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Xiang Q, Wan Y, Pu X, Lu M, Xu L, Yan R, Li X, Song X. Protective efficacy of Eimeria maxima EmLPL and EmTregIM-1 against homologous challenge in chickens. Poult Sci 2024; 103:103865. [PMID: 38810564 PMCID: PMC11166879 DOI: 10.1016/j.psj.2024.103865] [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: 03/30/2024] [Revised: 05/07/2024] [Accepted: 05/13/2024] [Indexed: 05/31/2024] Open
Abstract
Chicken coccidiosis has inflicted significant economic losses upon the poultry industry. The primary strategies for preventing and controlling chicken coccidiosis include anticoccidial drugs and vaccination. However, these approaches face limitations, such as drug residues and resistance associated with anticoccidial drugs, and safety concerns related to live vaccines. Consequently, the urgent development of innovative vaccines, such as subunit vaccines, is imperative. In previous study, we screened 2 candidate antigens: Eimeria maxima lysophospholipase (EmLPL) and E. maxima regulatory T cell inducing molecule 1 (EmTregIM-1). To investigate the immune protective effect of the 2 candidate antigens against Eimeria maxima (E. maxima) infection, we constructed recombinant plasmids, namely pET-28a-EmLPL and pET-28a-EmTregIM-1, proceeded to induce the expression of recombinant proteins of EmLPL (rEmLPL) and EmTregIM-1 (rEmTregIM-1). The immunogenic properties of these proteins were confirmed through western blot analysis. Targeting EmLPL and EmTregIM-1, we developed subunit vaccines and encapsulated them in PLGA nanoparticles, resulting in nano-vaccines: PLGA-rEmLPL and PLGA-rEmTregIM-1. The efficacy of these vaccines was assessed through animal protection experiments. The results demonstrated that rEmLPL and rEmTregIM-1 were successfully recognized by anti-E. maxima chicken sera and His-conjugated mouse monoclonal antibodies. Immunization with both subunit and nano-vaccines containing EmLPL and EmTregIM-1 markedly mitigated weight loss and reduced oocyst shedding in chickens infected with E. maxima. Furthermore, the anticoccidial indexes (ACI) for both rEmLPL and PLGA-rEmLPL exceeded 160, whereas those for rEmTregIM-1 and PLGA-rEmTregIM-1 were above 120 but did not reach 160, indicating superior protective efficacy of the rEmLPL and PLGA-rEmLPL formulations. By contrast, the protection afforded by rEmTregIM-1 and PLGA-rEmTregIM-1 was comparatively lower. Thus, EmLPL is identified as a promising candidate antigen for vaccine development against E. maxima infection.
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Affiliation(s)
- Quanjia Xiang
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yun Wan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xianglin Pu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Mingmin Lu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Lixin Xu
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Ruofeng Yan
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiangrui Li
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiaokai Song
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, PR China.
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Sharma MK, Kim WK. Coccidiosis in Egg-Laying Hens and Potential Nutritional Strategies to Modulate Performance, Gut Health, and Immune Response. Animals (Basel) 2024; 14:1015. [PMID: 38612254 PMCID: PMC11010854 DOI: 10.3390/ani14071015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024] Open
Abstract
Avian coccidiosis, despite advancements in management, nutrition, genetics, and immunology, still remains the most impactful disease, imposing substantial economic losses to the poultry industry. Coccidiosis may strike any avian species, and it may be mild to severe, depending on the pathogenicity of Eimeria spp. and the number of oocysts ingested by the bird. Unlike broilers, low emphasis has been given to laying hens. Coccidiosis in laying hens damages the gastrointestinal tract and causes physiological changes, including oxidative stress, immunosuppression, and inflammatory changes, leading to reduced feed intake and a drastic drop in egg production. Several countries around the world have large numbers of hens raised in cage-free/free-range facilities, and coccidiosis has already become one of the many problems that producers have to face in the future. However, limited research has been conducted on egg-laying hens, and our understanding of the physiological changes following coccidiosis in hens relies heavily on studies conducted on broilers. The aim of this review is to summarize the effect of coccidiosis in laying hens to an extent and correlate it with the physiological changes that occur in broilers following coccidiosis. Additionally, this review tries to explore the nutritional strategies successfully used in broilers to mitigate the negative effects of coccidiosis in improving the gut health and performance of broilers and if they can be used in laying hens.
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Affiliation(s)
| | - Woo Kyun Kim
- Department of Poultry Science, University of Georgia, Athens, GA 30602, USA;
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3
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Ramalingam V, Muthusamy R, Bohra K, Palavesam A, Gopal D. Cloning, expression and purification of Eimeria maxima gametocyte antigen-EmGam56 for control of poultry coccidiosis. J Parasit Dis 2023; 47:773-777. [PMID: 38009159 PMCID: PMC10667185 DOI: 10.1007/s12639-023-01610-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 06/09/2023] [Indexed: 11/28/2023] Open
Abstract
Poultry coccidiosis is an important devitalizing enteric protozoan disease caused by a group of obligatory intracellular apicomplexan parasites of the Genus Eimeria contributing to major economic loss in commercial poultry worldwide. As the current method of chemotherapeutic control using ionophores in feed had led to development of drug resistant isolates, the need for development of prophylactic vaccines is the most viable alternate and eco-friendly control strategy as on date. Of the several candidate vaccines, the EmGam 56 is one of the most promising candidates which protect the birds against E. maxima, E. tenella and E. acervulina, the three most pathogenic coccidian species infecting commercial chicken. EmGam56 is a major wall forming component of macrogametocyte of E. maxima and a candidate with high immunogenicity and low virulence. The present study was planned and carried out for the generation of E.coli expressed recombinant gametocyte antigen-EmGam56 using pET 28(a+) as cloning vector and BL21 DE3 (pLysS) as prokaryotic expression system in a Bio-fermentor (New Brunswick™ Scientific BioFlo 310). The recombinant protein was purified by conventional (Ammonium sulphate precipitation) and by automatic purification system (AKTA prime) in Ni-NTA column for a planned immunization trial with experimental chickens.
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Affiliation(s)
- Vijayashanthi Ramalingam
- Translational Research Platform for Veterinary Biologicals (TRPVB), Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, 600051 Chennai, India
| | - Raman Muthusamy
- Translational Research Platform for Veterinary Biologicals (TRPVB), Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, 600051 Chennai, India
- Department of Microbiology, Centre for Infectious Diseases, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Chennai, 600077 India
| | - Kasthuri Bohra
- Translational Research Platform for Veterinary Biologicals (TRPVB), Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, 600051 Chennai, India
| | - Azhahianambi Palavesam
- Translational Research Platform for Veterinary Biologicals (TRPVB), Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, 600051 Chennai, India
| | - Dhinakarraj Gopal
- Translational Research Platform for Veterinary Biologicals (TRPVB), Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, 600051 Chennai, India
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Wang H, Logue CM, Nolan LK, Lin J. Assessment of an Enterobactin Conjugate Vaccine in Layers to Protect Their Offspring from Colibacillosis. Pathogens 2023; 12:1002. [PMID: 37623962 PMCID: PMC10458604 DOI: 10.3390/pathogens12081002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/18/2023] [Accepted: 07/28/2023] [Indexed: 08/26/2023] Open
Abstract
Colibacillosis, caused by avian pathogenic Escherichia coli (APEC), is an important infectious disease in chickens and a major cause of mortality in young chicks. Therefore, protecting young chickens from colibacillosis is important for improving welfare and productivity in the poultry industry. Recently, we developed a novel enterobactin (Ent) conjugate vaccine that could induce high titers of anti-Ent immunoglobulin Y (IgY) in chicken serum and consequently mitigate the organ lesions caused by APEC infection. Considering that maternal immunization is a practical approach to confer instant immune protection to the hatchlings, in this study, we immunized breeder hens with the Ent conjugate vaccine and evaluated the maternal immune protection on the progenies challenged with APEC. Three doses of the vaccine induced high titers of anti-Ent IgY in the hens (about 16- and 64-fold higher than the control group in the sera and egg yolks, respectively), resulting in an eight-fold of increase in anti-Ent IgY in the sera of progenies. However, the anti-Ent maternal immunity did not display significant protection against APEC challenge in the young chicks as there was no significant difference in APEC load (in liver, lung, and spleen) or organ lesions (in heart, liver, spleen, lung, and air sac) between the vaccinated and control groups. In future studies, the APEC infection model needs to be optimized to exhibit proper pathogenicity of APEC, and the maternal immunization regimen can be further improved to boost the maternally derived anti-Ent IgY in the hatchlings.
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Affiliation(s)
- Huiwen Wang
- Department of Animal Science, University of Tennessee, Knoxville, TN 37919, USA
| | - Catherine M. Logue
- Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Lisa K. Nolan
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Jun Lin
- Department of Animal Science, University of Tennessee, Knoxville, TN 37919, USA
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Xiao J, Chen H, Zheng R, Pu J, Gu X, Xie Y, He R, Xu J, Jing B, Peng X, Yang G. Recombinant GMA56 and ROP17 of Eimeria magna conferred protection against infection by homologous species. Front Immunol 2023; 13:1037949. [PMID: 36713437 PMCID: PMC9879601 DOI: 10.3389/fimmu.2022.1037949] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 12/27/2022] [Indexed: 01/15/2023] Open
Abstract
One of the most common rabbits coccidia species, Eimeria magna is mainly parasitic in the ileal and jejunal epithelial cells. E. magna infection can affect the growth performance of rabbits or cause other secondary diseases. Traditional methods of anticoccidial treatment typically result in drug resistance and drug residue. Therefore, vaccination is a promising alternative. Gametocyte antigen 56 (GAM56) and rhoptry kinase family proteins (ROPs) are involved in oocyst wall formation and parasite invasion, respectively. A virulence factor, ROP17 contains a serine/threonine kinase catalytic domain. In this study, recombinant E. magna GAM56 (rEmGAM56) and ROP17 (rEmROP17) proteins were obtained from a prokaryotic expression system and their reactogenicity was investigated with immunoblotting. To assess the potential of rEmGAM56 and rEmROP17 as coccidiosis vaccines, New Zealand White rabbits were subcutaneously immunized with 100 μg rEmGAM56 (rGC group) or rEmROP17 (rRC group) twice at 2-week intervals followed by homologous oocyst challenge. The rabbit serum was collected weekly to detect the specific antibody levels. The cytokine levels of pre-challenge serum were measured by enzyme-linked immunosorbent assay and the rabbits were observed and recorded post-challenge for the onset of clinical symptoms. The weight gain, oocyst output, and feed conversion ratio were calculated at the end of the experiment. The results showed that both rEmGAM56 and rEmROP17 had good reactogenicity. The rEmGAM56- or rEmROP17-immunized rabbits had milder clinical symptoms and feed conversion ratios of 3.27:1 and 3.37:1, respectively. The rEmGAM56-immunized rabbits had 81.35% body weight gain and 63.85% oocyst output reduction; the rEmROP17-immunized rabbits had 79.03% body weight gain and 80.10% oocyst output reduction. The ACI of rGC and rRC groups were 162.35 and 171.03, respectively. The specific antibody levels increased rapidly after immunization. Significantly increased interleukin (IL)-2, interferon (IFN)-γ, and IL-17 levels were evident in the rGC and rRC groups (p < 0.05). The rEmGAM56 and rEmROP17 elicited humoral and cellular responses, which protected against E. magna infection in rabbits. Thus, rEmGAM56 and rEmROP17 are potential vaccine candidates against E. magna, and rEmROP17 performed better than rEmGAM56.
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Affiliation(s)
- Jie Xiao
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Hao Chen
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ruoyu Zheng
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Jiayan Pu
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xiaobin Gu
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Yue Xie
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ran He
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Jing Xu
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Bo Jing
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xuerong Peng
- Department of Chemistry, College of Life and Basic Science, Sichuan Agricultural University, Chengdu, China
| | - Guangyou Yang
- Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China,*Correspondence: Guangyou Yang,
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6
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Wang M, Tian D, Xu L, Lu M, Yan R, Li X, Song X. Protective efficacy induced by Eimeria maxima rhomboid-like protein 1 against homologous infection. Front Vet Sci 2023; 9:1049551. [PMID: 36686197 PMCID: PMC9845710 DOI: 10.3389/fvets.2022.1049551] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 12/12/2022] [Indexed: 01/06/2023] Open
Abstract
Introduction Avian coccidiosis, caused by apicomplexan protozoa belonging to the Eimeria genus, is considered one of the most important diseases in the intensive poultry industry worldwide. Due to the shortcomings of live anticoccidial vaccines and drugs, the development of novel anticoccidial vaccines is increasingly urgent. Methods Eimeria maxima rhomboid-like protein 1 (EmROM1), an invasion-related molecule, was selected as a candidate antigen to evaluate its protective efficacy against E. maxima in chickens. Firstly, the prokaryotic recombinant plasmid pET-32a-EmROM1 was constructed to prepare EmROM1 recombinant protein (rEmROM1), which was used as a subunit vaccine. The eukaryotic recombinant plasmid pVAX1.0-EmROM1 (pEmROM1) was constructed as a DNA vaccine. Subsequently, 2-week-old chicks were separately vaccinated with the rEmROM1 and pEmROM1 twice every 7 days. One week post the booster vaccination, induced cellular immune responses were determined by evaluating the mRNA level of cytokines including IL-2, IFN-γ, IL-4, IL-10, TGF-β, IL-17, and TNFSF15, as well as the percentages of CD4+ and CD8+ T cells from spleens of vaccinated chickens. Specific serum antibody level in the vaccinated chickens was determined to assess induced humoral immune responses. Finally, the protective efficacy of EmROM1 was evaluated by a vaccination-challenge trial. Results EmROM1 vaccination significantly upregulated the cytokine transcription levels and CD4+/CD8+ T cell percentages in vaccinated chickens compared with control groups, and also significantly increased the levels of serum-specific antibodies in vaccinated chickens. The animal trial showed that EmROM1 vaccination significantly reduced oocyst shedding, enteric lesions, and weight loss of infected birds compared with the controls. The anticoccidial index (ACI) from the rEmROM-vaccination group and pEmROM1-vaccination group were 174.11 and 163.37, respectively, showing moderate protection against E. maxima infection. Discussion EmROM1 is an effective candidate antigen for developing DNA or subunit vaccines against avian coccidiosis.
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El-Kafrawy SA, Abbas AT, Oelkrug C, Tahoon M, Ezzat S, Zumla A, Azhar EI. IgY antibodies: The promising potential to overcome antibiotic resistance. Front Immunol 2023; 14:1065353. [PMID: 36742328 PMCID: PMC9896010 DOI: 10.3389/fimmu.2023.1065353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 01/05/2023] [Indexed: 01/22/2023] Open
Abstract
Antibiotic resistant bacteria are a growing threat to global health security. Whilst the emergence of antimicrobial resistance (AMR) is a natural phenomenon, it is also driven by antibiotic exposure in health care, agriculture, and the environment. Antibiotic pressure and inappropriate use of antibiotics are important factors which drive resistance. Apart from their use to treat bacterial infections in humans, antibiotics also play an important role in animal husbandry. With limited antibiotic options, alternate strategies are required to overcome AMR. Passive immunization through oral, nasal and topical administration of egg yolk-derived IgY antibodies from immunized chickens were recently shown to be effective for treating bacterial infections in animals and humans. Immunization of chickens with specific antigens offers the possibility of creating specific antibodies targeting a wide range of antibiotic-resistant bacteria. In this review, we describe the growing global problem of antimicrobial resistance and highlight the promising potential of the use of egg yolk IgY antibodies for the treatment of bacterial infections, particularly those listed in the World Health Organization priority list.
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Affiliation(s)
- Sherif A El-Kafrawy
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Clinical Pathology, National Liver Institute, Menoufia University, Shebin El-Kom, Egypt
| | - Aymn T Abbas
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Biotechnology Research Laboratories, Gastroenterology, Surgery Centre, Mansoura University, Mansoura, Egypt
| | | | - Marwa Tahoon
- Epidemiology and Preventive Medicine Department, National Liver Institute, Menoufia University, Shebin El-Kom, Egypt
| | - Sameera Ezzat
- Epidemiology and Preventive Medicine Department, National Liver Institute, Menoufia University, Shebin El-Kom, Egypt.,MARC for Medical Services and Scientific Research, 6th of October City, Giza, Egypt
| | - Alimuddin Zumla
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Infection, Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, United Kingdom.,National Institute for Health and Care Research (NIHR) Biomedical Research Centre, University College London Hospitals, London, United Kingdom
| | - Esam I Azhar
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
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Yang X, Song X, Liu J, Chen Q, An T, Liu Q. Protection of hatchlings against coccidiosis by maternal antibodies to four recombinant proteins of Eimeria tenella, Eimeria acervulina and Eimeria maxima. Vet Parasitol 2022; 312:109813. [PMID: 36343529 DOI: 10.1016/j.vetpar.2022.109813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022]
Abstract
Maternally derived IgG antibodies to protective Eimeria antigens have great potential to control chicken coccidiosis and multivalent vaccines are more practical to resist against co-infection with several species of Eimeria under natural conditions. In this study, five good protective antigens of Eimeria species were combined into two combinations based on previous studies, namely C1(EtROPK-Eten5-A, EtGAM22, Ea3-1E and EmGAM56) and C2(EtM2AP and EtGAM22, Ea3-1E and EmGAM56). Then, five antigens were expressed in the Escherichia coli system and purified to inoculate breeding hens. After three times immunization, the specific antibodies could sustain for 11 and 10 weeks in hens' plasma and egg yolk, respectively. Moreover, maternally derived antibodies against recombinant proteins could retain for 14 days in hatchlings' serum. Then, protective efficacies of specific antibodies on hatchlings against mixed infection of E. tenella, E. acervulina and E. maxima were evaluated. The results showed that the hatchlings of the immunized hens had a higher survival rate on day 7 of hatching. Moreover, body weight gains within the hatchlings of immunized hens were higher than those of unvaccinated hens on 7 days (C1: p = 0.0744; C2: p = 0.4020) and 14 days (p < 0.0001). Moreover, hatchlings from vaccinated hens showed significantly alleviated lesion scores in the small intestine and duodenum at day 7 (p < 0.01) and day 14 (C1: p < 0.05). Particularly, the number of oocyst excretion from hatchlings of immunized hens was significantly reduced at day 7 (p < 0.0001) and day 14 (p < 0.0001). Our findings suggest that the maternal immunization with multivalent recombinant vaccines has the potential to be transmission blocking vaccines against mixed infection of Eimeria.
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Affiliation(s)
- Xu Yang
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China.
| | - Xingju Song
- College of Animal Science and Technology, Guangxi University, Nanning 530004, PR China.
| | - Jing Liu
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China.
| | - Qingzhong Chen
- HLINTE Biological Technology Company, Tianjin 301702, PR China.
| | - Tongwei An
- HLINTE Biological Technology Company, Tianjin 301702, PR China.
| | - Qun Liu
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China.
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Xiao J, Zheng R, Bai X, Pu J, Chen H, Gu X, Xie Y, He R, Xu J, Jing B, Peng X, Yang G. Preliminary evaluation of the protective effects of recombinant AMA1 and IMP1 against Eimeria stiedae infection in rabbits. Parasit Vectors 2022; 15:400. [PMID: 36316714 PMCID: PMC9623944 DOI: 10.1186/s13071-022-05492-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 09/16/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Eimeria stiedae parasitizes the bile duct, causing hepatic coccidiosis in rabbits. Coccidiosis control using anticoccidials led to drug resistance and residues; therefore, vaccines are required as an alternative control strategy. Apical membrane antigen 1 (AMA1) and immune mapped protein 1 (IMP1) are surface-located proteins that might contribute to host cell invasion, having potential as candidate vaccine antigens. METHODS Herein, we cloned and expressed the E. stiedae EsAMA1 and EsIMP1 genes. The reactogenicity of recombinant AMA1 (rEsAMA1) and IMP1 (rEsIMP1) proteins were investigated using immunoblotting. For the vaccination-infection trial, rabbits were vaccinated with rEsAMA1 and rEsIMP1 (both 100 μg/rabbit) twice at 2-week intervals. After vaccination, various serum cytokines were measured. The protective effects of rEsAMA1 and rEsIMP1 against E. stiedae infection were assessed using several indicators. Sera were collected weekly to detect the specific antibody levels. RESULTS Both rEsAMA1 and rEsIMP1 showed strong reactogenicity. Rabbits vaccinated with rEsAMA1 and rEsIMP1 displayed significantly increased serum IL-2 (F (4, 25) = 9.53, P = 0.000), IL-4 (F (4, 25) = 7.81, P = 0.000), IL-17 (F (4, 25) = 8.55, P = 0.000), and IFN-γ (F (4, 25) = 6.89, P = 0.001) levels; in the rEsIMP1 group, serum TGF-β1 level was also elevated (F (4, 25) = 3.01, P = 0.037). After vaccination, the specific antibody levels increased and were maintained at a high level. The vaccination-infection trial showed that compared with the positive control groups, rabbits vaccinated with the recombinant proteins showed significantly reduced oocyst output (F (5, 54) = 187.87, P = 0.000), liver index (F (5, 54) = 37.52, P = 0.000), and feed conversion ratio; body weight gain was significantly improved (F (5, 54) = 28.82, P = 0.000). CONCLUSIONS rEsAMA1 and rEsIMP1 could induce cellular and humoral immunity, protecting against E. stiedae infection. Thus, rEsAMA1 and rEsIMP1 are potential vaccine candidates against E. stiedae.
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Affiliation(s)
- Jie Xiao
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Ruoyu Zheng
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Xin Bai
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Jiayan Pu
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Hao Chen
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Xiaobin Gu
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Yue Xie
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Ran He
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Jing Xu
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Bo Jing
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Xuerong Peng
- grid.80510.3c0000 0001 0185 3134Department of Chemistry, College of Life and Basic Science, Sichuan Agricultural University, Wenjiang, 611130 China
| | - Guangyou Yang
- grid.80510.3c0000 0001 0185 3134Department of Parasitology, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, 611130 China
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Eimeria maxima Rhomboid-like Protein 5 Provided Partial Protection against Homologous Challenge in Forms of Recombinant Protein and DNA Plasmid in Chickens. Vaccines (Basel) 2021; 10:vaccines10010032. [PMID: 35062693 PMCID: PMC8781051 DOI: 10.3390/vaccines10010032] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/17/2021] [Accepted: 12/23/2021] [Indexed: 11/17/2022] Open
Abstract
Eimeria maxima (E. maxima) is one of the most prevalent species that causes chicken coccidiosis on chicken farms. During apicomplexan protozoa invasion, rhomboid-like proteins (ROMs) cleave microneme proteins (MICs), allowing the parasites to fully enter the host cells, which suggests that ROMs have the potential to be candidate antigens for the development of subunit or DNA vaccines against coccidiosis. In this study, a recombinant protein of E. maxima ROM5 (rEmROM5) was expressed and purified and was used as a subunit vaccine. The eukaryotic expression plasmid of pVAX-EmROM5 was constructed and was used as a DNA vaccine. Chickens who were two weeks old were vaccinated with the rEmROM5 and pVAX-EmROM5 vaccines twice, with a one-week interval separating the vaccination periods. The transcription and expression of pVAX-EmROM5 in the injected sites were detected through reverse transcription PCR (RT-PCR) and Western blot (WB) assays. The cellular and humoral immune responses that were induced by EmROM5 were determined by detecting the proportion of CD4+ and CD8+ T lymphocytes, the cytokine levels, and the serum antibody levels. Finally, vaccination-challenge trials were conducted to evaluate the protective efficacy of EmROM5 in forms of the recombinant protein (rEmROM5) and in the DNA plasmid (pVAX-EmROM5) separately. The results showed that rEmROM5 was about 53.64 kDa, which was well purified and recognized by the His-Tag Mouse Monoclonal antibody and the chicken serum against E. maxima separately. After vaccination, pVAX-EmROM5 was successfully transcribed and expressed in the injected sites of the chickens. Vaccination with rEmROM5 or pVAX-EmROM5 significantly promoted the proportion of CD4+/CD3+ and CD8+/CD3+ T lymphocytes, the mRNA levels of the cytokines IFN-γ, IL-2, IL-4, IL-17, TNF SF15, and IL-10, and specific IgG antibody levels compared to the control groups. The immunization also significantly reduced the weight loss, oocyst production, and intestinal lesions that are caused by E. maxima infection. The anticoccidial index (ACI)s of the vaccinated groups were beyond 160, showing moderate protection against E. maxima infection. In summary, EmROM5 was able to induce a robust immune response and effective protection against E. maxima in chickens in the form of both a recombinant protein and DNA plasmid. Hence, EmROM5 could be used as a candidate antigen for DNA vaccines and subunit vaccines against avian coccidiosis.
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Juárez-Estrada MA, Tellez-Isaias G, Sánchez-Godoy FD, Alonso-Morales RA. Immunotherapy With Egg Yolk Eimeria sp.-Specific Immunoglobulins in SPF Leghorn Chicks Elicits Successful Protection Against Eimeria tenella Infection. Front Vet Sci 2021; 8:758379. [PMID: 34859090 PMCID: PMC8632257 DOI: 10.3389/fvets.2021.758379] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 10/14/2021] [Indexed: 12/28/2022] Open
Abstract
Avian coccidiosis is the first to most economically important parasite disease affecting poultry industries worldwide. Current prevention measures are largely based upon prophylactic chemotherapy supplemented by the application of live attenuated or wild-type parasite vaccines. However, the rising appearance of drug resistance, consumer's concern for antibiotics use in poultry production and higher manufacturing cost of live vaccines has driven to adopt new technologies aimed at increasing animal health and production efficiency. Supplementing chickens with egg yolk Eimeria sp.-specific immunoglobulins can be a viable alternative to avoid severe outbreaks of the disease. Twelve-week-old SPF White Leghorn chickens were experimentally infected with a large dose of E. tenella. During the prepatent period, the birds were supplemented by oral gavage with 60 or 120 mg/bird of hyperimmune egg yolk Eimeria species-specific immunoglobulins Y (Supracox®, SC) on a daily basis. The animals were euthanized 7 days post-infection (PI) and their passive immune protection was evaluated. Birds treated with 120 mg/bird of SC showed more viability, increased body weight gain (BWG), a normal hematocrit level (HCT), reduced oocyst output per gram of feces (OPG) or cecal tissue (OPGC), and fewer cecal lesions compared to the untreated infected (UI) control group. Birds supplemented with 60 mg/bird of SC did not show any significant difference on BWG, HCT, OPG, OPGC, and cecal lesion score when compared with the UI group. An ELISA test of the SC showed a weak cross-reactivity of IgY toward two asexual zoite stages of E. tenella. Western blot analysis of the sporozoite with SC showed few antigens barely recognized, while more stained bands were detected in the merozoite (≈82, ≈60, ≈54, ≈40, ≈38, ≈27.5, and ≈13 kDa). Oral immunotherapy using egg yolk polyclonal IgYs against Eimeria sp. represents an effective and natural resource against severe E. tenella infection favoring the gradual withdrawal of the anticoccidial drugs and antibiotics.
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Affiliation(s)
- Marco A Juárez-Estrada
- Departamento de Medicina y Zootecnia de Aves, FMVZ, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Departamento de Genética y Bioestadística, FMVZ, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | | | - Félix D Sánchez-Godoy
- Departamento de Medicina y Zootecnia de Aves, FMVZ, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Rogelio A Alonso-Morales
- Departamento de Genética y Bioestadística, FMVZ, Universidad Nacional Autónoma de México, Mexico City, Mexico
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Lee L, Samardzic K, Wallach M, Frumkin LR, Mochly-Rosen D. Immunoglobulin Y for Potential Diagnostic and Therapeutic Applications in Infectious Diseases. Front Immunol 2021; 12:696003. [PMID: 34177963 PMCID: PMC8220206 DOI: 10.3389/fimmu.2021.696003] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 05/26/2021] [Indexed: 01/14/2023] Open
Abstract
Antiviral, antibacterial, and antiparasitic drugs and vaccines are essential to maintaining the health of humans and animals. Yet, their production can be slow and expensive, and efficacy lost once pathogens mount resistance. Chicken immunoglobulin Y (IgY) is a highly conserved homolog of human immunoglobulin G (IgG) that has shown benefits and a favorable safety profile, primarily in animal models of human infectious diseases. IgY is fast-acting, easy to produce, and low cost. IgY antibodies can readily be generated in large quantities with minimal environmental harm or infrastructure investment by using egg-laying hens. We summarize a variety of IgY uses, focusing on their potential for the detection, prevention, and treatment of human and animal infections.
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Affiliation(s)
- Lucia Lee
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, United States
| | - Kate Samardzic
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, United States
| | - Michael Wallach
- School of Life Sciences, University of Technology, Sydney, NSW, Australia
| | | | - Daria Mochly-Rosen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA, United States
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Mtshali SA, Adeleke MA. A review of adaptive immune responses to Eimeria tenella and Eimeria maxima challenge in chickens. WORLD POULTRY SCI J 2020. [DOI: 10.1080/00439339.2020.1833693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- S. A. Mtshali
- Discipline of Genetics, School of Life Sciences, University of Kwa-Zulu Natal, Durban, South Africa
| | - M. A. Adeleke
- Discipline of Genetics, School of Life Sciences, University of Kwa-Zulu Natal, Durban, South Africa
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14
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Abbas AT, El-Kafrawy SA, Sohrab SS, Tabll AA, Hassan AM, Iwata-Yoshikawa N, Nagata N, Azhar EI. Anti-S1 MERS-COV IgY Specific Antibodies Decreases Lung Inflammation and Viral Antigen Positive Cells in the Human Transgenic Mouse Model. Vaccines (Basel) 2020; 8:vaccines8040634. [PMID: 33139631 PMCID: PMC7712919 DOI: 10.3390/vaccines8040634] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 10/21/2020] [Accepted: 10/28/2020] [Indexed: 02/07/2023] Open
Abstract
The Middle East respiratory syndrome coronavirus (MERS-CoV) was identified in 2012 and causes severe and often fatal acute respiratory illness in humans. No approved prophylactic and therapeutic interventions are currently available. In this study, we have developed egg yolk antibodies (immunoglobulin Y (IgY)) specific for MERS-CoV spike protein (S1) in order to evaluate their neutralizing efficiency against MERS-CoV infection. S1-specific immunoglobulins were produced by injecting chickens with purified recombinant S1 protein of MERS-CoV at a high titer (5.7 mg/mL egg yolk) at week 7 post immunization. Western blotting and immune-dot blot assays demonstrated that the IgY antibody specifically bound to the MERS-CoV S1 protein. Anti-S1 antibodies were also able to recognize MERS-COV inside cells, as demonstrated by an immunofluorescence assay. Plaque reduction and microneutralization assays showed the neutralization of MERS-COV in Vero cells by anti-S1 IgY antibodies and non-significantly reduced virus titers in the lungs of MERS-CoV-infected mice during early infection, with a nonsignificant decrease in weight loss. However, a statistically significant (p = 0.0196) quantitative reduction in viral antigen expression and marked reduction in inflammation were observed in lung tissue. Collectively, our data suggest that the anti-MERS-CoV S1 IgY could serve as a potential candidate for the passive treatment of MERS-CoV infection.
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Affiliation(s)
- Aymn T Abbas
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Biotechnology Research Laboratories, Gastroenterology, Surgery Centre, Mansoura University, Mansoura 35511, Egypt
| | - Sherif A El-Kafrawy
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Clinical Pathology, National Liver Institute, Menoufiya University, Shebin El-Kom 32511, Egypt
| | - Sayed Sartaj Sohrab
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Ashraf A Tabll
- Genetic Engineering and Biotechnology Division, Microbial Biotechnology Department (Biomedical Technology Group), National Research Centre, Dokki 12622, Egypt
- Department of Immunology, Egypt Center for Research and Regenerative Medicine (ECRRM), Cairo 11517, Egypt
| | - Ahmed M Hassan
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Naoko Iwata-Yoshikawa
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
| | - Noriyo Nagata
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
| | - Esam I Azhar
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21589, Saudi Arabia
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15
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Anti-S1 MERS-COV IgY Specific Antibodies Decreases Lung Inflammation and Viral Antigen Positive Cells in the Human Transgenic Mouse Model. Vaccines (Basel) 2020. [PMID: 33139631 DOI: 10.3390/vaccines8040634.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The Middle East respiratory syndrome coronavirus (MERS-CoV) was identified in 2012 and causes severe and often fatal acute respiratory illness in humans. No approved prophylactic and therapeutic interventions are currently available. In this study, we have developed egg yolk antibodies (immunoglobulin Y (IgY)) specific for MERS-CoV spike protein (S1) in order to evaluate their neutralizing efficiency against MERS-CoV infection. S1-specific immunoglobulins were produced by injecting chickens with purified recombinant S1 protein of MERS-CoV at a high titer (5.7 mg/mL egg yolk) at week 7 post immunization. Western blotting and immune-dot blot assays demonstrated that the IgY antibody specifically bound to the MERS-CoV S1 protein. Anti-S1 antibodies were also able to recognize MERS-COV inside cells, as demonstrated by an immunofluorescence assay. Plaque reduction and microneutralization assays showed the neutralization of MERS-COV in Vero cells by anti-S1 IgY antibodies and non-significantly reduced virus titers in the lungs of MERS-CoV-infected mice during early infection, with a nonsignificant decrease in weight loss. However, a statistically significant (p = 0.0196) quantitative reduction in viral antigen expression and marked reduction in inflammation were observed in lung tissue. Collectively, our data suggest that the anti-MERS-CoV S1 IgY could serve as a potential candidate for the passive treatment of MERS-CoV infection.
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Wiedmer S, Kurth T, Buder U, Bleischwitz S, Entzeroth R, Kurth M. Correlative light and electron microscopy of wall formation in Eimeria nieschulzi. Parasitol Res 2020; 119:2667-2678. [PMID: 32627078 PMCID: PMC7366593 DOI: 10.1007/s00436-020-06765-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 06/07/2020] [Indexed: 11/29/2022]
Abstract
AbstractCoccidian parasites possess complex life cycles involving asexual proliferation followed by sexual development leading to the production of oocysts. Coccidian oocysts are persistent stages which are secreted by the feces and transmitted from host to host guaranteeing life cycle progression and disease transmission. The robust bilayered oocyst wall is formed from the contents of two organelles, the wall-forming bodies type I and II (WFBI, WFBII), located exclusively in the macrogametocyte. Eimeria nieschulzi has been used as a model parasite to study and follow gametocyte and oocyst development. In this study, the gametocyte and oocyst wall formation of E. nieschulzi was analyzed by electron microscopy and immuno-histology. A monoclonal antibody raised against the macrogametocytes of E. nieschulzi identified a tyrosine-rich glycoprotein (EnGAM82) located in WFBII. Correlative light and electron microscopy was used to examine the vesicle-specific localization and spatial distribution of GAM82-proteins during macrogametocyte maturation by this monoclonal antibody. In early and mid-stages, the GAM82-protein is ubiquitously distributed in WFBII. Few hours later, the protein is arranged in subvesicular structures. It was possible to show that the substructure of WFBII and the spatial distribution of GAM82-proteins probably represent pre-synthesized cross-linked materials prior to the inner oocyst wall formation. Dityrosine-cross-linked gametocyte proteins can also be confirmed and visualized by fluorescence microscopy (UV light, autofluorescence of WFBII).
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Affiliation(s)
- Stefanie Wiedmer
- Faculty of Biology, Institute of Zoology, Technische Universität Dresden, Zellescher Weg 20 B, 01217, Dresden, Germany.
| | - Thomas Kurth
- Center for Molecular and Cellular Bioengineering (CMCB), Technology Platform, Technische Universität Dresden, Fetscherstraße 105, 01307, Dresden, Germany
| | - Ulrike Buder
- Faculty of Biology, Institute of Zoology, Technische Universität Dresden, Zellescher Weg 20 B, 01217, Dresden, Germany
| | - Sinja Bleischwitz
- Faculty of Biology, Institute of Zoology, Technische Universität Dresden, Zellescher Weg 20 B, 01217, Dresden, Germany
| | - Rolf Entzeroth
- Faculty of Biology, Institute of Zoology, Technische Universität Dresden, Zellescher Weg 20 B, 01217, Dresden, Germany
| | - Michael Kurth
- Faculty of Biology, Institute of Zoology, Technische Universität Dresden, Zellescher Weg 20 B, 01217, Dresden, Germany.
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Wang S, Suo X. Still naïve or primed: Anticoccidial vaccines call for memory. Exp Parasitol 2020; 216:107945. [PMID: 32615133 DOI: 10.1016/j.exppara.2020.107945] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 06/17/2020] [Accepted: 06/22/2020] [Indexed: 01/15/2023]
Abstract
Despite decades of investigation to clarify protective mechanisms of anticoccidial responses, one crucial field is neglected, that is, protective memory responses in primed birds. Protective memory immunity is critical for host resistance to reinfection and is the basis of modern vaccinology, especially in developing successful subunit vaccines. There are important differences between the immune responses induced by infections and antigens delivered either as killed, recombinant proteins or as live, replicating vector vaccines or as DNA vaccines. Animals immunized with these vaccines may fail to develop protective memory immunity, and is still naïve to Eimeria infection. This may explain why limited success is achieved in developing next-generation anticoccidial vaccines. In this review, we try to decipher the protective memory responses against Eimeria infection, assess immune responses elicited by various anticoccidial vaccine candidates, and propose possible approaches to develop rational vaccines that can induce a protective memory response to chicken coccidiosis.
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Affiliation(s)
- Si Wang
- National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing, 100193, China
| | - Xun Suo
- National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China; Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, China Agricultural University, Beijing, 100193, China.
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18
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Immunoprophylactic evaluation of recombinant gametocyte 22 antigen of Eimeria tenella in broiler chickens. Parasitol Res 2019; 118:945-953. [PMID: 30637470 DOI: 10.1007/s00436-018-06198-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 12/28/2018] [Indexed: 12/11/2022]
Abstract
Gametocyte proteins are being explored as potential vaccine candidates against Eimeria sp. in chicken since they are the components of the resilient oocyst wall. The aim of this study was to investigate the immunoprophylactic efficacy of recombinant Eimeria tenella gametocyte antigen 22 (EtGam22) in chickens against homologous oocyst challenge. Broiler chicks were subcutaneously immunized individually with 100 μg of recombinant EtGam22 adjuvanted with Montanide ISA 71 VG at 7 days of age and boosted 2 weeks later. The immunized chickens were challenged individually with 1 × 104 sporulated oocysts of E. tenella 1 week post-booster immunization. The anti-EtGam22 IgY and serum cytokine response was measured post-immunization. The results showed that the anti-EtGam22 IgY antibody, serum IFN-γ, IL-2, TGF-β, and IL-4 levels in chickens vaccinated with recombinant protein were significantly increased post-immunization as compared to unimmunized challenged controls (P < 0.05). The peripheral blood lymphocyte proliferation activity was also found significantly higher in EtGam22-immunized group on day 28, i.e., pre-challenge (P < 0.05). Upon homologous oocyst challenge, chickens immunized with rEtGam22 exhibited a significant drop in the total oocyst output per bird (246.78 ± 36.9 × 106, 45.23% reduction) and a significantly higher weight gain (497.7 ± 19.2 g) as compared to unimmunized challenged controls. Taken together, these data indicate that EtGam22 is a potent immunogen for use as a subunit vaccine against cecal coccidiosis in chickens as it induces a diverse and robust immune response involving multiple cytokines and strong antibody titers.
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Liu T, Huang J, Li Y, Ehsan M, Wang S, Zhou Z, Song X, Yan R, Xu L, Li X. Molecular characterisation and the protective immunity evaluation of Eimeria maxima surface antigen gene. Parasit Vectors 2018; 11:325. [PMID: 29848353 PMCID: PMC5977735 DOI: 10.1186/s13071-018-2906-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/20/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Coccidiosis is recognised as a major parasitic disease in chickens. Eimeria maxima is considered as a highly immunoprotective species within the Eimeria spp. family that infects chickens. In the present research, the surface antigen gene of E. maxima (EmSAG) was cloned, and the ability of EmSAG to stimulate protection against E. maxima was evaluated. METHODS Prokaryotic and eukaryotic plasmids expressing EmSAG were constructed. The EmSAG transcription and expression in vivo was performed based on the RT-PCR and immunoblot analysis. The expression of EmSAG in sporozoites and merozoites was detected through immunofluorescence analyses. The immune protection was assessed based on challenge experiments. Flow cytometry assays were used to determine the T cell subpopulations. The serum antibody and cytokine levels were evaluated by ELISA. RESULTS The open reading frame (ORF) of EmSAG gene contained 645 bp encoding 214 amino acid residues. The immunoblot and RT-PCR analyses indicated that the EmSAG gene were transcribed and expressed in vivo. The EmSAG proteins were expressed in sporozoite and merozoite stages of E. maxima by the immunofluorescence assay. Challenge experiments showed that both pVAX1-SAG and the recombinant EmSAG (rEmSAG) proteins were successful in alleviating jejunal lesions, decreasing loss of body weight and the oocyst ratio. Additionally, these experiments possessed anticoccidial indices (ACI) of more than 170. Higher percentages of CD4+ and CD8+ T cells were detected in both EmSAG-inoculated birds than those of the negative control groups (P < 0.05). The EmSAG-specific antibody concentrations of both the rEmSAG and pVAX1-EmSAG groups were much higher than those of the negative controls (P < 0.05). Higher concentrations of IL-4, IFN-γ, TGF-β1 and IL-17 were observed more in both the rEmSAG protein and pVAX1-SAG inoculated groups than those of negative controls (P < 0.05). CONCLUSIONS Our findings suggest that EmSAG is capable of eliciting a moderate immune protection and could be used as an effective vaccine candidate against E. maxima.
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Affiliation(s)
- Tingqi Liu
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Jingwei Huang
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Yanlin Li
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Muhammad Ehsan
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Shuai Wang
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Zhouyang Zhou
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Xiaokai Song
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Ruofeng Yan
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Lixin Xu
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China
| | - Xiangrui Li
- College of Veterinary Medicine, Nanjing Agriculture University, 1 Weigang, Nanjing, Jiangsu, 210095, People's Republic of China.
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Proteomic analysis of protein interactions between Eimeria maxima sporozoites and chicken jejunal epithelial cells by shotgun LC-MS/MS. Parasit Vectors 2018; 11:226. [PMID: 29618377 PMCID: PMC5885459 DOI: 10.1186/s13071-018-2818-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 03/26/2018] [Indexed: 11/12/2022] Open
Abstract
Background Eimeria maxima initiates infection by invading the jejunal epithelial cells of chicken. However, the proteins involved in invasion remain unknown. The research of the molecules that participate in the interactions between E. maxima sporozoites and host target cells will fill a gap in our understanding of the invasion system of this parasitic pathogen. Methods In the present study, chicken jejunal epithelial cells were isolated and cultured in vitro. Western blot was employed to analyze the soluble proteins of E. maxima sporozoites that bound to chicken jejunal epithelial cells. Co-immunoprecipitation (co-IP) assay was used to separate the E. maxima proteins that bound to chicken jejunal epithelial cells. Shotgun LC-MS/MS technique was used for proteomics identification and Gene Ontology was employed for the bioinformatics analysis. Results The results of Western blot analysis showed that four proteins bands from jejunal epithelial cells co-cultured with soluble proteins of E. maxima sporozoites were recognized by the positive sera, with molecular weights of 70, 90, 95 and 130 kDa. The co-IP dilutions were analyzed by shotgun LC-MS/MS. A total of 204 proteins were identified in the E. maxima protein database using the MASCOT search engine. Thirty-five proteins including microneme protein 3 and 7 had more than two unique peptide counts and were annotated using Gene Ontology for molecular function, biological process and cellular localization. The results revealed that of the 35 annotated peptides, 22 (62.86%) were associated with binding activity and 15 (42.86%) were involved in catalytic activity. Conclusions Our findings provide an insight into the interaction between E. maxima and the corresponding host cells and it is important for the understanding of molecular mechanisms underlying E. maxima invasion. Electronic supplementary material The online version of this article (10.1186/s13071-018-2818-4) contains supplementary material, which is available to authorized users.
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Suprihati E, Yunus M. EVALUATION OF THE ANTIGENICITY AND IMMUNOGENICITY OF Eimeria tenella BY REPRODUCTIVE INDEX AND HISTOPATHOLOGICAL CHANGES OF CECAL COCCIDIOSIS VIRULENT LIVE VACCINE IN BROILER CHICKENS. Afr J Infect Dis 2018; 12:104-110. [PMID: 29619439 PMCID: PMC5876782 DOI: 10.2101/ajid.12v1s.15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 10/18/2017] [Accepted: 10/19/2017] [Indexed: 11/11/2022] Open
Abstract
Background: The development of vaccine to control coccidiosis caused by Eimeria tenella (E. tenella) in chickens is intensifying because of the increasing threat of drug resistance to anticoccidial agents. It is important, therefore, to develop a reliable standard method for the assessment of vaccine afficacy particularly antigenicity and immunogenicity become crucial. Evaluation of E. tenella antigenicity and immunogenicity to some low doses can be reflected by reproductive index and histopathological changes. Materials and Methods: The complete random design of research was used in this study. Sixty of two weeks old broilers were divided into four groups and each group composed 15 replications. The group 1 was chicken group without virulent E. tenella oocyst inoculation. The group 2, 3 and group 4 were chicken group inoculated with virulent E. tenella oocyst at doses of 1.0 x 102, 2.0 x 102, 3.0 x 102, respectively. Then all chicken groups were challenged with E. tenella oocyst at doses of 1.0 x 103. Observation of research that represented antigenicity and immunogenicity was clinical sign, reproductive index, histopathological changes. Results: On virulent E. tenella inoculation step, some clinical signs such as appetite, weakness, and diarrhea were very slight on all chicken groups. While on challenge test step, there were no clinical signs of all chicken groups except the group 1. For the reproductive index of virulent E. tenella inoculation step, there were no significantly differences in all chicken groups except the group 1. As reproductive index, the same result pattern was seen for histopathological changes. Conclusion: The low number virulent E. tenella had low reproductive index and few histopathological changes effect that represents a promising strategy to prevent cecal coccidiosis in chickens.
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Affiliation(s)
- Endang Suprihati
- Department of Veterinary Parasitology, Faculty of Veterinary Medicine, Airlangga University, Surabaya, Indonesia
| | - Muchammad Yunus
- Department of Veterinary Parasitology, Faculty of Veterinary Medicine, Airlangga University, Surabaya, Indonesia
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Passive immunization with Eimeria tenella gametocyte antigen 56 (EtGAM56) specific antibodies and active immunization trial with the epitope containing peptide. Vet Parasitol 2017; 247:100-107. [DOI: 10.1016/j.vetpar.2017.09.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 09/12/2017] [Accepted: 09/23/2017] [Indexed: 11/19/2022]
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Sharma N, Singh V, Shyma KP. Role of parasitic vaccines in integrated control of parasitic diseases in livestock. Vet World 2015; 8:590-8. [PMID: 27047140 PMCID: PMC4774718 DOI: 10.14202/vetworld.2015.590-598] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 03/26/2015] [Accepted: 03/31/2015] [Indexed: 11/18/2022] Open
Abstract
Parasitic infections adversely affect animal’s health and threaten profitable animal production, thus affecting the economy of our country. These infections also play a major role in the spread of zoonotic diseases. Parasitic infections cause severe morbidity and mortality in animals especially those affecting the gastrointestinal system and thus affect the economy of livestock owner by decreasing the ability of the farmer to produce economically useful animal products. Due to all these reasons proper control of parasitic infection is critically important for sustained animal production. The most common and regularly used method to control parasitic infection is chemotherapy, which is very effective but has several disadvantages like drug resistance and drug residues. Integrated approaches to control parasitic infections should be formulated including grazing management, biological control, genetic resistance of hosts, and parasitic vaccines. India ranks first in cattle and buffalo population, but the majority of livestock owners have fewer herds, so other measures like grazing management, biological control, genetic resistance of hosts are not much practical to use. The most sustainable and economical approach to control parasitic infection in our country is to vaccinate animals, although vaccines increase the initial cost, but the immunity offered by the vaccine are long lived. Thus, vaccination of animals for various clinical, chronic, subclinical parasitic infections will be a cheaper and effective alternative to control parasitic infection for long time and improve animal production.
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Affiliation(s)
- Neelu Sharma
- Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar - 385 506, Gujarat, India
| | - Veer Singh
- Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar - 385 506, Gujarat, India
| | - K P Shyma
- Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar - 385 506, Gujarat, India
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Abstract
A key part of the life cycle of an organism is reproduction. For a number of important protist parasites that cause human and animal disease, their sexuality has been a topic of debate for many years. Traditionally, protists were considered to be primitive relatives of the ‘higher’ eukaryotes, which may have diverged prior to the evolution of sex and to reproduce by binary fission. More recent views of eukaryotic evolution suggest that sex, and meiosis, evolved early, possibly in the common ancestor of all eukaryotes. However, detecting sex in these parasites is not straightforward. Recent advances, particularly in genome sequencing technology, have allowed new insights into parasite reproduction. Here, we review the evidence on reproduction in parasitic protists. We discuss protist reproduction in the light of parasitic life cycles and routes of transmission among hosts.
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Wunderlich F, Al-Quraishy S, Steinbrenner H, Sies H, Dkhil MA. Towards identifying novel anti-Eimeria agents: trace elements, vitamins, and plant-based natural products. Parasitol Res 2014; 113:3547-56. [PMID: 25185667 DOI: 10.1007/s00436-014-4101-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 08/25/2014] [Indexed: 12/20/2022]
Abstract
Eimeriosis, a widespread infectious disease of livestock, is caused by coccidian protozoans of the genus Eimeria. These obligate intracellular parasites strike the digestive tract of their hosts and give rise to enormous economic losses, particularly in poultry, ruminants including cattle, and rabbit farming. Vaccination, though a rational prophylactic measure, has not yet been as successful as initially thought. Numerous broad-spectrum anti-coccidial drugs are currently in use for treatment and prophylactic control of eimeriosis. However, increasing concerns about parasite resistance, consumer health, and environmental safety of the commercial drugs warrant efforts to search for novel agents with anti-Eimeria activity. This review summarizes current approaches to prevent and treat eimeriosis such as vaccination and commercial drugs, as well as recent attempts to use dietary antioxidants as novel anti-Eimeria agents. In particular, the trace elements selenium and zinc, the vitamins A and E, and natural products extracted from garlic, barberry, pomegranate, sweet wormwood, and other plants are discussed. Several of these novel anti-Eimeria agents exhibit a protective role against oxidative stress that occurs not only in the intestine of Eimeria-infected animals, but also in their non-parasitized tissues, in particular, in the first-pass organ liver. Currently, it appears to be promising to identify safe combinations of low-cost natural products with high anti-Eimeria efficacy for a potential use as feed supplementation in animal farming.
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Affiliation(s)
- Frank Wunderlich
- Department of Biology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
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In vivolocalization of antibodies raised againstEimeria maximawall forming bodies during sexual intracellular development. Parasitology 2014; 141:1726-35. [DOI: 10.1017/s0031182014001012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
SUMMARYApicomplexan parasites cause devastating diseases in humans and livestock. Previously we demonstrated that antibodies targeting transmissible forms of the apicomplexan parasite,Eimeria, are effective at reducing parasite shedding thus preventing the transmission of the disease. However, the mechanisms responsible have not been fully defined. Moreover, there is no direct evidence that the parasite-specific IgG antibodies can reach the parasite developing in the enterocytes of the infected chicken host. This study summarizes our efforts using host immunity, parasite proteomics and 3D microscopy to provide a step forward in our understanding of how this immune response works.Eimeria maximais an important pathogen of poultry and used as a surrogate for a number of human pathogens includingToxoplasmaandPlasmodium. Our studies demonstrate that immunization with the purified wall forming bodies (WFBs) results in a production of parasite-specific IgG antibodies, which have the ability to reachin situgametocytes in the intestinal lumen and permeate the enterocyte/parasite membranes in order to bind to the cytoplasmic Type 1 and Type 2 WFBs. This raises the intriguing possibility that via this process antibodies block the development ofEimeria maxima in vivo.
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Abstract
SUMMARYCoccidiosis, a serious disease resulting from infection with parasitic protozoa of the genusEimeria, causes significant economic losses to the poultry industry, where intensive rearing facilitates transmission of infectious oocysts via the fecal/oral route. Current control relies primarily on prophylactic drugs in feed but, whilst cost effective, the rise of drug resistance and public demands for residue-free meat has encouraged development of alternative control strategies. Chickens that recover from infection withEimeriadevelop solid immunity that is directed against the early asexual stages of the parasite life cycle. This has allowed development of a number of vaccines that utilize deliberate infection with controlled doses of virulent oocysts or reproductively attenuated lines ofEimeria.The latter are immunogenic but non-pathogenic. The realization that both prophylactic drugs and attenuated vaccines control but do not eradicate infection withEimeriaencouraged development of a vaccine based upon maternal immunity. Laying hens exposed toEimeriaare able to transfer protective antibodies to hatchlings via egg yolks and these antibodies have been used to identify parasite proteins that are conserved across the genus. When delivered maternally, these provide an economical means of preventing coccidiosis, offering immediate protection to newly hatched chicks.
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Chapman HD, Barta JR, Blake D, Gruber A, Jenkins M, Smith NC, Suo X, Tomley FM. A selective review of advances in coccidiosis research. ADVANCES IN PARASITOLOGY 2014; 83:93-171. [PMID: 23876872 DOI: 10.1016/b978-0-12-407705-8.00002-1] [Citation(s) in RCA: 164] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Coccidiosis is a widespread and economically significant disease of livestock caused by protozoan parasites of the genus Eimeria. This disease is worldwide in occurrence and costs the animal agricultural industry many millions of dollars to control. In recent years, the modern tools of molecular biology, biochemistry, cell biology and immunology have been used to expand greatly our knowledge of these parasites and the disease they cause. Such studies are essential if we are to develop new means for the control of coccidiosis. In this chapter, selective aspects of the biology of these organisms, with emphasis on recent research in poultry, are reviewed. Topics considered include taxonomy, systematics, genetics, genomics, transcriptomics, proteomics, transfection, oocyst biogenesis, host cell invasion, immunobiology, diagnostics and control.
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Affiliation(s)
- H David Chapman
- Department of Poultry Science, University of Arkansas, Fayetteville, Arkansas, USA.
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Cloning and characterization of an Eimeria necatrix gene encoding a gametocyte protein and associated with oocyst wall formation. Parasit Vectors 2014; 7:27. [PMID: 24428893 PMCID: PMC3896727 DOI: 10.1186/1756-3305-7-27] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 01/02/2014] [Indexed: 11/23/2022] Open
Abstract
Background Gametocyte proteins of Eimeria (E.) spp. are important components of the oocyst wall and some have been used to develop transmission-blocking vaccines against avian coccidiosis. Methods Total RNA isolated from E. necatrix gametocytes was utilized as templates for RT-PCR amplification and sequencing of cDNA encoding a gametocyte protein using gene-specific primers. The cDNA was cloned into the bacterial expression vector pET28a(+) and expressed in E. coli BL21 cells. The antigenicity of the recombinant gametocyte protein and its localization in different E. necatrix life-cycle stages were determined by western blot and indirect immunofluorescence analyses, respectively. Results A 731-nucleotide sequence of cDNA [GenBank: KF649255] of E. necatrix had 97.7% identity to that of Etgam22 of E. tenella. The cDNA ORF encoded a 186-amino acid protein containing a histidine-proline-rich region. The recombinant gametocyte protein (rEnGAM22) was predominately expressed in the insoluble inclusion body and recognized by antiserum from chickens immunized with oocysts of E. necatrix, E. maxima and E. tenella. A specific antibody to the rEnGAM22 protein recognized the wall-forming bodies in macrogametocytes and the walls of oocysts and sporocysts. Conclusions The gene cloned from E. necatrix gametocytes is an ortholog to Etgam22 of E. tenella and presents a potential target for future recombinant subunit vaccines against coccidiosis.
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Dalloul RA, Lillehoj HS. Poultry coccidiosis: recent advancements in control measures and vaccine development. Expert Rev Vaccines 2014; 5:143-63. [PMID: 16451116 DOI: 10.1586/14760584.5.1.143] [Citation(s) in RCA: 362] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Coccidiosis is recognized as the major parasitic disease of poultry and is caused by the apicomplexan protozoan Eimeria. Coccidiosis seriously impairs the growth and feed utilization of infected animals resulting in loss of productivity. Conventional disease control strategies rely heavily on chemoprophylaxis and, to a certain extent, live vaccines. Combined, these factors inflict tremendous economic losses to the world poultry industry in excess of USD 3 billion annually. Increasing regulations and bans on the use of anticoccidial drugs coupled with the associated costs in developing new drugs and live vaccines increases the need for the development of novel approaches and alternative control strategies for coccidiosis. This paper aims to review the current progress in understanding the host immune response to Eimeria and discuss current and potential strategies being developed for coccidiosis control in poultry.
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Affiliation(s)
- Rami A Dalloul
- Animal & Natural Resources Institute, BARC-East, Animal Parasitic Diseases Laboratory, USDA-ARS, Beltsville, MD 20705, USA.
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32
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Securing poultry production from the ever-present Eimeria challenge. Trends Parasitol 2014; 30:12-9. [DOI: 10.1016/j.pt.2013.10.003] [Citation(s) in RCA: 245] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/02/2013] [Accepted: 10/06/2013] [Indexed: 01/16/2023]
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Abstract
SUMMARYEimeriais a common genus of apicomplexan parasites that infect diverse vertebrates, most notably poultry, causing serious disease and economic loss. Like all apicomplexans, eimerians have a complex life cycle characterized by asexual divisions that amplify the parasite population in preparation for sexual reproduction. This can be divided into three events: gametocytogenesis, producing gametocytes from merozoites; gametogenesis, producing microgametes and macrogametes from gametocytes; and fertilization of macrogametes by microgametes, producing diploid zygotes with ensuing meiosis completing the sexual phase. Sexual development inEimeriadepends on the differential expression of stage-specific genes, rather than presence or absence of sex chromosomes. Thus, it involves the generation of specific structures and, implicitly, storage of proteins and regulation of protein expression in macrogametes, in preparation for fertilization. InEimeria, the formation of a unique, resilient structure, the oocyst wall, is essential for completion of the sexual phase and parasite transmission. In this review, we piece together the molecular events that underpin sexual reproduction inEimeriaand use additional details from analogous events inPlasmodiumto fill current knowledge gaps. The mechanisms governing sexual stage formation and subsequent fertilization may represent targets for counteracting parasite transmission.
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DING J, LIU QR, HAN JP, QIAN WF, LIU Q. Anti-Recombinant Gametocyte 56 Protein IgY Protected Chickens from Homologous Coccidian Infection. JOURNAL OF INTEGRATIVE AGRICULTURE : JIA 2012; 11:1721-1728. [PMID: 32288948 PMCID: PMC7128897 DOI: 10.1016/s2095-3119(12)60176-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 09/05/2011] [Indexed: 06/11/2023]
Abstract
Coccidiosis is caused by intra-cellular infection of Eimeria spp., which goes through a complex life cycle in the intestinal mucosa of infected hosts. Specific immunoglobulins (IgY) could be produced in egg yolk by immunizing hens with specific antigens. In the present study, we cloned the E. maxima gam56 gene, expressed the GST-GAM56 fusion protein and raised IgY to GST-GAM56 in hens. The anti-GST-GAM56 IgY antibody was isolated and used to treat chickens infected with E. maxima oocysts. Intramuscular injection of the antibodies provided minimal protection against parasite infection. However, oral dosing of the IgY 3 or 5 d after oocyst inoculation significantly improved body weight gain, reduced oocyst output and intestinal lesion score were reduced at 3 or 5 d after oocyst challenging, compared to the untreated control group. Our findings suggest that the IgY to gam56 could be an effective prophylactic or therapeutic agent against E. maxima infection in chickens and should have a practical application value.
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Affiliation(s)
| | | | | | | | - Qun LIU
- Correspondence LIU Qun, Tel: +86-10-62734496
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35
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Shirley MW, Lillehoj HS. The long view: a selective review of 40 years of coccidiosis research. Avian Pathol 2012; 41:111-21. [PMID: 22515530 DOI: 10.1080/03079457.2012.666338] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This selective review of 40 years of coccidiosis research is one of a number on important diseases of poultry to celebrate the 40th anniversary of the birth of Avian Pathology, the journal of the World Veterinary Poultry Association, and is written for the non-specialist. The intention is to provide a flavour of the field problems and intellectual challenges, with emphasis in the areas of immunology and vaccinology that drove research in the 1970s, and to reflect on research progress since.
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Affiliation(s)
- M W Shirley
- Animal Parasitic Diseases Laboratory, USDA – Agricultural Research Service, Beltsville, MD, 20705, USA.
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36
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Peek H, Landman W. Coccidiosis in poultry: anticoccidial products, vaccines and other prevention strategies. Vet Q 2011; 31:143-61. [DOI: 10.1080/01652176.2011.605247] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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37
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Comparison of protective immune responses to apicomplexan parasites. J Parasitol Res 2011; 2012:852591. [PMID: 21876783 PMCID: PMC3159010 DOI: 10.1155/2012/852591] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 06/27/2011] [Indexed: 12/02/2022] Open
Abstract
Members of the phylum Apicomplexa, which includes the species Plasmodium, Eimeria, Toxoplasma, and Babesia amongst others, are the most successful intracellular pathogens known to humankind. The widespread acquisition of antimicrobial resistance to most drugs used to date has sparked a great deal of research and commercial interest in the development of vaccines as alternative control strategies. A few antigens from the asexual and sexual stages of apicomplexan development have been identified and their genes characterised; however, the fine cellular and molecular details of the effector mechanisms crucial for parasite inhibition and stimulation of protective immunity are still not entirely understood. This paper provides an overview of what is currently known about the protective immune response against the various types of apicomplexan parasites and focuses mainly on the similarities of these pathogens and their host interaction. Finally, the evolutionary relationships of these parasites and their hosts, as well as the modulation of immune functions that are critical in determining the outcome of the infection by these pathogenic organisms, are discussed.
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38
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Cross-protection of chicken immunoglobulin Y antibodies against H5N1 and H1N1 viruses passively administered in mice. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2011; 18:1083-90. [PMID: 21613458 DOI: 10.1128/cvi.05075-11] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Influenza viruses remain a major threat to global health due to their ability to undergo change through antigenic drift and antigenic shift. We postulated that avian IgY antibodies represent a low-cost, effective, and well-tolerated approach that can easily be scaled up to produce enormous quantities of protective antibodies. These IgY antibodies can be administered passively in humans (orally and intranasally) and can be used quickly and safely to help in the fight against an influenza pandemic. In this study, we raised IgY antibodies against H1N1, H3N2, and H5N1 influenza viruses. We demonstrated that, using whole inactivated viruses alone and in combination to immunize hens, we were able to induce a high level of anti-influenza virus IgY in the sera and eggs, which lasted for at least 2 months after two immunizations. Furthermore, we found that by use of in vitro assays to test for the ability of IgY to inhibit hemagglutination (HI test) and virus infectivity (serum neutralization test), IgYs inhibited the homologous as well as in some cases heterologous clades and strains of viruses. Using an in vivo mouse model system, we found that, when administered intranasally 1 h prior to infection, IgY to H5N1 protected 100% of the mice against lethal challenge with H5N1. Of particular interest was the finding that IgY to H5N1 cross-protected against A/Puerto Rico/8/34 (H1N1) both in vitro and in vivo. Based on our results, we conclude that anti-influenza virus IgY can be used to help prevent influenza virus infection.
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del Cacho E, Gallego M, Francesch M, Quílez J, Sánchez-Acedo C. Effect of artemisinin on oocyst wall formation and sporulation during Eimeria tenella infection. Parasitol Int 2010; 59:506-11. [DOI: 10.1016/j.parint.2010.04.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 02/21/2010] [Accepted: 04/12/2010] [Indexed: 11/28/2022]
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40
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Yim D, Kang SS, Kim DW, Kim SH, Lillehoj HS, Min W. Protective effects of Aloe vera-based diets in Eimeria maxima-infected broiler chickens. Exp Parasitol 2010; 127:322-5. [PMID: 20723543 DOI: 10.1016/j.exppara.2010.08.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 07/02/2010] [Accepted: 08/11/2010] [Indexed: 11/28/2022]
Abstract
Aloes have been widely used for a broad range of pharmacological activities, including parasitic problems. Avian coccidiosis is the most costly and wide-spread parasitic disease in the poultry industry, and has been mainly controlled by the use of chemotherapeutic agents. Due to the emergence of drug-resistant strains, alternative control strategies are needed. In this study, the protective effects of Aloe vera-based diets were assessed in broiler chickens following oral infection with Eimeria maxima. Chickens were fed a regular diet supplemented with ground Aloe vera throughout the duration of the experiment beginning 2 days prior to infection with 1 × 10(4) sporulated oocysts of E. maxima. No significant differences were found in body weight gain or loss between the Aloe vera-supplemented and unsupplemented groups with or without E. maxima infections. Fecal oocyst shedding decreased significantly (p < 0.05) in all of the treatment groups that were supplemented with Aloe vera as compared to the unsupplemented group. Furthermore, the Aloe vera-supplemented group showed significantly fewer intestinal lesions (p < 0.05) than the unsupplemented group following infection. The findings of this study suggest that Aloe vera could be used an alternative treatment for controlling avian coccidiosis.
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Affiliation(s)
- Dongjean Yim
- College of Veterinary Medicine & Research Institute of Life Science, Gyeongsang National University, Jinju 660-701, Republic of Korea
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41
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Schnitzler BE, Shirley MW. Immunological aspects of infections withEimeria maxima: A short review. Avian Pathol 2010; 28:537-543. [DOI: 10.1080/03079459994326] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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42
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Wallach M. Role of antibody in immunity and control of chicken coccidiosis. Trends Parasitol 2010; 26:382-7. [PMID: 20452286 DOI: 10.1016/j.pt.2010.04.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 04/09/2010] [Accepted: 04/12/2010] [Indexed: 01/20/2023]
Abstract
Research has been carried out worldwide to try to elucidate the mechanism of protective immunity against coccidiosis. It was concluded from early studies that cellular immunity is the key to protection against Eimeria, whereas humoral immunity plays a very minor role in resistance against infection. By contrast, other studies have pointed towards the ability of antibody to block parasite invasion, development and transmission and to provide passive and maternal immunity against challenge infection. Herein, recent results demonstrate the ability of antibodies (raised by live immunization or against purified stage-specific Eimeria antigens) to inhibit parasite development in vitro and in vivo and readdress the question of the role of antibody in protection against coccidiosis.
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Affiliation(s)
- Michael Wallach
- Institute for the Biotechnology of Infectious Diseases, University of Technology Sydney, PO Box 123, Broadway, Sydney, New South Wales, 2007, Australia.
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43
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Effect of Dietary Curcuma, Capsicum, and Lentinus, on Enhancing Local Immunity against Eimeria acervulina Infection. J Poult Sci 2010. [DOI: 10.2141/jpsa.009025] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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44
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Belli SI, Ferguson DJ, Katrib M, Slapetova I, Mai K, Slapeta J, Flowers SA, Miska KB, Tomley FM, Shirley MW, Wallach MG, Smith NC. Conservation of proteins involved in oocyst wall formation in Eimeria maxima, Eimeria tenella and Eimeria acervulina. Int J Parasitol 2009; 39:1063-70. [PMID: 19477178 PMCID: PMC2726925 DOI: 10.1016/j.ijpara.2009.05.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 05/18/2009] [Accepted: 05/18/2009] [Indexed: 11/25/2022]
Abstract
Vaccination with proteins from gametocytes of Eimeria maxima protects chickens, via transfer of maternal antibodies, against infection with several species of Eimeria. Antibodies to E. maxima gametocyte proteins recognise proteins in the wall forming bodies of macrogametocytes and oocyst walls of E. maxima, Eimeria tenella and Eimeria acervulina. Homologous genes for two major gametocyte proteins - GAM56 and GAM82 - were found in E. maxima, E. tenella and E. acervulina. Alignment of the predicted protein sequences of these genes reveals that, as well as sharing regions of tyrosine richness, strong homology exists in their amino-terminal regions, where protective antibodies bind. This study confirms the conservation of the roles of GAM56 and GAM82 in oocyst wall formation and shows that antibodies to gametocyte antigens of E. maxima cross-react with homologous proteins in other species, helping to explain cross-species maternal immunity.
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Affiliation(s)
- Sabina I. Belli
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
| | - David J.P. Ferguson
- Nuffield Department of Pathology, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Marilyn Katrib
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
| | - Iveta Slapetova
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
| | - Kelly Mai
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
| | - Jan Slapeta
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
| | - Sarah A. Flowers
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
| | - Kate B. Miska
- United States Department of Agriculture, Agricultural Research Service, Animal Parasitic Diseases Laboratory, Beltsville, MD 20705, USA
| | - Fiona M. Tomley
- Institute for Animal Health, Compton, Newbury, Berkshire RG20 7NN, UK
| | - Martin W. Shirley
- Institute for Animal Health, Compton, Newbury, Berkshire RG20 7NN, UK
| | - Michael G. Wallach
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
| | - Nicholas C. Smith
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, NSW 2007, Australia
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45
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Protective effect of hyperimmune egg yolk IgY antibodies against Eimeria tenella and Eimeria maxima infections. Vet Parasitol 2009; 163:123-6. [DOI: 10.1016/j.vetpar.2009.04.020] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 03/20/2009] [Accepted: 04/08/2009] [Indexed: 11/22/2022]
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46
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Reichel MP, Ellis JT. Neospora caninum--how close are we to development of an efficacious vaccine that prevents abortion in cattle? Int J Parasitol 2009; 39:1173-87. [PMID: 19497326 DOI: 10.1016/j.ijpara.2009.05.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Revised: 05/19/2009] [Accepted: 05/20/2009] [Indexed: 10/20/2022]
Abstract
Neospora caninum is a protozoan parasite that causes abortion in cattle around the world. Although the clinical signs of disease in both dogs and cattle have now been recognised for over 20years, treatment and control options are still limited, despite the availability of a commercial vaccine in some countries of the world. The case for an efficacious vaccine has not been convincingly waged by farmers, veterinarians and other members of the agricultural and rural communities. In recent times, however, economic modelling has been used to estimate the industry losses due to Neospora-associated abortion, providing, in turn, the business case for forms of control for this parasite, including the development of vaccines. In this review, we document progress in all areas of the vaccine development pipeline, including live, killed and recombinant forms and the animal models available for vaccine evaluation. In addition, we summarise the main outcomes on the economics of Neospora control and suggest that the current boom in the global dairy industry increases the specific need for a vaccine against N. caninum-associated abortion.
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Affiliation(s)
- Michael P Reichel
- Department of Medical and Molecular Biosciences, University of Technology, Sydney, P.O. Box 123, Broadway, NSW 2007, Australia
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Lee S, Lillehoj H, Park D, Jang S, Morales A, García D, Lucio E, Larios R, Victoria G, Marrufo D, Lillehoj E. Induction of passive immunity in broiler chickens against Eimeria acervulina by hyperimmune egg yolk immunoglobulin Y. Poult Sci 2009; 88:562-6. [DOI: 10.3382/ps.2008-00340] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Wallach MG, Ashash U, Michael A, Smith NC. Field application of a subunit vaccine against an enteric protozoan disease. PLoS One 2008; 3:e3948. [PMID: 19079606 PMCID: PMC2596963 DOI: 10.1371/journal.pone.0003948] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Accepted: 11/08/2008] [Indexed: 11/19/2022] Open
Abstract
Background Coccidiosis is a major global veterinary health problem in intensively reared chickens. It is caused by apicomplexan parasites of the genus Eimeria. Principal Findings A subunit vaccine composed of purified antigens from the gametocytes of Eimeria maxima was used to stimulate the production and transfer of maternal antibodies between breeding hens and their hatchlings. The vaccine was injected into hens twice before they began laying eggs. Immunization had no adverse affects on egg laying or health of the hens and resulted in high antibody levels throughout the life of the hens. Progeny of immunized hens excreted significantly less oocysts of various species of Eimeria in their faeces than chicks from unvaccinated hens. Furthermore, the offspring of vaccinated hens developed stronger natural immunity to Eimeria, so that they were resistant to challenge infection even at 8 weeks of age, well after all maternal antibodies had left their circulation. Field trials were conducted in South Africa, Brazil and Thailand, involving at least 1 million progeny of vaccinated hens and at least 1 million positive control birds (raised on feed containing anticoccidial drugs or immunized with a live vaccine) in each country. Additionally, trials were carried out in Israel involving 60 million progeny of vaccinated hens and 112 million positive control birds. There were no significant differences in growth rate, feed conversion ratios or mortality in the offspring of vaccinated hens compared with the positive control chickens in any of these countries regardless of different management practices, different breeds of chickens or climate. Conclusions These results demonstrate that a vaccine composed of antigens purified from the gametocytes of Eimeria can be used safely and effectively to prevent the deleterious effects of coccidiosis. It is the first subunit vaccine against any protozoan parasite to be successfully applied on a commercial scale.
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Affiliation(s)
- Michael G Wallach
- Institute for the Biotechnology of Infectious Diseases, University of Technology Sydney, Broadway, Australia.
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Ding J, Bao W, Liu Q, Yu Q, Abdille MH, Wei Z. Immunoprotection of chickens against Eimeria acervulina by recombinant α-tubulin protein. Parasitol Res 2008; 103:1133-40. [DOI: 10.1007/s00436-008-1106-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Accepted: 06/19/2008] [Indexed: 12/01/2022]
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MORN1 has a conserved role in asexual and sexual development across the apicomplexa. EUKARYOTIC CELL 2008; 7:698-711. [PMID: 18310354 DOI: 10.1128/ec.00021-08] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The gene encoding the membrane occupation and recognition nexus protein MORN1 is conserved across the Apicomplexa. In Toxoplasma gondii, MORN1 is associated with the spindle poles, the anterior and posterior rings of the inner membrane complex (IMC). The present study examines the localization of MORN1 during the coccidian development of T. gondii and three Eimeria species (in the definitive host) and erythrocytic schizogony of Plasmodium falciparum. During asexual proliferation, MORN1 is associated with the posterior ring of the IMCs of the multiple daughters forming during T. gondii endopolygeny and schizogony in Eimeria and P. falciparum. Furthermore, the expression of P. falciparum MORN1 protein peaked in late schizogony. These data fit a model with a conserved role for MORN1 during IMC assembly in all variations of asexual development. An important new observation is the reactivity of MORN1 antibody with certain sexual stages in T. gondii and Eimeria species. Here MORN1 is organized as a ring-like structure where the microgametes bud from the microgametocyte while in mature microgametes it is present near the flagellar basal bodies and mitochondrion. These observations suggest a conserved role for MORN1 in both asexual and sexual development across the Apicomplexa.
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