacteria, yeast or insect cells offer only limited protective capacities, presumably due to incorrect folding or missing complex posttranslational modifications. The present study investigates the feasibility of using the free-living nematode Caenorhabditis elegans as an alternative expression system for proteins found in the secretome of parasitic nematodes. Exemplified by the expression of the extracellular superoxide dismutase from Haemonchus contortus (HcSODe) and the extracellular and glycosylated glutathione S-transferase from the filarial parasite Onchocerca volvulus (OvGST1), we continue our efforts to improve production and purification of recombinant proteins expressed in C. elegans. We demonstrate that sufficient quantities of functional proteins can be expressed in C. elegans for subsequent immunological and biochemical studies.
Collapse
Affiliation(s)
- Milena Lubisch
- Department of Molecular Physiology, Institute of Animal Physiology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Sven Moyzio
- Department of Molecular Physiology, Institute of Animal Physiology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Charlotte Sophia Kaiser
- Department of Molecular Physiology, Institute of Animal Physiology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Isabel Krafeld
- Department of Molecular Physiology, Institute of Animal Physiology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Dustin Leusder
- Department of Molecular Physiology, Institute of Animal Physiology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Martin Scholz
- Plant Biochemistry and Biotechnology, Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Lara Hoepfner
- Plant Biochemistry and Biotechnology, Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Michael Hippler
- Plant Biochemistry and Biotechnology, Institute of Plant Biology and Biotechnology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| | - Eva Liebau
- Department of Molecular Physiology, Institute of Animal Physiology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany.
| | - Janina Kahl
- Department of Molecular Physiology, Institute of Animal Physiology, Westfälische Wilhelms-University, Schlossplatz 8, 48143 Münster, Germany
| |
Collapse
|
3
|
Lu M, Tian X, Wang W, Zhang Y, Aimulajiang K, Tian AL, Li C, Yan R, Xu L, Song X, Li X. The excretory-secretory antigen HcADRM1 to generate protective immunity against Haemonchus contortus. Parasitology 2021; 148:1497-1508. [PMID: 34193327 PMCID: PMC11010155 DOI: 10.1017/s0031182021001141] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/02/2021] [Accepted: 06/23/2021] [Indexed: 11/06/2022]
Abstract
The prevention, treatment and control of Haemonchus contortus have been increasingly problematic due to its widespread occurrence and anthelmintic resistance. There are very few descriptions of recombinant antigens being protective for H. contortus, despite the success of various native antigen preparations, including Barbervax. We recently identified an H. contortus excretory–secretory antigen, H. contortus adhesion-regulating molecule 1 (HcADRM1), that served as an immunomodulator to impair host T-cell functions. Given the prophylactic potential of HcADRM1 protein as a vaccine candidate, we hereby assessed the efficacies of HcADRM1 preparations against H. contortus infection. Parasitological and immunological parameters were evaluated throughout all time points of the trials, including fecal egg counts (FEC), abomasal worm burdens, complete blood counts, cytokine production profiles and antibody responses. Active vaccination with recombinant HcADRM1 (rHcADRM1) protein induced protective immunity in inoculated goats, resulting in reductions of 48.9 and 58.6% in cumulative FEC and worm burdens. Simultaneously, passive administration of anti-HcADRM1 antibodies generated encouraging levels of protection with 46.7 and 56.2% reductions in cumulative FEC and worm burdens in challenged goats. In addition, HcADRM1 preparations-immunized goats showed significant differences in mucosal and serum antigen-specific immunoglobulin G (IgG) levels, total mucosal IgA levels, haemoglobin values and circulating interferon-γ, interleukin (IL)-4 and IL-17A production compared to control goats in both trials. The preliminary data of these laboratory trials validated the immunoprophylactic effects of rHcADRM1 protein. It can be pursued as a potential vaccine antigen to develop an effective recombinant subunit vaccine against H. contortus under field conditions.
Collapse
Affiliation(s)
- Mingmin Lu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Xiaowei Tian
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Wenjuan Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Yang Zhang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Kalibixiati Aimulajiang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Ai-Ling Tian
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province730046, P. R. China
| | - Charles Li
- U.S. Department of Agriculture, Animal Biosciences and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, Beltsville, MD20705, USA
| | - Ruofeng Yan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Lixin Xu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Xiaokai Song
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| | - Xiangrui Li
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, Jiangsu210095, P. R. China
| |
Collapse
|
4
|
Lu M, Tian X, Zhang Y, Wang W, Tian AL, Aimulajiang K, Liu L, Li C, Yan R, Xu L, Song X, Li X. Protection studies of an excretory-secretory protein HcABHD against Haemonchus contortus infection. Vet Res 2021; 52:3. [PMID: 33407892 PMCID: PMC7786147 DOI: 10.1186/s13567-020-00871-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 11/19/2020] [Indexed: 01/15/2023] Open
Abstract
Unlike the successful immunization of native H. contortus antigens that contributed to the realization of the first commercial vaccine Barbervax, not many studies revealed the encouraging protective efficacies of recombinant H. contortus antigens in laboratory trials or under field conditions. In our preliminary study, H. contortus α/β-hydrolase domain protein (HcABHD) was demonstrated to be an immunomodulatory excretory-secretory (ES) protein that interacts with goat T cells. We herein evaluated the protective capacities of two HcABHD preparations, recombinant HcABHD (rHcABHD) antigen and anti-rHcABHD IgG, against H. contortus challenge via active and passive immunization trials, respectively. Parasitological parameter, antibody responses, hematological pathology and cytokine profiling in unchallenged and challenged goats were monitored and determined throughout both trials. Subcutaneous administration of rHcABHD with Freund adjuvants elicited protective immune responses in challenged goats, diminishing cumulative fecal egg counts (FEC) and total worm burden by 54.0% and 74.2%, respectively, whereas passive immunization with anti-rHcABHD IgG conferred substantial protection to challenged goats by generating a 51.5% reduction of cumulative FEC and a 73.8% reduction of total worm burden. Additionally, comparable changes of mucosal IgA levels, circulating IgG levels, hemoglobin levels, and serum interleukin (IL)-4 and IL-17A levels were observed in rHcABHD protein/anti-rHcABHD IgG immunized goats in both trials. Taken together, the recombinant version of HcABHD might have further application under field conditions in protecting goats against H. contortus infection, and the integrated immunological pipeline of ES antigen identification, screening and characterization may provide new clues for further development of recombinant subunit vaccines to control H. contortus.
Collapse
Affiliation(s)
- Mingmin Lu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Xiaowei Tian
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Yang Zhang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Wenjuan Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Ai-Ling Tian
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, Gansu, P. R. China
| | - Kalibixiati Aimulajiang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Lianrui Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Charles Li
- Animal Biosciences and Biotechnology Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD, 20705, USA
| | - Ruofeng Yan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Lixin Xu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Xiaokai Song
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China
| | - Xiangrui Li
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, P. R. China.
| |
Collapse
|
5
|
Caffrey CR, Goupil L, Rebello KM, Dalton JP, Smith D. Cysteine proteases as digestive enzymes in parasitic helminths. PLoS Negl Trop Dis 2018; 12:e0005840. [PMID: 30138310 PMCID: PMC6107103 DOI: 10.1371/journal.pntd.0005840] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
We briefly review cysteine proteases (orthologs of mammalian cathepsins B, L, F, and C) that are expressed in flatworm and nematode parasites. Emphasis is placed on enzyme activities that have been functionally characterized, are associated with the parasite gut, and putatively contribute to degrading host proteins to absorbable nutrients [1–4]. Often, gut proteases are expressed as multigene families, as is the case with Fasciola [5] and Haemonchus [6], presumably expanding the range of substrates that can be degraded, not least during parasite migration through host tissues [5]. The application of the free-living planarian and Caenorhabditis elegans as investigative models for parasite cysteine proteases is discussed. Finally, because of their central nutritive contribution, targeting the component gut proteases with small-molecule chemical inhibitors and understanding their utility as vaccine candidates are active areas of research [7].
Collapse
Affiliation(s)
- Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
| | - Louise Goupil
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
- Department of Biology, University of San Francisco, San Francisco, California, United States of America
| | - Karina M. Rebello
- Laboratório de Toxinologia and Laboratório de Estudos Integrados em Protozoologia, Instituto Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - John P. Dalton
- School of Biological Sciences, Medical Biology Centre, Queen´s University Belfast, Belfast, United Kingdom
| | - David Smith
- School of Biological Sciences, Medical Biology Centre, Queen´s University Belfast, Belfast, United Kingdom
| |
Collapse
|
6
|
Matthews JB, Geldhof P, Tzelos T, Claerebout E. Progress in the development of subunit vaccines for gastrointestinal nematodes of ruminants. Parasite Immunol 2017; 38:744-753. [PMID: 27726158 DOI: 10.1111/pim.12391] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 10/05/2016] [Indexed: 11/30/2022]
Abstract
The global increase in anthelmintic resistant nematodes of ruminants, together with consumer concerns about chemicals in food, necessitates the development of alternative methods of control for these pathogens. Subunit recombinant vaccines are ideally placed to fill this gap. Indeed, they are probably the only valid option for the long-term control of ruminant parasitic nematodes given the increasing ubiquity of multidrug resistance in a range of worm species across the world. The development of a subunit multicellular parasite vaccine to the point of practical application would be a groundbreaking step in the control of these important endemic infections of livestock. This review summarizes the current status of subunit vaccine development for a number of important gastrointestinal nematodes of cattle and sheep, with a focus on the limitations and problems encountered thus far, and suggestions as to how these hurdles might be overcome.
Collapse
Affiliation(s)
- J B Matthews
- Vaccines Division, Moredun Research Institute, Pentlands Science Park, Edinburgh, UK
| | - P Geldhof
- Faculty of Veterinary Medicine, Department of Virology, Parasitology and Immunology, Ghent University, Merelbeke, Belgium
| | - T Tzelos
- Vaccines Division, Moredun Research Institute, Pentlands Science Park, Edinburgh, UK
| | - E Claerebout
- Faculty of Veterinary Medicine, Department of Virology, Parasitology and Immunology, Ghent University, Merelbeke, Belgium
| |
Collapse
|
7
|
Nascimento Santos L, Carvalho Pacheco LG, Silva Pinheiro C, Alcantara-Neves NM. Recombinant proteins of helminths with immunoregulatory properties and their possible therapeutic use. Acta Trop 2017; 166:202-211. [PMID: 27871775 DOI: 10.1016/j.actatropica.2016.11.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 11/13/2016] [Accepted: 11/15/2016] [Indexed: 02/06/2023]
Abstract
The inverse relationship between helminth infections and the development of immune-mediated diseases is a cornerstone of the hygiene hypothesis and studies were carried out to elucidate the mechanisms by which helminth-derived molecules can suppress immunological disorders. These studies have fostered the idea that parasitic worms may be used as a promising therapeutic alternative for prevention and treatment of immune-mediated diseases. We discuss the current approaches for identification of helminth proteins with potential immunoregulatory properties, including the strategies based on high-throughput technologies. We also explore the methodological approaches and expression systems used for production of the recombinant forms of more than 20 helminth immunomodulatory proteins, besides their performances when evaluated as immunotherapeutic molecules to treat different immune-mediated conditions, including asthma and inflammatory bowel diseases. Finally, we discuss the perspectives of using these parasite-derived recombinant molecules as tools for future immunotherapy and immunoprophylaxis of human inflammatory diseases.
Collapse
|
8
|
Abstract
Sheep are capable of developing protective immunity to Haemonchus contortus through repeated exposure to this parasite, although this immune protection is the result of a complex interaction among age, gender, physiological status, pregnancy, lactation, nutrition and innate and adaptive immunity in the host animal. There are multiple effectors of the protective immune response, which differ depending on the developmental stage of the parasite being targeted, and our understanding of the effector mechanisms has developed considerably in the 2000s. The rational design of vaccines based on 'natural' or 'exposed' antigens depends on an understanding of this exposure-induced immunity. However, the most effective current vaccines rely on protection via the induction of high circulating antibody levels to 'hidden' gut antigens of H. contortus. The success of this latter strategy has resulted in the launch of a vaccine, which is based on extracts of the parasite's gut, to aid in the control of Haemonchus in Australia. The development of recombinant subunit vaccines based on the components of the successful native vaccine has not yet been achieved and most of the recent successes with recombinant subunit vaccines have focussed on antigens unrelated to the gut antigens. The future integration of an understanding of the immunobiology of this parasite with advances in antigen identification, expression (or synthesis) and presentation is likely to be pivotal to the further development of these recombinant subunit vaccines. Recent progress in each of the components underpinning this integrated approach is summarized in this review.
Collapse
|
9
|
Yang Y, Ma Y, Chen X, Guo X, Yan B, Du A. Screening and analysis of Hc-ubq and Hc-gst related to desiccation survival of infective Haemonchus contortus larvae. Vet Parasitol 2015; 210:179-85. [DOI: 10.1016/j.vetpar.2015.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 03/18/2015] [Accepted: 03/22/2015] [Indexed: 01/18/2023]
|
10
|
Zhou QJ, Yang Y, Guo XL, Duan LJ, Chen XQ, Yan BL, Zhang HL, Du AF. Expression of Caenorhabditis elegans-expressed Trans-HPS, partial aminopeptidase H11 from Haemonchus contortus. Exp Parasitol 2014; 145:87-98. [PMID: 25128369 DOI: 10.1016/j.exppara.2014.08.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 06/29/2014] [Accepted: 08/04/2014] [Indexed: 01/26/2023]
Abstract
Aminopeptidase H11 present in the surface of intestine microvilli in Haemonchus contortus was identified as the most effective antigen candidate. However, its recombinant forms produced in Escherichiacoli, insect cells and yeast could not provide promising protection against H. contortus challenge, probably due to the inappropriate glycosylation and/or conformational folding. Herein, partial H11 containing the potential zinc-binding domain and two predicted glycosylation sites (nt 1 bp-1710 bp, Trans-HPS) was subcloned downstream of 5' flanking region of Caenorhabditis elegans cpr-1 gene in pPD95.77 vector, with the deletion of GFP gene. The recombinant was expressed in C. elegans and verified by blotting with anti-H11 and anti-Trans-HPS rabbit polyclonal antibodies and anti-His monoclonal antibody. Stably inherited Trans-HPS in worm descendants was achieved by integration using UV irradiation. Immunization with the crude Trans-HPS extracted from transgenic worms resulted in 37.71% reduction in faecal egg counts (FEC) (P<0.05) and 24.91% reduction in worm burden, but an upward curve with moderate rate of daily FEC in goats. These results suggested an apparent delay against H. contortus egg-laying in goats, which differed from that with bacteria-origin form of partial H11 (nt 670 bp-1710 bp, HPS) (26.04% reduction in FEC and 18.46% reduction in worm burden). These findings indicate the feasibility of sufficient C. elegans-expressed H11 for the immunological research and vaccine development.
Collapse
Affiliation(s)
- Qian-Jin Zhou
- School of Marine Science, Ningbo University, Ningbo 315211, China; Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Yi Yang
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Xiao-Lu Guo
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Li-Jun Duan
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Xue-Qiu Chen
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Bao-Long Yan
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Hong-Li Zhang
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China
| | - Ai-Fang Du
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
11
|
Roberts B, Antonopoulos A, Haslam SM, Dicker AJ, McNeilly TN, Johnston SL, Dell A, Knox DP, Britton C. Novel expression of Haemonchus contortus vaccine candidate aminopeptidase H11 using the free-living nematode Caenorhabditis elegans. Vet Res 2013; 44:111. [PMID: 24289031 PMCID: PMC4176091 DOI: 10.1186/1297-9716-44-111] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 11/19/2013] [Indexed: 11/28/2022] Open
Abstract
With the problem of parasitic nematode drug resistance increasing, vaccine development offers an alternative sustainable control approach. For some parasitic nematodes, native extracts enriched for specific proteins are highly protective. However, recombinant forms of these proteins have failed to replicate this protection. This is thought to be due to differences in glycosylation and/or conformation between native and recombinant proteins. We have exploited the free-living nematode Caenorhabditis elegans to examine its suitability as an alternative system for recombinant expression of parasitic nematode vaccine candidates. We focussed on Haemonchus contortus aminopeptidase H11 glycoprotein, which is enriched in a gut membrane fraction capable of inducing significant protection against this important ovine gastrointestinal nematode. We show that H. contortus H11 expressed in C. elegans is enzymatically active and MALDI mass spectrometry identifies similar di- and tri-fucosylated structures to those on native H11, with fucose at the 3- and/or 6-positions of the proximal GlcNAc. Some glycan structural differences were observed, such as lack of LDNF. Serum antibody to native H11 binds to C. elegans recombinant H11 and most of the antibody to rH11 or native H11 is directed to glycan moieties. Despite these similarities, no reduction in worm burden or faecal egg count was observed following immunisation of sheep with C. elegans-expressed recombinant H11 protein. The findings suggest that the di- and tri-fucosylated N-glycans expressed on rH11 do not contribute to the protective effect of H11 and that additional components present in native H11-enriched extract are likely required for enhancing the antibody response necessary for protection.
Collapse
Affiliation(s)
- Brett Roberts
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Ellis SE, Newlands GFJ, Nisbet AJ, Matthews JB. Phage-display library biopanning as a novel approach to identifying nematode vaccine antigens. Parasite Immunol 2012; 34:285-95. [PMID: 21770973 DOI: 10.1111/j.1365-3024.2011.01317.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Infections with parasitic nematodes are of significant welfare and economic importance worldwide, and because of the emergence of anthelmintic resistance, this has lead to alternative methods of parasite control being required. Vaccination offers a feasible alternative control, and the majority of research has focused on the production of recombinant versions of native antigens previously identified as protective in vaccinated animals. Attempts at the production of protective recombinant subunit vaccines have been hindered, however, as these antigens have invariably failed to replicate the same level of protective immune response as seen with the native versions. It has been proposed that these failures are owing to the fact that the recombinant proteins do not contain the appropriate post-translational modifications to retain the protective capacity of the native molecules. In this review, we discuss a novel approach to vaccine antigen identification through the application of random peptide phage-display libraries and their use to identify peptide sequences that potentially mimic the structure(s) of antigenic epitopes. This area of research is still relatively novel with respect to parasites, and the current state of the art will be discussed here.
Collapse
|
13
|
Assessment of cathepsin D and L-like proteinases of poultry red mite, Dermanyssus gallinae (De Geer), as potential vaccine antigens. Parasitology 2012; 139:755-65. [PMID: 22310226 DOI: 10.1017/s0031182011002356] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Vaccination is a feasible strategy for controlling the haematophagous poultry red mite Dermanyssus gallinae. A cDNA library enriched for genes upregulated after feeding was created to identify potential vaccine antigens. From this library, a gene (Dg-CatD-1) encoding a 383 amino acid protein (Dg-CatD-1) with homology to cathepsin D lysosomal aspartyl proteinases was identified as a potential vaccine candidate. A second gene (Dg-CatL-1) encoding a 341 amino acid protein (Dg-CatL-1) with homology to cathepsin L cysteine proteinases was also selected for further study. IgY obtained from naturally infested hens failed to detect Dg-CatD-1 suggesting that it is a concealed antigen. Conversely, Dg-CatL-1 was detected by IgY derived from natural-infestation, indicating that infested hens are exposed to Dg-CatL-1. Mortality rates 120 h after mites had been fed anti-Dg-CatD-1 were significantly higher than those fed control IgY (PF<0·01). In a survival analysis, fitting a proportional hazards model to the time of death of mites, anti-Dg-CatD-1 and anti-Dg-CatL-1 IgY had 4·42 and 2·13 times higher risks of dying compared with controls (PF<0·05). Dg-CatD-1 and L-1 both have potential as vaccine antigens as part of a multi-component vaccine and have the potential to be improved as vaccine antigens using alternative expression systems.
Collapse
|
14
|
Cantacessi C, Gasser RB. SCP/TAPS proteins in helminths--where to from now? Mol Cell Probes 2011; 26:54-9. [PMID: 22005034 DOI: 10.1016/j.mcp.2011.10.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 10/03/2011] [Accepted: 10/03/2011] [Indexed: 10/16/2022]
Abstract
A diverse array of proteins belonging to the SCP/TAPS 'family' has been described for various eukaryotic organisms, including parasites. Although SCP/TAPS proteins have been hypothesized to play key roles in various fundamental biological processes, such as host-pathogen interactions and defence mechanisms, there is still a limited understanding of the precise roles of these proteins. Here, we review current knowledge of key SCP/TAPS proteins of helminths and their proposed roles in parasite-host interactions. Molecular investigations of these molecules in parasites and the integration of structural and functional data could lead to new and innovative approaches for the treatment and control of parasitic diseases, with important biotechnological outcomes.
Collapse
Affiliation(s)
- Cinzia Cantacessi
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | | |
Collapse
|
15
|
Identification and characterization of the immunogenic cytotoxic TvCP39 proteinase gene of Trichomonas vaginalis. Int J Biochem Cell Biol 2011; 43:1500-11. [DOI: 10.1016/j.biocel.2011.07.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 06/17/2011] [Accepted: 07/05/2011] [Indexed: 12/31/2022]
|
16
|
Hulme SE, Whitesides GM. Die Chemie und der Wurm: Caenorhabditis elegans als Plattform für das Zusammenführen von chemischer und biologischer Forschung. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201005461] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
17
|
Hulme SE, Whitesides GM. Chemistry and the Worm: Caenorhabditis elegans as a Platform for Integrating Chemical and Biological Research. Angew Chem Int Ed Engl 2011; 50:4774-807. [DOI: 10.1002/anie.201005461] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Indexed: 12/15/2022]
|
18
|
SLO-1-channels of parasitic nematodes reconstitute locomotor behaviour and emodepside sensitivity in Caenorhabditis elegans slo-1 loss of function mutants. PLoS Pathog 2011; 7:e1001330. [PMID: 21490955 PMCID: PMC3072372 DOI: 10.1371/journal.ppat.1001330] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Accepted: 03/04/2011] [Indexed: 11/24/2022] Open
Abstract
The calcium-gated potassium channel SLO-1 in Caenorhabditis elegans was recently identified as key component for action of emodepside, a new anthelmintic drug with broad spectrum activity. In this study we identified orthologues of slo-1 in Ancylostoma caninum, Cooperia oncophora, and Haemonchus contortus, all important parasitic nematodes in veterinary medicine. Furthermore, functional analyses of these slo-1 orthologues were performed using heterologous expression in C. elegans. We expressed A. caninum and C. oncophora slo-1 in the emodepside-resistant genetic background of the slo-1 loss-of-function mutant NM1968 slo-1(js379). Transformants expressing A. caninum slo-1 from C. elegans slo-1 promoter were highly susceptible (compared to the fully emodepside-resistant slo-1(js379)) and showed no significant difference in their emodepside susceptibility compared to wild-type C. elegans (p = 0.831). Therefore, the SLO-1 channels of A. caninum and C. elegans appear to be completely functionally interchangeable in terms of emodepside sensitivity. Furthermore, we tested the ability of the 5′ flanking regions of A. caninum and C. oncophora slo-1 to drive expression of SLO-1 in C. elegans and confirmed functionality of the putative promoters in this heterologous system. For all transgenic lines tested, expression of either native C. elegans slo-1 or the parasite-derived orthologue rescued emodepside sensitivity in slo-1(js379) and the locomotor phenotype of increased reversal frequency confirming the reconstitution of SLO-1 function in the locomotor circuits. A potent mammalian SLO-1 channel inhibitor, penitrem A, showed emodepside antagonising effects in A. caninum and C. elegans. The study combined the investigation of new anthelmintic targets from parasitic nematodes and experimental use of the respective target genes in C. elegans, therefore closing the gap between research approaches using model nematodes and those using target organisms. Considering the still scarcely advanced techniques for genetic engineering of parasitic nematodes, the presented method provides an excellent opportunity for examining the pharmacofunction of anthelmintic targets derived from parasitic nematodes. In parasitic nematodes, experiments at the molecular level are currently not feasible, since in vitro culture and genetic engineering are still in their infancy. In the present study we chose the model organism Caenorhabditis elegans not only as a mere expression system for genes from parasitic nematodes, but used the transformants to examine the functionality of the expressed proteins for mediating anthelmintic effects in vivo. The results of our experiments confirmed that SLO-1 channels mediate the activity of the new anthelmintic drug emodepside and showed that the mode of action is conserved through several nematode species. The chosen method allowed us to examine the functionality of proteins from parasitic nematodes in a defined genetic background. Notably, expression of the parasitic nematode gene in anthelmintic-resistant C. elegans completely restored drug susceptibility. As C. elegans is highly tractable to molecular genetic and pharmacological approaches, the generation of lines expressing the parasite drug target will greatly facilitate structure-function analysis of the interaction between emodepside and ion channels with direct relevance to its anthelmintic properties. In a broader context, the demonstration of C. elegans as a heterologous expression system for functional analysis of parasite proteins further strengthens this as a model for anthelmintic studies.
Collapse
|
19
|
Knox D. Proteases in blood-feeding nematodes and their potential as vaccine candidates. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 712:155-76. [PMID: 21660664 DOI: 10.1007/978-1-4419-8414-2_10] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Parasitic nematodes express and secrete a variety of proteases which they use for many purposes including the penetration of host tissues, digestion of host protein for nutrients, evasion of host immune responses and for internal processes such as tissue catabolism and apoptosis. For these broad reasons they have been examined as possible parasite control targets. Blood-feeding nematodes such as the barber-pole worm Haemonchus contortus that infect sheep and goats and the hookworms, Ancylostoma spp. and Necator americanus, affecting man, use an array of endo- and exopeptidases to digest the blood meal. Haemoglobin digestion occurs by an ordered and partly conserved proteolytic cascade. These proteases are accessible to host immune responses which can block enzyme function and lead to parasite expulsion and/or death. Thus they are receiving attention as components of vaccines against several parasitic nematodes of social and economic importance.
Collapse
Affiliation(s)
- David Knox
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, Scotland, UK.
| |
Collapse
|
20
|
The gene structure and promoter region of the vaccine target aminopeptidase H11 from the blood-sucking nematode parasite of ruminants, Haemonchus contortus. Funct Integr Genomics 2010; 10:589-601. [DOI: 10.1007/s10142-010-0172-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2010] [Revised: 03/29/2010] [Accepted: 04/01/2010] [Indexed: 12/17/2022]
|
21
|
Cantacessi C, Campbell BE, Young ND, Jex AR, Hall RS, Presidente PJA, Zawadzki JL, Zhong W, Aleman-Meza B, Loukas A, Sternberg PW, Gasser RB. Differences in transcription between free-living and CO2-activated third-stage larvae of Haemonchus contortus. BMC Genomics 2010; 11:266. [PMID: 20420710 PMCID: PMC2880303 DOI: 10.1186/1471-2164-11-266] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 04/27/2010] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND The disease caused by Haemonchus contortus, a blood-feeding nematode of small ruminants, is of major economic importance worldwide. The infective third-stage larva (L3) of this gastric nematode is enclosed in a cuticle (sheath) and, once ingested with herbage by the host, undergoes an exsheathment process that marks the transition from the free-living (L3) to the parasitic (xL3) stage. This study explored changes in gene transcription associated with this transition and predicted, based on comparative analysis, functional roles for key transcripts in the metabolic pathways linked to larval development. RESULTS Totals of 101,305 (L3) and 105,553 (xL3) expressed sequence tags (ESTs) were determined using 454 sequencing technology, and then assembled and annotated; the most abundant transcripts encoded transthyretin-like, calcium-binding EF-hand, NAD(P)-binding and nucleotide-binding proteins as well as homologues of Ancylostoma-secreted proteins (ASPs). Using an in silico-subtractive analysis, 560 and 685 sequences were shown to be uniquely represented in the L3 and xL3 stages, respectively; the transcripts encoded ribosomal proteins, collagens and elongation factors (in L3), and mainly peptidases and other enzymes of amino acid catabolism (in xL3). Caenorhabditis elegans orthologues of transcripts that were uniquely transcribed in each L3 and xL3 were predicted to interact with a total of 535 other genes, all of which were involved in embryonic development. CONCLUSION The present study indicated that some key transcriptional alterations taking place during the transition from the L3 to the xL3 stage of H. contortus involve genes predicted to be linked to the development of neuronal tissue (L3 and xL3), formation of the cuticle (L3) and digestion of host haemoglobin (xL3). Future efforts using next-generation sequencing and bioinformatic technologies should provide the efficiency and depth of coverage required for the determination of the complete transcriptomes of different developmental stages and/or tissues of H. contortus as well as the genome of this important parasitic nematode. Such advances should lead to a significantly improved understanding of the molecular biology of H. contortus and, from an applied perspective, to novel methods of intervention.
Collapse
Affiliation(s)
- Cinzia Cantacessi
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia
| | - Bronwyn E Campbell
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia
| | - Neil D Young
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia
| | - Aaron R Jex
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia
| | - Ross S Hall
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia
| | | | - Jodi L Zawadzki
- Department of Primary Industries, Attwood, Victoria, Australia
| | - Weiwei Zhong
- Department of Biochemistry and Cell Biology, Rice University, Houston, Texas, USA
| | | | - Alex Loukas
- James Cook University, Cairns, Queensland, Australia
| | - Paul W Sternberg
- Biology Division, California Institute of Technology, Pasadena, California, USA
| | - Robin B Gasser
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia
| |
Collapse
|
22
|
Construction and characterization of subtractive stage-specific expressed sequence tag (EST) libraries of the pinewood nematode Bursaphelenchus xylophilus. Genomics 2009; 94:70-7. [DOI: 10.1016/j.ygeno.2009.03.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 02/27/2009] [Accepted: 03/06/2009] [Indexed: 11/22/2022]
|
23
|
A cathepsin L-like protease from Strongylus vulgaris: An orthologue of Caenorhabditis elegans CPL-1. Exp Parasitol 2009; 121:293-9. [DOI: 10.1016/j.exppara.2008.11.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Accepted: 11/03/2008] [Indexed: 11/20/2022]
|
24
|
Meyvis Y, Callewaert N, Gevaert K, Timmerman E, Van Durme J, Schymkowitz J, Rousseau F, Vercruysse J, Claerebout E, Geldhof P. Hybrid N-glycans on the host protective activation-associated secreted proteins of Ostertagia ostertagi and their importance in immunogenicity. Mol Biochem Parasitol 2008; 161:67-71. [DOI: 10.1016/j.molbiopara.2008.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 05/14/2008] [Accepted: 05/14/2008] [Indexed: 10/22/2022]
|
25
|
Four abundant novel transcript genes from Toxocara canis with unrelated coding sequences share untranslated region tracts implicated in the control of gene expression. Mol Biochem Parasitol 2008; 162:60-70. [PMID: 18703093 DOI: 10.1016/j.molbiopara.2008.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Revised: 07/14/2008] [Accepted: 07/14/2008] [Indexed: 11/23/2022]
Abstract
The Toxocara canis "abundant novel transcripts" (ant) are four highly expressed products, constituting >18% of ESTs from the infective stage of this widely prevalent nematode parasite. Using 5' RACE, we determined full-length sequences for each ant gene, between 1.8 and 2.8kb. The four genes (termed ant-3, -5, -30 and -34), share no coding sequence similarity, although their 3'UTRs (untranslated regions) are homologous. Predicted ANT-5 and ANT-30 proteins show distant similarity to RNA regulatory proteins, RNA-dependent RNA polymerase and DEAH-box helicase, respectively. Surprisingly, ant-3 appears to be bi-cistronic, encoding two ORFs (ANT-3.1 and -3.2), each with a predicted N-terminal signal sequence. Antibodies raised to recombinant proteins did not react with native parasite products, indicating that protein expression did not accord with transcript abundance. However, antibody reactivity to two gene products (ANT-3.1 and ANT-34) was present in patient sera, suggesting that these proteins are synthesized later in infection. To test whether 3'UTRs may regulate expression, the ant-34 3'UTR sequence was inserted adjacent to enhanced green fluorescent protein (EGFP) for transformation of Caenorhabditis elegans. The ant-34 3'UTR greatly reduced EGFP expression, inhibiting both transcription and translation. We identified a tract in this UTR with significant sequence complementarity to the C. elegans micro-RNA lin-4. While infective stage parasites stockpile high levels of the ant transcripts, we suggest that translation is repressed, possibly by a mechanism involving 3' UTR motifs shared by the four genes.
Collapse
|
26
|
Maizels RM, Gomez-Escobar N, Prieto-Lafuente L, Murray J, Aebischer T. Expression of helminth genes in Leishmania: an experimental transfection system to test immunological function. Parasite Immunol 2008; 30:195-201. [PMID: 18324922 DOI: 10.1111/j.1365-3024.2007.00997.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Functional analysis of genes from parasitic helminths requires, at the present time, heterologous expression. We have adapted the well-characterized system of transfection in Leishmania protozoal parasites, as a means of analysing the effect of single filarial genes on the mammalian immune system. For example, testing the function of the Brugia malayi abundant larval transcript (ALT) gene-transfected Leishmania mexicana were found to be significantly more virulent in macrophages in vitro. The course of infection in vivo is also aggravated by expression of the ALT gene. Examples are also given of transgenes which reduced in vitro growth within macrophages, as well as others which exert no effect on the protozoal parasitism. Thus, Leishmania transfection provides a tractable system to analyse helminth gene function within the context of the host immune system.
Collapse
Affiliation(s)
- R M Maizels
- Institute of Immunology and Infection Research, University of Edinburgh, Ashworth Laboratories, Edinburgh, UK.
| | | | | | | | | |
Collapse
|
27
|
Geldhof P, De Maere V, Vercruysse J, Claerebout E. Recombinant expression systems: the obstacle to helminth vaccines? Trends Parasitol 2007; 23:527-32. [DOI: 10.1016/j.pt.2007.08.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Revised: 08/14/2007] [Accepted: 08/14/2007] [Indexed: 01/06/2023]
|