1
|
Kang HJ, Mao J, Kim MJ, Yoon KW, Eom GD, Chu KB, Moon EK, Quan FS. The detection of Toxoplasma gondii ME49 infections in BALB/c mice using various techniques. PARASITES, HOSTS AND DISEASES 2023; 61:418-427. [PMID: 38043537 PMCID: PMC10693974 DOI: 10.3347/phd.23048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 08/23/2023] [Indexed: 12/05/2023]
Abstract
Toxoplasma gondii infections are primarily diagnosed by serological assays, whereas molecular and fluorescence-based techniques are garnering attention for their high sensitivity in detecting these infections. Nevertheless, each detection method has its limitations. The toxoplasmosis detection capabilities of most of the currently available methods have not been evaluated under identical experimental conditions. This study aimed to assess the diagnostic potential of enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (RT-PCR), immunohistochemistry (IHC), and immunofluorescence (IF) in BALB/c mice experimentally infected with various doses of T. gondii ME49. The detection of toxoplasmosis from sera and brain tissues was markedly enhanced in mice subjected to high infection doses (200 and 300 cysts) compared to those subjected to lower doses (10 and 50 cysts) for all the detection methods. Additionally, increased B1 gene expression levels and cyst sizes were observed in the brain tissues of the mice. Importantly, IHC, IF, and ELISA, but not RT-PCR, successfully detected T. gondii infections at the lowest infection dose (10 cysts) in the brain. These findings may prove beneficial while designing experimental methodologies for detecting T. gondii infections in mice.
Collapse
Affiliation(s)
- Hae-Ji Kang
- Center for Translational Antiviral Research, Georgia State University Institute for Biomedical Sciences, Atlanta, GA 30303,
USA
| | - Jie Mao
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Min-Ju Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Keon-Woong Yoon
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Gi-Deok Eom
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Ki-Back Chu
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447,
Korea
| | - Eun-Kyung Moon
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447,
Korea
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447,
Korea
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447,
Korea
| |
Collapse
|
2
|
Madlala T, Adeleke VT, Okpeku M, Tshilwane SI, Adeniyi AA, Adeleke MA. Screening of apical membrane antigen-1 (AMA1), dense granule protein-7 (GRA7) and rhoptry protein-16 (ROP16) antigens for a potential vaccine candidate against Toxoplasma gondii for chickens. Vaccine X 2023; 14:100347. [PMID: 37519774 PMCID: PMC10384181 DOI: 10.1016/j.jvacx.2023.100347] [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: 07/23/2022] [Revised: 06/23/2023] [Accepted: 07/06/2023] [Indexed: 08/01/2023] Open
Abstract
Toxoplasmosis is a zoonotic disease caused by the protozoan parasite, Toxoplasma gondii known to infect almost all animals, including birds and humans globally. This disease has impacted the livestock industry and public health, where infection of domestic animals increases the zoonotic risk of transmission of infection to humans, threatening public health. Hence the need to discover novel and safe vaccines to fight against toxoplasmosis. In the current study, a novel multiepitope vaccine was designed using immunoinformatics techniques targeting T. gondii AMA1, GRA7 and ROP16 antigens, consisting of antigenic, immunogenic, non-allergenic and cytokine inducing T-cell (9 CD8+ and 15 CD4+) epitopes and four (4) B-cell epitopes fused together using AAY, KK and GPGPG linkers. The tertiary model of the proposed vaccine was predicted and validated to confirm the structural quality of the vaccine. The designed vaccine was highly antigenic (antigenicity = 0.6645), immunogenic (score = 2.89998), with molecular weight of 73.35 kDa, instability and aliphatic index of 28.70 and 64.10, respectively; and GRAVY of -0.363. The binding interaction, stability and flexibility were assessed with molecular docking and dynamics simulation, which revealed the proposed vaccine to have good structural interaction (binding affinity = -106.882 kcal/mol) and stability when docked with Toll like receptor-4 (TLR4). The results revealed that the Profilin-adjuvanted vaccine is promising, as it predicted induction of enhanced immune responses through the production of cytokines and antibodies critical in blocking host invasion.
Collapse
Affiliation(s)
- Thabile Madlala
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, P/Bag X54001, Durban 4000, South Africa
| | - Victoria T. Adeleke
- Department of Chemical Engineering, Mangosuthu University of Technology, Durban 4031, South Africa
| | - Moses Okpeku
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, P/Bag X54001, Durban 4000, South Africa
| | - Selaelo I. Tshilwane
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa
| | - Adebayo A. Adeniyi
- Department of Industrial Chemistry, Federal University, Oye-Ekiti, P.O Box 370111, Nigeria
- Department of Chemistry, Faculty of Natural and Agricultural Sciences, University of the Free State, Bloemfontein, South Africa
| | - Matthew A. Adeleke
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Westville, P/Bag X54001, Durban 4000, South Africa
| |
Collapse
|
3
|
Alijani M, Saffar B, Yosefi Darani H, Mahzounieh M, Fasihi-Ramandi M, Shakshi-Niaei M, Soltani S, Ghaemi A, Shirian S. Immunological evaluation of a novel multi-antigenic DNA vaccine encoding SAG1, SAG3, MIC4, GRA5, GRA7, AMA1and BAG1 against Toxoplasma gondii in BALB/c mice. Exp Parasitol 2023; 244:108409. [PMID: 36403800 DOI: 10.1016/j.exppara.2022.108409] [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: 06/21/2021] [Revised: 09/25/2022] [Accepted: 10/18/2022] [Indexed: 11/20/2022]
Abstract
Many recent studies have been conducted to find new DNA vaccines based on Toxoplasma gondii antigens. DNA vaccines encoding complex of different antigens showed better immune responses compared to single antigen vaccine. In this study, we constructed a DNA vaccine encoding SAG1, SAG3, MIC4, GRA5, GRA7, AMA1 and BAG1 against T. gondii, and evaluated the immune response it induced in BALB/c mice. For this purposes, thirty BALB/c mice were randomly divided into three groups containing tenmice each. There were two negative control groups (PBSand pVAX1 vector) and one vaccination group (pVAX1-MAF, Multantigenic Fragment). On days 0, 14 and 28, the mice were immunized intramuscularly, and 5 weeks later they were challenged with T. gondii RH strain. The immune responses were evaluated using lymphocyte proliferation assay, T-cell subsets detection, and measurement of antibody and cytokine levels. The results showed that mice immunized with pVAX1-MAF developed high levels of IL-2, IL-12, IgG and IFN- γ as well as CD3+CD4+ T cells. In addition, the survival time of mice immunized by pVAX1-MAF was longer than that control mice. In conclusion, our results show that the multiple DNA vaccine encodingSAG1, SAG3, mic4, GRA5, GRA7, AMA and BAG1effectively enhanced humoral and cellular immune responses, and prolonged the survival time. Together this would suggest that further investigation may result in a promising candidate vaccine to treat toxoplasmosis.
Collapse
Affiliation(s)
- Mohammadreza Alijani
- Graduated Student of Veterinary Medicine, Shahrekord University, Shahrekord, Iran; Shiraz Molecular Pathology Research Center, Dr Daneshbod Path Lab, Shiraz, Iran
| | - Behnaz Saffar
- Department of Genetics, Faculty of Basic Sciences, Shahrekord University, Shahrekord, Iran
| | - Hossein Yosefi Darani
- Department of Parasitology, Faculty of Medicine, Esfahan University of Medical Science, Esfahan, Iran
| | - Mohammadreza Mahzounieh
- Department of Pathobiology, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran.
| | - Mahdi Fasihi-Ramandi
- Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Mostafa Shakshi-Niaei
- Department of Genetics, Faculty of Basic Sciences, Shahrekord University, Shahrekord, Iran
| | - Sodabe Soltani
- Graduated Student of Genetics, Shahrekord University, Shahrekord, Iran
| | - Amir Ghaemi
- Department of Virology, Pasteur Institute of Iran, Tehran, Iran
| | - Sadegh Shirian
- Department of Pathology, School of Veterinary Pathology, Shahrekord University, Shahrekord, Iran; Shefa Neuroscience Research Center, Kahatm Al-Anbia Hospital, Tehran, Iran.
| |
Collapse
|
4
|
Mamaghani AJ, Fathollahi A, Arab-Mazar Z, kohansal K, Fathollahi M, Spotin A, Bashiri H, Bozorgomid A. Toxoplasma gondii vaccine candidates: a concise review. Ir J Med Sci 2023; 192:231-261. [PMID: 35394635 PMCID: PMC8992420 DOI: 10.1007/s11845-022-02998-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 03/16/2022] [Indexed: 02/08/2023]
Abstract
Toxoplasma gondii is an obligate intracellular parasite that causes toxoplasmosis. It has been shown that the severity of symptoms depends on the functioning of the host immune system. Although T. gondii infection typically does not lead to severe disease in healthy people and after infection, it induces a stable immunity, but it can contribute to severe and even lethal Toxoplasmosis in immunocompromised individuals (AIDS, bone marrow transplant and neoplasia). The antigens that have been proposed to be used in vaccine candidate in various studies include surface antigens and secretory excretions that have been synthesized and evaluated in different studies. In some studies, secretory antigens play an important role in stimulating the host immune response. Various antigens such as SAG, GRA, ROP, ROM, and MAG have been from different strains of T. gondii have been synthesized and their protective effects have been evaluated in animal models in different vaccine platforms including recombinant antigens, nanoparticles, and DNA vaccine. Four bibliographic databases including Science Direct, PubMed Central (PMC), Scopus, and Google Scholar were searched for articles published up to 2020.The current review article focuses on recent studies on the use and usefulness of recombinant antigens, nanoparticles, and DNA vaccines.
Collapse
Affiliation(s)
- Amirreza Javadi Mamaghani
- Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Anwar Fathollahi
- Department of Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Zahra Arab-Mazar
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Kobra kohansal
- Department of Medical Parasitology, School of Medicine, Jondishapour University of Medical Sciences, Ahvaz, Iran
| | - Matin Fathollahi
- Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Adel Spotin
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Homayoon Bashiri
- Infectious Diseases Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Arezoo Bozorgomid
- Infectious Diseases Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| |
Collapse
|
5
|
Recombinant AMA1 Virus-like Particle Antigen for Serodiagnosis of Toxoplasma gondii Infection. Biomedicines 2022; 10:biomedicines10112812. [PMID: 36359332 PMCID: PMC9687185 DOI: 10.3390/biomedicines10112812] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/27/2022] [Accepted: 10/30/2022] [Indexed: 11/06/2022] Open
Abstract
Toxoplasmosis diagnosis predominantly relies on serology testing via enzyme-linked immunosorbent assay (ELISA), but these results are highly variable. Consequently, various antigens are being evaluated to improve the sensitivity and specificity of toxoplasmosis serological diagnosis. Here, we generated Toxoplasma gondii virus-like particles displaying AMA1 of T. gondii and evaluated their diagnostic potential. We found that AMA1 VLPs were highly sensitive and reacted with the sera acquired from mice infected with either T. gondii ME49 or RH strains. The overall IgG and IgM antibody responses elicited by AMA1 VLPs were substantially higher than those induced by the conventionally used T. gondii lysate antigen (TLA). Importantly, AMA1 VLPs were capable of detecting parasitic infection with T. gondii RH and ME49 as early as 1 week post-infection, even when mice were exposed to low infectious doses (5 × 103 and 10 cysts, respectively). AMA1 VLPs also did not cross-react with the immune sera acquired from Plasmodium berghei-infected mice. Compared to TLA, stronger antibody responses were induced by AMA1 VLPs when tested using T. gondii-infected human sera. The sensitivities and specificities of the two antigens were substantially different, with AMA1 VLPs demonstrating over 90% sensitivity and specificity, whereas these values were in the 70% range for the TLA. These results indicated that AMA1 VLPs can detect infections of both T. gondii ME49 and RH at an early stage of infection caused by very low infection doses in mice, and these could be used for serological diagnosis of human toxoplasmosis.
Collapse
|
6
|
Kim MJ, Mao J, Kang HJ, Chu KB, Quan FS. Detection of Toxoplasma gondii Infections using Virus-Like Particles Displaying T. gondii ROP4 Antigen. THE KOREAN JOURNAL OF PARASITOLOGY 2021; 59:565-572. [PMID: 34974663 PMCID: PMC8721301 DOI: 10.3347/kjp.2021.59.6.565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/08/2021] [Accepted: 12/08/2021] [Indexed: 11/27/2022]
Abstract
Toxoplasma gondii ME49 infections are typically diagnosed by serological tests. However, serological diagnosis of RH strain-induced toxoplasmosis remains unknown. In order to develop seradiagnosis of above 2 kinds of infections, we generated recombinant virus-like particles (VLPs) displaying the T. gondii rhoptry protein 4 (ROP4) and evaluated their potential in T. gondii ME49 or RH strain infection diagnostics. Mice were orally infected with either the tachyzoites of T. gondii (RH) or cysts of T. gondii (ME49) at various dosages, and sera were collected at regular intervals. ELISA-based serological tests were performed to assess IgG, IgM, and IgA antibody responses against ROP4 VLP antigen and tissue lysate antigen (TLA). Compared to TLA, IgG, IgM, and IgA levels to ROP4 VLP antigen were significantly higher in the sera of T. gondii RH-infected mice 1 and 2 week post-infection (PI). T. gondii-specific IgG antibody was detected at 1, 2, 4, and 8 week PI in the T. gondii ME49-infected mice with infection dose-dependent manner. These results indicated that the ROP4 VLP antigen was highly sensitive antigens detecting T. gondii RH and ME49 antibodies at an early stage.
Collapse
Affiliation(s)
- Min-Ju Kim
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Jie Mao
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Hae-Ji Kang
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Ki-Back Chu
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447,
Korea
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447,
Korea
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul 02447,
Korea
| |
Collapse
|
7
|
Virus-Like Particle Vaccines Against Respiratory Viruses and Protozoan Parasites. Curr Top Microbiol Immunol 2021; 433:77-106. [PMID: 33650036 DOI: 10.1007/82_2021_232] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The field of vaccinology underwent massive advances over the past decades with the introduction of virus-like particles (VLPs), a supra-molecular nanoparticle vaccine platform that resembles viral structures without the ability to replicate in hosts. This innovative approach has been remarkably effective, as evidenced by its profound immunogenicity and safety. These highly desirable intrinsic properties enabled their further development as vaccines against a multitude of diseases. To date, several VLP-based vaccines have already been commercialized and many more are undergoing clinical evaluation prior to FDA approval. However, efficacious vaccines against a plethora of pathogens are still lacking, which imposes a tremendous socioeconomic burden and continues to threaten public health throughout the globe. This is especially the case for several respiratory pathogens and protozoan parasites. In this review, we briefly describe the fundamentals of VLP vaccines and the unique properties that enable these to be such valuable vaccine candidates and summarize current advances in VLP-based vaccines targeting respiratory and parasitic diseases of global importance.
Collapse
|
8
|
Chu KB, Quan FS. Advances in Toxoplasma gondii Vaccines: Current Strategies and Challenges for Vaccine Development. Vaccines (Basel) 2021; 9:vaccines9050413. [PMID: 33919060 PMCID: PMC8143161 DOI: 10.3390/vaccines9050413] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 02/06/2023] Open
Abstract
Toxoplasmosis, caused by the apicomplexan parasite Toxoplasma gondii, is one of the most damaging parasite-borne zoonotic diseases of global importance. While approximately one-third of the entire world’s population is estimated to be infected with T. gondii, an effective vaccine for human use remains unavailable. Global efforts in pursuit of developing a T. gondii vaccine have been ongoing for decades, and novel innovative approaches have been introduced to aid this process. A wide array of vaccination strategies have been conducted to date including, but not limited to, nucleic acids, protein subunits, attenuated vaccines, and nanoparticles, which have been assessed in rodents with promising results. Yet, translation of these in vivo results into clinical studies remains a major obstacle that needs to be overcome. In this review, we will aim to summarize the current advances in T. gondii vaccine strategies and address the challenges hindering vaccine development.
Collapse
Affiliation(s)
- Ki-Back Chu
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea;
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447, Korea
- Correspondence:
| |
Collapse
|
9
|
Smith NC, Goulart C, Hayward JA, Kupz A, Miller CM, van Dooren GG. Control of human toxoplasmosis. Int J Parasitol 2020; 51:95-121. [PMID: 33347832 DOI: 10.1016/j.ijpara.2020.11.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/12/2020] [Accepted: 11/15/2020] [Indexed: 12/21/2022]
Abstract
Toxoplasmosis is caused by Toxoplasma gondii, an apicomplexan parasite that is able to infect any nucleated cell in any warm-blooded animal. Toxoplasma gondii infects around 2 billion people and, whilst only a small percentage of infected people will suffer serious disease, the prevalence of the parasite makes it one of the most damaging zoonotic diseases in the world. Toxoplasmosis is a disease with multiple manifestations: it can cause a fatal encephalitis in immunosuppressed people; if first contracted during pregnancy, it can cause miscarriage or congenital defects in the neonate; and it can cause serious ocular disease, even in immunocompetent people. The disease has a complex epidemiology, being transmitted by ingestion of oocysts that are shed in the faeces of definitive feline hosts and contaminate water, soil and crops, or by consumption of intracellular cysts in undercooked meat from intermediate hosts. In this review we examine current and future approaches to control toxoplasmosis, which encompass a variety of measures that target different components of the life cycle of T. gondii. These include: education programs about the parasite and avoidance of contact with infectious stages; biosecurity and sanitation to ensure food and water safety; chemo- and immunotherapeutics to control active infections and disease; prophylactic options to prevent acquisition of infection by livestock and cyst formation in meat; and vaccines to prevent shedding of oocysts by definitive feline hosts.
Collapse
Affiliation(s)
- Nicholas C Smith
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; Research School of Biology, Australian National University, Canberra, ACT 0200, Australia.
| | - Cibelly Goulart
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| | - Jenni A Hayward
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| | - Andreas Kupz
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia
| | - Catherine M Miller
- College of Public Health, Medical and Veterinary Science, James Cook University, Cairns, QLD 4878, Australia
| | - Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| |
Collapse
|
10
|
The Immunogenic and Immunoprotective Activities of Recombinant Chimeric T. gondii Proteins Containing AMA1 Antigen Fragments. Vaccines (Basel) 2020; 8:vaccines8040724. [PMID: 33276579 PMCID: PMC7761622 DOI: 10.3390/vaccines8040724] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 11/18/2020] [Accepted: 11/26/2020] [Indexed: 12/16/2022] Open
Abstract
Toxoplasmosis, one of the most common parasitoses worldwide, is potentially dangerous for individuals with a weakened immune system, but specific immunoprophylaxis intended for humans is still lacking. Thus, efforts have been made to create an efficient universal vaccine for both animals and humans to overcome the shortcomings of currently used treatment methods and protect all hosts against toxoplasmosis. The current work represents a relatively new approach to vaccine development based on recombinant chimeric Toxoplasma gondii antigens. In the present research, three tetravalent chimeric proteins containing different portions of the parasite’s AMA1 antigen—AMA1domainI-SAG2-GRA1-ROP1L (ANSGR), AMA1domainsII,III-SAG2-GRA1-ROP1L (ACSGR) and AMA1fullprotein-SAG2-GRA1-ROP1L (AFSGR)—were tested for their immunogenic and immunoprotective capacities. All tested proteins were immunogenic, as evidenced by the triggering of specific humoral and cellular immune responses in vaccinated C3H/HeOuJ mice, defined by the production of specific IgG (IgG1/IgG2a) antibodies in vivo and synthesis of key Th1/Th2 cytokines by Toxoplasma lysate antigen-stimulated splenocytes in vitro. Although all tested preparations provided partial protection against chronic toxoplasmosis in immunized and T. gondii-challenged mice, the intensity of the generated immunoprotection depended on the fragment of the AMA1 antigen incorporated into the chimeric antigen’s structure.
Collapse
|