1
|
Identification of Oocyst-Driven Toxoplasma gondii Infections in Humans and Animals through Stage-Specific Serology-Current Status and Future Perspectives. Microorganisms 2021; 9:microorganisms9112346. [PMID: 34835471 PMCID: PMC8618849 DOI: 10.3390/microorganisms9112346] [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: 10/04/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/17/2022] Open
Abstract
The apicomplexan zoonotic parasite Toxoplasma gondii has three infective stages: sporozoites in sporulated oocysts, which are shed in unsporulated form into the environment by infected felids; tissue cysts containing bradyzoites, and fast replicating tachyzoites that are responsible for acute toxoplasmosis. The contribution of oocysts to infections in both humans and animals is understudied despite being highly relevant. Only a few diagnostic antigens have been described to be capable of discriminating which parasite stage has caused an infection. Here we provide an extensive overview of the antigens and serological assays used to detect oocyst-driven infections in humans and animals according to the literature. In addition, we critically discuss the possibility to exploit the increasing knowledge of the T. gondii genome and the various 'omics datasets available, by applying predictive algorithms, for the identification of new oocyst-specific proteins for diagnostic purposes. Finally, we propose a workflow for how such antigens and assays based on them should be evaluated to ensure reproducible and robust results.
Collapse
|
2
|
Liyanage KLDTD, Wiethoelter A, Hufschmid J, Jabbar A. Descriptive Comparison of ELISAs for the Detection of Toxoplasma gondii Antibodies in Animals: A Systematic Review. Pathogens 2021; 10:605. [PMID: 34063342 PMCID: PMC8157005 DOI: 10.3390/pathogens10050605] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/03/2021] [Accepted: 05/12/2021] [Indexed: 11/16/2022] Open
Abstract
Toxoplasma gondii is the zoonotic parasite responsible for toxoplasmosis in warm-blooded vertebrates. This systematic review compares and evaluates the available knowledge on enzyme-linked immunosorbent assays (ELISAs), their components, and performance in detecting T. gondii antibodies in animals. Four databases were searched for published scientific studies on T. gondii and ELISA, and 57 articles were included. Overall, indirect (95%) and in-house (67%) ELISAs were the most used types of test among the studies examined, but the 'ID Screen® Toxoplasmosis Indirect Multi-species' was common among commercially available tests. Varying diagnostic performance (sensitivity and specificity) and Kappa agreements were observed depending on the type of sample (serum, meat juice, milk), antigen (native, recombinant, chimeric) and antibody-binding reagents used. Combinations of recombinant and chimeric antigens resulted in better performance than native or single recombinant antigens. Protein A/G appeared to be useful in detecting IgG antibodies in a wide range of animal species due to its non-species-specific binding. One study reported cross-reactivity, with Hammondia hammondi and Eimeria spp. This is the first systematic review to descriptively compare ELISAs for the detection of T. gondii antibodies across different animal species.
Collapse
Affiliation(s)
- K. L. D. Tharaka D. Liyanage
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, VIC 3030, Australia; (A.W.); (J.H.); (A.J.)
| | | | | | | |
Collapse
|
3
|
Diezma-Díaz C, Ferre I, Saldias B, Blanco-Murcia J, Ortega-Mora LM, Álvarez-García G. Added value of IgM detection and low avidity index as markers of acute bovine besnoitiosis. Vet Parasitol 2019; 277:109012. [PMID: 31884316 DOI: 10.1016/j.vetpar.2019.109012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 12/10/2019] [Accepted: 12/11/2019] [Indexed: 12/17/2022]
Abstract
Early in vivo diagnosis of bovine besnoitiosis is crucial for the success of control programmes. However, diagnosis in acutely infected animals is hindered by the low sensitivity of the available serological tools. In this study, a novel ELISA to detect specific anti-Besnoitia besnoiti IgM antibodies was developed. The usefulness of this tool together with an avidity ELISA were studied with a well-coded sera panel from experimentally and naturally infected cattle. First, the kinetics of specific IgM levels were determined in experimentally infected calves during the acute and chronic infection. Next, IgM levels were determined in naturally infected cattle with either acute or chronic infection. Finally, the IgG avidity index was monitored in both experimentally and naturally infected cattle. Specific IgM antibodies were detected prior to specific IgG antibodies (7-19 days vs. 17-26 days post-infection). A prompt IgM response was associated with the end of the febrile stage in experimentally infected calves. Naturally and experimentally infected animals with acute clinical signs tested IgM-positive but IgG-negative, followed by IgG seroconversion 2-3 weeks later. Chronically infected cattle developed both IgM and IgG specific antibodies. Moreover, a progressive increase in the avidity index (AI) was observed in all experimentally infected calves during the course of the experimental trials. However, a low AI coincided with visible tissue cysts. Low avidity values were also detected when naturally infected cattle with acute clinical signs seroconverted, in contrast to a high AI detected in chronically infected cattle. In summary, IgM and avidity ELISAs improved the early in vivo diagnosis of bovine besnoitiosis. IgM-positive but IgG-negative results were indicative of an acute infection, whereas IgG positive results accompanied by low avidity values confirmed a recent infection.
Collapse
Affiliation(s)
- Carlos Diezma-Díaz
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Ignacio Ferre
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Begonia Saldias
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Javier Blanco-Murcia
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain; Animal Medicine and Surgery Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Luis Miguel Ortega-Mora
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
| | - Gema Álvarez-García
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
| |
Collapse
|
4
|
Toxoplasmosis in sheep—The last 20 years. Vet Parasitol 2009; 163:1-14. [DOI: 10.1016/j.vetpar.2009.02.026] [Citation(s) in RCA: 264] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 02/23/2009] [Accepted: 02/27/2009] [Indexed: 11/22/2022]
|
5
|
Conde de Felipe MM, Molina JM, Rodríguez-Ponce E, Ruiz A, González JF. IGM and IGG response to 29-35-kDa Toxoplasma gondii protein fractions in experimentally infected goats. J Parasitol 2007; 93:701-3. [PMID: 17626367 DOI: 10.1645/ge-993r.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The evolution of the humoral responses of IgG and IgM against 29-35-kDa Toxoplasma gondii fractions from experimentally infected goats were studied and compared by ELISA with the use of whole T. gondii soluble extracts and 29-35-kDa electroeluted proteins as antigens. The IgM response to electroeluted proteins was detected from wk 1 to wk 3 postinfection, showing a similar evolution to that observed when T. gondii crude extracts were used as antigens. These results suggest that this group of proteins could be used for a more specific detection of anti-T. gondii IgM. In the same way, the IgG response was equivalent in both cases, although when 29-35-kDa T. gondii fractions were used as antigens, the level of specific IgGs reached a peak 2 wk before than when T. gondii crude extract was used. The detection by ELISA of anti-T. gondii IgM in goats does not seem to be affected by the presence of specific IgG in serum samples when 29-35-kDa protein fractions were used as antigens.
Collapse
Affiliation(s)
- M M Conde de Felipe
- Parasitic Diseases Unit, Faculty of Veterinary Medicine, University of Las Palmas de G. C., Trasmontaria s/n, 35416-Arucas, Las Palmas, Spain
| | | | | | | | | |
Collapse
|
6
|
Werre SR, Jacobson RH, Bowman DD, Dubey JP, Mohammed HO. Evaluation of kinetics and single-read enzyme-linked immunoassays for detection of Toxoplasma gondii antibodies in sheep. J Vet Diagn Invest 2002; 14:225-30. [PMID: 12033678 DOI: 10.1177/104063870201400306] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A kinetics enzyme-linked immunosorbent assay (ELISA) and a single-read ELISA for the detection of ovine anti-Toxoplasma gondii IgG were developed and optimized. During the kinetics assay, 3 optical densities were obtained for each serum sample at intervals of 45 seconds, and the results were presented as average slopes (replicates of 2) of the reaction rate between bound enzyme and substrate solution. The kinetics ELISA was stopped 5 minutes after dispensing the substrate to constitute the single-read ELISA, and the results were presented as average optical densities for duplicates of each sample. Performance of the assays was evaluated using the modified agglutination test (MAT) as the "gold standard." There was a high level of agreement between both ELISAs and the MAT, as measured by Pearson correlation coefficients, kappa statistics, and the area under the receiver operating characteristics curves. The single-read ELISA was as accurate as the kinetics ELISA, with a sensitivity of 89% and a specificity of 96%.
Collapse
Affiliation(s)
- Stephen R Werre
- Department of Population Medicine and Diagnostic Science, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | | | | | | | | |
Collapse
|
7
|
Francis JM, Payne RA, Joynson DH. Rapid indirect enzyme linked immunosorbent assay (ELISA) for detecting antitoxoplasma IgG: comparison with dye test. J Clin Pathol 1988; 41:802-5. [PMID: 3261740 PMCID: PMC1141591 DOI: 10.1136/jcp.41.7.802] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A rapid and simple enzyme linked immunosorbent assay (ELISA) for the detection of specific IgG against Toxoplasma gondii was compared with the dye test on 533 serum samples. In general, results were comparable but not with sera that contained high concentrations of toxoplasma specific IgM or that had been heated at 56 degrees C. There were no false positive results with sera containing rheumatoid factor or anti-nuclear factor. It is concluded that if a dye test is not to be performed then the serum should be tested for both toxoplasma specific IgG and IgM to avoid misleading results. Heat inactivated serum should also not be tested in this type of specific IgG assay.
Collapse
Affiliation(s)
- J M Francis
- Public Health Laboratory, Singleton Hospital, Swansea
| | | | | |
Collapse
|