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Moglad E, Elekhnawy E, Negm WA, Eliwa D, Sami Younis S, Mohamed Elmansory B, Mahgoub S, Ahmed EA, Momtaz Al-Fakhrany O. Antibacterial and anti-Toxoplasma activities of Aspergillus niger endophytic fungus isolated from Ficus retusa: in vitro and in vivo approach. Artif Cells Nanomed Biotechnol 2023; 51:297-308. [PMID: 37224186 DOI: 10.1080/21691401.2023.2215531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/01/2023] [Accepted: 04/11/2023] [Indexed: 05/26/2023]
Abstract
Emergent records propose that Aspergillus niger endophytic fungus is a vital source for various bioactive molecules possessing many biological properties. The current study was designed to inspect the antibacterial and anti-Toxoplasma potentials of Ficus retusa-derived endophytic fungi. After isolation and identification (using 18S rRNA gene sequencing) of A. niger endophytic fungus, LC/MS was utilized for identification and authentication of the chemical profile of the A. niger endophyte extract. Then, the fungal extract was assessed for its antibacterial and antibiofilm activities against Klebsiella pneumoniae clinical isolates. Additionally, its efficacy against Toxoplasma gondii was elucidated in vivo. The fungal extract displayed antibacterial activity against K. pneumoniae isolates with minimum inhibitory concentration values of 64-512 µg/mL. It also possessed a membrane potential dissipating effect using flow cytometry. Moreover, it formed distorted cells with rough surfaces and deformed shapes using a scanning electron microscope (SEM). Regarding its antibiofilm activity, it resulted in a dysregulation of the genes encoding biofilm formation (fimH, mrkA and mrkD) using qRT-PCR in nine K. pneumoniae isolates. The in vivo anti-Toxoplasma potential was demonstrated by decreasing the mortality rate of mice and reducing the tachyzoites' count in the peritoneal fluids and liver impression smears of mice. In addition, the deformities of the parasite decreased, as revealed by SEM and the inflammation in tissues diminished. Thus, A. niger endophytic fungi could be a valuable source of antibacterial and anti-Toxoplasma compounds.
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Affiliation(s)
- Ehssan Moglad
- Department of Pharmaceutics, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia
| | - Engy Elekhnawy
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Walaa A Negm
- Department of Pharmacognosy, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Duaa Eliwa
- Department of Pharmacognosy, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Salwa Sami Younis
- Department of Medical Parasitology, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | | | - Sebaey Mahgoub
- Department of Basic Research, Proteomics and Metabolomics Research Program, Children's Cancer Hospital 57357, Cairo, Egypt
| | - Eman A Ahmed
- Department of Basic Research, Proteomics and Metabolomics Research Program, Children's Cancer Hospital 57357, Cairo, Egypt
- Department of Pharmacology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, Egypt
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Li Z, Du W, Yang J, Lai DH, Lun ZR, Guo Q. Cryo-Electron Tomography of Toxoplasma gondii Indicates That the Conoid Fiber May Be Derived from Microtubules. Adv Sci (Weinh) 2023; 10:e2206595. [PMID: 36840635 DOI: 10.1002/advs.202206595] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/04/2023] [Indexed: 05/18/2023]
Abstract
Toxoplasma gondii (T. gondii) is the causative agent of toxoplasmosis and can infect numerous warm-blooded animals. An improved understanding of the fine structure of this parasite can help elucidate its replication mechanism. Previous studies have resolved the ultrastructure of the cytoskeleton using purified samples, which eliminates their cellular context. Here the application of cryo-electron tomography to visualize T. gondii tachyzoites in their native state is reported. The fine structure and cellular distribution of the cytoskeleton are resolved and analyzed at nanometer resolution. Additionally, the tachyzoite structural characteristics are annotated during its endodyogeny for the first time. By comparing the structural features in mature tachyzoites and their daughter buds, it is proposed that the conoid fiber of the Apicomplexa originates from microtubules. This work represents the detailed molecular anatomy of T. gondii, particularly during the budding replication stage of tachyzoite, and provides a reference for further studies of this fascinating organism.
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Affiliation(s)
- Zhixun Li
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing, 100871, P. R. China
| | - Wenjing Du
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing, 100871, P. R. China
| | - Jiong Yang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - De-Hua Lai
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Zhao-Rong Lun
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, P. R. China
| | - Qiang Guo
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing, 100871, P. R. China
- Changping Laboratory, Yard 28, Science Park Road, Beijing, 102206, P. R. China
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Ezzatkhah F, Mahmoudvand H, Raziani Y. The role of Curcuma longa essential oil in controlling acute toxoplasmosis by improving the immune system and reducing inflammation and oxidative stress. Front Cell Infect Microbiol 2023; 13:1161133. [PMID: 37249978 PMCID: PMC10214415 DOI: 10.3389/fcimb.2023.1161133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 04/06/2023] [Indexed: 05/31/2023] Open
Abstract
Background Chemotherapy with synthetic drugs is the principal approach for toxoplasmosis treatment; however, recent studies reported the limitations and adverse side effects of these chemical drugs. Objective This study aimed to examine the in vitro and in vivo effects of Curcuma longa essential oil (CLE) against the Toxoplasma gondii RH strain. Methods The in vitro effect of different concentrations of CLE on T. gondii tachyzoites was assessed by cell viability assay. Flow cytometry and apoptosis analysis were performed, and nitric oxide production by CLE was also evaluated in tachyzoites. BALB/c mice were orally treated with various doses (1.25, 2.5, and 5 mg·kg-1·day-1) of CLE for 2 weeks. After the induction of acute toxoplasmosis in the mice, their survival rate and the mean number of peritoneal parasites were checked. The hepatic level of antioxidant enzymes and oxidative stress markers was evaluated by commercial kits. The mRNA expression level of proinflammatory cytokines such as interleukin 1-beta (IL-1β) and interferon-gamma (IFN-γ) was evaluated by quantitative real-time PCR. Results CLE, especially at 50 µg/ml, showed potent inhibitory effects on T. gondii tachyzoites. It increased the survival rate (ninth day) and reduced the mean number of peritoneal tachyzoites in the infected mice. CLE dependently increased (p < 0.01) the number of necrotic and apoptotic cells as well as NO production. CLE significantly (p < 0.05) reduced the hepatic level of oxidative stress markers but increased (p < 0.001) the antioxidant enzymes and proinflammatory cytokines in the infected mice, with no important toxicity for vital organs. Conclusion The findings of this survey revealed the significant in vitro inhibitory effects of CLE on T. gondii tachyzoites. The results also exhibited promising in vivo effects of CLE. CLE improved the survival rate of infected mice and reduced the parasite number in them. Although the mechanisms of action of CLE are not clear, our study demonstrated its beneficial effects on acute toxoplasmosis by strengthening the immune system and reducing inflammation and oxidative stress. Still, more studies are required to confirm these results.
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Affiliation(s)
- Fatemeh Ezzatkhah
- Department of Laboratory Sciences, Sirjan School of Medical Sciences, Sirjan, Iran
| | - Hossein Mahmoudvand
- Razi Herbal Medicines Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Yosra Raziani
- Nursing Department, Al-Mustaqbal University College, Hillah, Babylon, Iraq
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Alnomasy SF. In vitro and in vivo Anti- Toxoplasma Effects of Allium sativum Essential Oil Against Toxoplasma gondii RH Strain. Infect Drug Resist 2021; 14:5057-5068. [PMID: 34876824 PMCID: PMC8643149 DOI: 10.2147/idr.s337905] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/03/2021] [Indexed: 11/23/2022] Open
Abstract
Background Since no effective vaccine has been developed for toxoplasmosis, prophylaxis in seronegative pregnant women and immunocompromised patients with a CD4 <100 cells/μL is highly recommended as an ideal strategy to prevent this disease. This study aimed to assess the chemical composition, in vitro, and in vivo effects of Allium sativum essential oil (ASEO) against Toxoplasma gondii RH strain. Methods The in vitro anti-Toxoplasma effects of different concentrations of ASEO (32.5, 75, 150 µg/mL) were measured by MTT assay for 0.5, 1, 2, and 3 h. Male Balb/c mice were orally administrated ASEO at the doses of 200, 400, and 600 µg/kg/day for 14 days. One day after the completion of oral drug administration, the mice in all groups were infected intraperitoneally with 1×104 tachyzoites. They were checked daily and the rate of survival was recorded. The peritoneal fluids of the mice were collected and the mean number of tachyzoites was calculated via a light microscope. The level of liver lipid peroxidation (LPO) and nitric oxide (NO), toxicity effects on the liver and kidney, and the mRNA expression levels of some pro-inflammatory cytokines such as IL-1β and IFN-γ were determined by quantitative real-time PCR. Results Different concentrations of ASEO showed a significant (p < 0.001) anti-Toxoplasma activity against T. gondii tachyzoites, and the highest efficacy was observed at the concentration of 150 µg/mL. Fourteen days of pre-treatment of infected mice with ASEO at the doses of 200, 400, and 600 µg/kg/day significantly (p < 0.001) decreased the mean number of tachyzoites and mortality rate by the 6th, 7th, and 8th days after infection, respectively. ASEO at the doses of 200, 400, and 600 µg/kg/day significantly (p < 0.05) improved the increase in the LPO and NO. Pre-treatment of mice with different doses of ASEO provoked a considerable (P < 0.001) downregulation of IL-1β and IFN-γ mRNA gene expression levels, but it had no significant toxicity on the serum levels of some liver and kidney enzymes. Conclusion The present study demonstrated the considerable prophylactic effects of ASEO that increased the survival rate of mice and reduced the parasite load in them. Our findings also showed that ASEO promotes the innate immune system, pro-inflammatory cytokines, inhibition of hepatic injury, etc. in the mice with acute toxoplasmosis. However, additional investigations are mandatory to clarify the accurate prophylactic and therapeutic anti-Toxoplasma mechanisms of ASEO as well as all its toxicity aspects, especially in clinical settings.
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Affiliation(s)
- Sultan F Alnomasy
- Department of Medical Laboratories Sciences, College of Applied Medical Sciences in Al-Quwayiyah, Shaqra University, Riyadh, Saudi Arabia
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Ramseier J, Imhof D, Anghel N, Hänggeli K, Beteck RM, Balmer V, Ortega-Mora LM, Sanchez-Sanchez R, Ferre I, Haynes RK, Hemphill A. Assessment of the Activity of Decoquinate and Its Quinoline- O-Carbamate Derivatives against Toxoplasma gondii In Vitro and in Pregnant Mice Infected with T. gondii Oocysts. Molecules 2021; 26:6393. [PMID: 34770802 DOI: 10.3390/molecules26216393] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/14/2021] [Accepted: 10/20/2021] [Indexed: 11/16/2022] Open
Abstract
The quinolone decoquinate (DCQ) is widely used in veterinary practice for the treatment of bacterial and parasitic infections, most notably, coccidiosis in poultry and in ruminants. We have investigated the effects of treatment of Toxoplasma gondii in infected human foreskin fibroblasts (HFF) with DCQ. This induced distinct alterations in the parasite mitochondrion within 24 h, which persisted even after long-term (500 nM, 52 days) treatment, although there was no parasiticidal effect. Based on the low half-maximal effective concentration (IC50) of 1.1 nM and the high selectivity index of >5000, the efficacy of oral treatment of pregnant mice experimentally infected with T. gondii oocysts with DCQ at 10 mg/kg/day for 5 days was assessed. However, the treatment had detrimental effects, induced higher neonatal mortality than T. gondii infection alone, and did not prevent vertical transmission. Thus, three quinoline-O-carbamate derivatives of DCQ, anticipated to have better physicochemical properties than DCQ, were assessed in vitro. One such compound, RMB060, displayed an exceedingly low IC50 of 0.07 nM, when applied concomitantly with the infection of host cells and had no impact on HFF viability at 10 µM. As was the case for DCQ, RMB060 treatment resulted in the alteration of the mitochondrial matrix and loss of cristae, but the changes became apparent at just 6 h after the commencement of treatment. After 48 h, RMB060 induced the expression of the bradyzoite antigen BAG1, but TEM did not reveal any other features reminiscent of bradyzoites. The exposure of infected cultures to 300 nM RMB060 for 52 days did not result in the complete killing of all tachyzoites, although mitochondria remained ultrastructurally damaged and there was a slower proliferation rate. The treatment of mice infected with T. gondii oocysts with RMB060 did reduce parasite burden in non-pregnant mice and dams, but vertical transmission to pups could not be prevented.
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Bahreini MS, Nohtani M, Salemi AM, Mirzaeipour M, Dastan N, Bajelan S, Asgari Q. Introduction of protocols for mass production of Toxoplasma gondii tachyzoites of the genotype II PRU strain. Animal Model Exp Med 2021; 4:278-282. [PMID: 34557654 PMCID: PMC8446697 DOI: 10.1002/ame2.12174] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 05/17/2021] [Indexed: 11/23/2022] Open
Abstract
Background Few investigations of genotype II of Toxoplasma gondii, the most prevalent form of the Toxoplasma parasite in humans, have been carried out on due to the rapid conversion of tachyzoites to bradyzoites in its life cycle. The current study aimed to create animal and in vitro models for production of the tachyzoites of the Prugniaud (PRU) genotype II strain. Methods To develop an immunocompromised model and obtain tachyzoites of the PRU strain, BALB/c mice were orally treated with dexamethasone (10 mg/kg), cyclophosphamide (36 mg/kg), and cyclosporine (18 mg/kg) from 5 days prior to inoculation. Then, 10-15 tissue cysts of PRU strain were inoculated intraperitoneally into the mice. The tachyzoites obtained from mice were then cultivated in a HeLa cell culture. The resulting yield of tachyzoites was cryopreserved in 92% fetal calf serum, 8% dimethyl sulfoxide. The infectivity of these tachyzoites was evaluated using in vivo and in vitro examinations. Results Numerous tachyzoites were observed in the peritoneal fluid of the immunosuppressed mice within 10-15 days after inoculation, and many tachyzoites were harvested from the HeLa cell culture. Trypan Blue staining showed 80% viability of the tachyzoites recovered from cryopreservation and this was confirmed by HeLa cell culture. In addition, mice infected intraperitoneally with the recovered tachyzoites presented with cysts in the brain after 2 months. Conclusion We have developed an animal model for mass production of T. gondii tachyzoites of the PRU strain. This method can provide fresh viable tachyzoites of Toxoplasma gondii for use as and when required in future investigations.
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Affiliation(s)
- Mohammad Saleh Bahreini
- Department of Medical Parasitology and MycologySchool of MedicineShiraz University of Medical SciencesShirazIran
| | - Mohammad Nohtani
- Department of Medical Parasitology and MycologySchool of MedicineShiraz University of Medical SciencesShirazIran
| | - Amir Masoud Salemi
- Department of Medical Parasitology and MycologySchool of MedicineShiraz University of Medical SciencesShirazIran
| | - Mehdi Mirzaeipour
- Department of Medical Parasitology and MycologySchool of MedicineShiraz University of Medical SciencesShirazIran
| | - Naghmeh Dastan
- Department of Medical Parasitology and MycologySchool of MedicineShiraz University of Medical SciencesShirazIran
| | - Sara Bajelan
- Department of Medical Parasitology and MycologySchool of MedicineShiraz University of Medical SciencesShirazIran
| | - Qasem Asgari
- Department of Medical Parasitology and MycologySchool of MedicineShiraz University of Medical SciencesShirazIran
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Quiarim TM, Maia MM, da Cruz AB, Taniwaki NN, Namiyama GM, Pereira-Chioccola VL. Characterization of extracellular vesicles isolated from types I, II and III strains of Toxoplasma gondii. Acta Trop 2021; 219:105915. [PMID: 33861971 DOI: 10.1016/j.actatropica.2021.105915] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/15/2021] [Accepted: 03/27/2021] [Indexed: 12/31/2022]
Abstract
This study investigated the participation extracellular vesicles (EVs) in Toxoplasma gondii-host interaction. EVs of three T. gondii strains (RH, ME-49 and VEG) were purified by chromatography and ELISA. Results of "nanoparticle tracking analysis" and scanning electron microscopy showed that RH strain released more EVs than other strains. Images of transmission electron microscopy showed that in beginning of incubation (culture medium), EVs were inside of tachyzoites preparing to be released. After 24 hours, they were largely produced inside tachyzoites and were released through plasma membrane. The parasite burden of mice infected with RH strain plus EVs was increased and with early death of 1-2 days compared of those that received only parasites. EV proteins of ME-49 and VEG strains were poorly reactive to sera of infected patients in imunoblot. However, those from RH strain were reactive against sera of patients with cerebral toxoplasmosis. EVs stimulated murine splenocytes caused similar production of IFN-γ and IL-10 levels. RH strain derived EVs stimulated more TNF-α than those stimulated by other strains. T. gondii and infected hosts can express the same miRNAs (miR-155-5p, miR-125b-5p, miR-423-3p). In conclusion, T. gondii derived EVs promote host-parasite interactions, modulate host immune responses, carry virulent factors and cause an imbalance in cellular immune response.
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Affiliation(s)
- Talita Motta Quiarim
- Laboratório de Biologia Molecular de Parasitas e Fungos, Instituto Adolfo Lutz, Sao Paulo, Brazil.
| | - Marta Marques Maia
- Laboratório de Biologia Molecular de Parasitas e Fungos, Instituto Adolfo Lutz, Sao Paulo, Brazil.
| | - Allecineia Bispo da Cruz
- Laboratório de Biologia Molecular de Parasitas e Fungos, Instituto Adolfo Lutz, Sao Paulo, Brazil.
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Hamie M, Tawil N, El Hajj R, Najm R, Moodad S, Hleihel R, Karam M, El Sayyed S, Besteiro S, El-Sabban M, Dubremetz JF, Lebrun M, El Hajj H. P18 (SRS35/TgSAG4) Plays a Role in the Invasion and Virulence of Toxoplasma gondii. Front Immunol 2021; 12:643292. [PMID: 34262559 PMCID: PMC8273438 DOI: 10.3389/fimmu.2021.643292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 06/10/2021] [Indexed: 11/13/2022] Open
Abstract
Toxoplasmosis is a prevalent parasitic disease caused by Toxoplasma gondii (T. gondii). Under the control of the host immune system, T. gondii persists as latent bradyzoite cysts. Immunosuppression leads to their reactivation, a potentially life-threatening condition. Interferon-gamma (IFN-γ) controls the different stages of toxoplasmosis. Here, we addressed the role of the parasite surface antigen P18, belonging to the Surface-Antigen 1 (SAG-1) Related Sequence (SRS) family, in a cyst-forming strain. Deletion of P18 gene (KO P18) impaired the invasion of parasites in macrophages and IFN-γ-mediated activation of macrophages further reduced the invasion capacity of this KO, as compared to WT strain. Mice infected by KO P18, showed a marked decrease in virulence during acute toxoplasmosis. This was consequent to less parasitemia, accompanied by a substantial recruitment of dendritic cells, macrophages and natural killer cells (NK). Furthermore, KO P18 resulted in a higher number of bradyzoite cysts, and a stronger inflammatory response. A prolonged survival of mice was observed upon immunosuppression of KO P18 infected BALB/c mice or upon oral infection of Severe Combined Immunodeficiency (SCID) mice, with intact macrophages and natural killer (NK) cells. In stark contrast, oral infection of NSG (NOD/Shi-scid/IL-2Rγnull) mice, defective in macrophages and NK cells, with KO P18, was as lethal as that of the control strain showing that the conversion from bradyzoites to tachyzoites is intact and, suggesting a role of P18 in the response to host IFN-γ. Collectively, these data demonstrate a role for P18 surface antigen in the invasion of macrophages and in the virulence of the parasite, during acute and chronic toxoplasmosis.
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Affiliation(s)
- Maguy Hamie
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Nadim Tawil
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Rana El Hajj
- Department of Biological Sciences, Beirut Arab University, Beirut, Lebanon
| | - Rania Najm
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Sara Moodad
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Rita Hleihel
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Martin Karam
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Sana El Sayyed
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | | | - Marwan El-Sabban
- Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | | | - Maryse Lebrun
- LPHI UMR5235, Univ Montpellier, CNRS, Montpellier, France
| | - Hiba El Hajj
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
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Augusto L, Wek RC, Sullivan WJ. Host sensing and signal transduction during Toxoplasma stage conversion. Mol Microbiol 2020; 115:839-848. [PMID: 33118234 DOI: 10.1111/mmi.14634] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 10/20/2020] [Accepted: 10/24/2020] [Indexed: 12/14/2022]
Abstract
The intracellular parasite Toxoplasma gondii infects nucleated cells in virtually all warm-blooded vertebrates, including one-third of the human population. While immunocompetent hosts do not typically show symptoms of acute infection, parasites are retained in latent tissue cysts that can be reactivated upon immune suppression, potentially damaging key organ systems. Toxoplasma has a multistage life cycle that is intimately linked to environmental stresses and host signals. As this protozoan pathogen is transmitted between multiple hosts and tissues, it evaluates these external signals to appropriately differentiate into distinct life cycle stages, such as the transition from its replicative stage (tachyzoite) to the latent stage (bradyzoite) that persists as tissue cysts. Additionally, in the gut of its definitive host, felines, Toxoplasma converts into gametocytes that produce infectious oocysts (sporozoites) that are expelled into the environment. In this review, we highlight recent advances that have illuminated the interfaces between Toxoplasma and host and how these interactions control parasite stage conversion. Mechanisms underlying these stage transitions are important targets for therapeutic intervention aimed at thwarting parasite transmission and pathogenesis.
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Affiliation(s)
- Leonardo Augusto
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ronald C Wek
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - William J Sullivan
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA.,Department of Microbiology & Immunology, Indiana University School of Medicine, Indianapolis, IN, USA
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Ammar S, Hoggard N, Wood L, Su C, Gerhold R. Toxoplasma gondii Strain and Dose Effects on Feed Conversion Rate, Body Weight, Serum Antibodies Response, and Systemic Distribution in Intraperitoneally Infected Domestic Turkey Poults. Avian Dis 2020; 65:138-148. [PMID: 34339133 DOI: 10.1637/aviandiseases-d-20-00104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/18/2020] [Indexed: 11/05/2022]
Abstract
Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is an important foodborne zoonosis affecting a wide range of hosts, including birds. This study investigated the seroconversion, feed conversion rate, weight gain, and parasite tissue tropism as a function of parasite dose and virulence in turkeys. Twenty-five 4-wk-old female domestic turkeys (Meleagris gallapavo) were intraperitoneally infected with two different strains and two doses (105 and 108 tachyzoites/ml) of T. gondii tachyzoites, resulting in four treatment groups. A fifth group of 10 additional birds was intraperitoneally injected with sterile phosphate-buffered saline as a negative control. All birds remained subclinical except for three birds in the two high-dose groups (108 tachyzoites/ml). Survival rate was 88% (22/25). A 92% seroconversion rate was detected in T. gondii-infected birds using a modified agglutination test. Antibody titers as well as weight gain were related to the dose and strain of T. gondii used. Feed conversion rate was higher in the high-dose groups compared with low-dose and control groups, while weight gain was significantly lower at 14 days postinfection in the group infected with 108 tachyzoites/ml of virulent T. gondii strain. Gross lesions were detected in the pancreas and lungs of only one bird, and histopathologic findings varied depending on strain and dose. The organs that most frequently contained T. gondii DNA as detected by quantitative PCR were the brain and the heart, followed by the bursa of Fabricius and the lungs. This study confirmed that turkeys can be infected with T. gondii, and turkeys can show signs of infection when exposed to high doses. Given the increased practice of outdoor-raised livestock and wildlife consumption, continual experimental infection of T. gondii in wild and domestic animals should be pursued.
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Affiliation(s)
- Sawsan Ammar
- Department of Biomedical and Diagnostic Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996.,Department of Clinical Pathology, Faculty of Veterinary Medicine, Sadat City University, Sadat City, Menofia, Egypt 32511
| | - Nathan Hoggard
- Department of Biomedical and Diagnostic Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996
| | - Liberty Wood
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996
| | - Chunlei Su
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996
| | - Richard Gerhold
- Department of Biomedical and Diagnostic Sciences, University of Tennessee, College of Veterinary Medicine, Knoxville, TN 37996,
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Esboei BR, Keighobadi M, Hezarjaribi HZ, Fakhar M, Daryani A, Chabra A, Soosaraei M, Yalveh R. Promising In Vitro Anti- Toxoplasma gondii Effects of Commercial Chitosan. Infect Disord Drug Targets 2020; 21:151-155. [PMID: 32389115 DOI: 10.2174/1871526520666200511004932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 03/29/2020] [Accepted: 04/05/2020] [Indexed: 11/22/2022]
Abstract
CDATA[Background: Toxoplasmosis is a disease that results from infection with an obligate intracellular T. gondii parasite, one of the world's most common parasites. Considering the complications of chemical drugs and the need for an appropriate drug combination for treatment of toxoplasmosis and considering the antimicrobial potential of chitosan, as a natural source, this study was aimed to evaluate in vitro activity of commercial chitosan (CC) on T. gondii. METHODS In this experimental study, the tachyzoites of T. gondii were collected from the peritoneal exudates from infected Balb/c mice. The tachyzoites were diluted in phosphate buffer saline (PBS) solution. Chitosan with low molecular weight was commercially purchased. Then, at concentrations of 10, 50, 100, and 200 μg/mL and after 30, 60, 120, and 180 minutes, the viability of tachyzoites was determined by using trypan blue 0.1%. Anti-T.gondii activity of CC in all concentrations was significantly higher than pyrimethamine as the control group (P=0.05). RESULTS The concentration of 200 μg/mL of CC had the highest effects and killed 30.5, 52, 59, and 81.5% of tachyzoites after 30, 60, 120, and 180 minutes. Moreover, IC50 values of CC were 515, 171, 12.5, and <10 μg/mL in comparison with pyrimethamine as 58.82 μg/mL for 30, 60, 120, and 180 min of exposure time. CONCLUSION Our results indicate that chitosan in low molecular weight had potent activity against T. gondii tachyzoites and could be an appropriate candidate for the treatment of at least acute toxoplasmosis, certainly, after complementary in vivo experiments.
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Affiliation(s)
- Bahman Rahimi Esboei
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Masoud Keighobadi
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Hajar Ziaei Hezarjaribi
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mahdi Fakhar
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Ahmad Daryani
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Aroona Chabra
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Masoud Soosaraei
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Rezwan Yalveh
- Toxoplasmosis Research Center, Department of Parasitology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
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Salas-Lais AG, Robles-Contreras A, Balderas-López JA, Bautista-de Lucio VM. Immunobiotic and Paraprobiotic Potential Effect of Lactobacillus casei in a Systemic Toxoplasmosis Murine Model. Microorganisms 2020; 8:E113. [PMID: 31947510 DOI: 10.3390/microorganisms8010113] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 12/20/2022] Open
Abstract
One of the main characteristics of probiotics is their ability to stimulate and modulate the immune response regardless of their viability. Lactobacillus casei (Lc) can stimulate local and systemic immunity, in addition to the activation of macrophages at sites distant from the intestine. Activated macrophages limit the replication of intracellular protozoa, such as Toxoplasma gondii, through the production of nitric oxide. The present study aimed to evaluate the protection generated by treatment with viable and non-viable Lc in the murine systemic toxoplasmosis model. CD1 male mice were treated with viable Lc (immunobiotic) and non-viable Lc (paraprobiotic), infected with tachyzoites of Toxoplasma gondii RH strain. The reduction of the parasitic load, activation of peritoneal macrophages, inflammatory cytokines, and cell populations was evaluated at 7 days post-infection, in addition to the survival. The immunobiotic and paraprobiotic reduced the parasitic load, but only the immunobiotic increased the activation of peritoneal macrophages, and the production of interferon-gamma (IFN-γ), tumor necrosis factor (TNF), and interleukin-6 (IL-6) while the paraprobiotic increased the production of monocyte chemoattractant protein-1 (MCP-1) and T CD4+CD44+ lymphocytes. Viable and non-viable Lc increases survival but does not prevent the death of animals. The results provide evidence about the remote immunological stimulation of viable and non-viable Lc in an in vivo parasitic model.
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Subramanian G, Belekar MA, Shukla A, Tong JX, Sinha A, Chu TTT, Kulkarni AS, Preiser PR, Reddy DS, Tan KSW, Shanmugam D, Chandramohanadas R. Targeted Phenotypic Screening in Plasmodium falciparum and Toxoplasma gondii Reveals Novel Modes of Action of Medicines for Malaria Venture Malaria Box Molecules. mSphere 2018; 3:e00534-17. [PMID: 29359192 DOI: 10.1128/mSphere.00534-17] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 12/20/2017] [Indexed: 01/23/2023] Open
Abstract
The Malaria Box collection includes 400 chemically diverse small molecules with documented potency against malaria parasite growth, but the underlying modes of action are largely unknown. Using complementary phenotypic screens against Plasmodium falciparum and Toxoplasma gondii, we report phenotype-specific hits based on inhibition of overall parasite growth, apicoplast segregation, and egress or host invasion, providing hitherto unavailable insights into the possible mechanisms affected. First, the Malaria Box library was screened against tachyzoite stage T. gondii and the half-maximal effective concentrations (EC50s) of molecules showing ≥80% growth inhibition at 10 µM were determined. Comparison of the EC50s for T. gondii and P. falciparum identified a subset of 24 molecules with nanomolar potency against both parasites. Thirty molecules that failed to induce acute growth inhibition in T. gondii tachyzoites in a 2-day assay caused delayed parasite death upon extended exposure, with at least three molecules interfering with apicoplast segregation during daughter cell formation. Using flow cytometry and microscopy-based examinations, we prioritized 26 molecules with the potential to inhibit host cell egress/invasion during asexual developmental stages of P. falciparum. None of the inhibitors affected digestive vacuole integrity, ruling out a mechanism mediated by broadly specific protease inhibitor activity. Interestingly, five of the plasmodial egress inhibitors inhibited ionophore-induced egress of T. gondii tachyzoites. These findings highlight the advantage of comparative and targeted phenotypic screens in related species as a means to identify lead molecules with a conserved mode of action. Further work on target identification and mechanism analysis will facilitate the development of antiparasitic compounds with cross-species efficacy. IMPORTANCE The phylum Apicomplexa includes many human and animal pathogens, such as Plasmodium falciparum (human malaria) and Toxoplasma gondii (human and animal toxoplasmosis). Widespread resistance to current antimalarials and the lack of a commercial vaccine necessitate novel pharmacological interventions with distinct modes of action against malaria. For toxoplasmosis, new drugs to effectively eliminate tissue-dwelling latent cysts of the parasite are needed. The Malaria Box antimalarial collection, managed and distributed by the Medicines for Malaria Venture, includes molecules of novel chemical classes with proven antimalarial efficacy. Using targeted phenotypic assays of P. falciparum and T. gondii, we have identified a subset of the Malaria Box molecules as potent inhibitors of plastid segregation and parasite invasion and egress, thereby providing early insights into their probable mode of action. Five molecules that inhibit the egress of both parasites have been identified for further mechanistic studies. Thus, the approach we have used to identify novel molecules with defined modes of action in multiple parasites can expedite the development of pan-active antiparasitic agents.
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Abstract
Toxoplasmosis is generally asymptomatic in immunocompetent individuals, but it can be life-threatening in immunocompromised patients. We present a case of a 62-year-old man with clinical features of acute appendicitis. Histology showed a transmural infiltrate of eosinophils. In addition, there were reactive lymphoid follicles with histiocytes in the submucosa and tachyzoites in the muscularis propria. Immunohistochemistry confirmed the diagnosis of toxoplasma appendicitis. Serological evaluation yielded negative results. Retrospective review of the history revealed that the patient was on long-term immunosuppressive therapy with methotrexate. The patient was treated with sulfamethoxazole-trimethoprim and is asymptomatic at 7-month follow-up. Toxoplasma appendicitis must be considered in the differential diagnosis of appendicitis in immunosuppressed patients.
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Affiliation(s)
| | | | - Sanjay A Pai
- 1 Columbia Asia Referral Hospital, Bangalore, India
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15
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Ness SL, Schares G, Peters-Kennedy J, Mittel LD, Dubey JP, Bowman DD, Mohammed HO, Divers TJ. Serological diagnosis of Besnoitia bennetti infection in donkeys (Equus asinus). J Vet Diagn Invest 2014; 26:778-82. [PMID: 25227418 DOI: 10.1177/1040638714550180] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Besnoitiosis is an emerging infectious disease of donkeys (Equus asinus) in the United States for which there are currently no serologic methods of diagnosis. A study was performed to evaluate physical examination findings and 3 serologic assays for the detection of Besnoitia bennetti infection in donkeys. A prospective study of 416 donkeys from 6 privately owned herds across 5 U.S. states (New York, Pennsylvania, Vermont, Oregon, and Washington) was performed. Donkeys were examined for clinical lesions suggestive of besnoitiosis and evaluated for antibodies against B. bennetti using a fluorescent antibody test (FAT) and 2 immunoblot assays specific for bradyzoite and tachyzoite antigens, respectively. Donkeys were confirmed to be infected with B. bennetti by histology (cases; n = 32) and were compared to those with no clinical signs of besnoitiosis (controls; n = 384). Identifying clinical lesions in 2 or more locations correctly identified infected donkeys 83% of the time. Donkeys with besnoitiosis had significantly higher FAT titers (P < 0.001) and numbers of bradyzoite (P < 0.001) and tachyzoite (P < 0.001) immunoblot bands than control donkeys. The sensitivity and specificity of the serologic assays for detecting besnoitiosis was 88% and 96% for FAT, 81% and 91% for bradyzoite immunoblot, and 91% and 92% for tachyzoite immunoblot, respectively. Fluorescent antibody and immunoblot assays are effective at identifying donkeys with besnoitiosis and provide a more efficient and less invasive diagnostic alternative to histology.
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Affiliation(s)
- SallyAnne L Ness
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
| | - Gereon Schares
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
| | - Jeanine Peters-Kennedy
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
| | - Linda D Mittel
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
| | - Jitender P Dubey
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
| | - Dwight D Bowman
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
| | - Hussni O Mohammed
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
| | - Thomas J Divers
- Departments of Clinical Sciences (Ness, Divers), College of Veterinary Medicine, Cornell University, Ithaca, NYBiomedical Sciences (Peters-Kennedy), College of Veterinary Medicine, Cornell University, Ithaca, NYPopulation Medicine and Diagnostic Sciences (Mittel, Mohammed), College of Veterinary Medicine, Cornell University, Ithaca, NYMicrobiology and Immunology (Bowman), College of Veterinary Medicine, Cornell University, Ithaca, NYFriedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Epidemiology, Greifswald, Isle of Riems, Germany (Schares)Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD (Dubey)
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