Evaluation of RE and B1 Genes as Targets for Detection of Toxoplasma gondii by Nested PCR in Blood Samples of Patients with Ocular Toxoplasmosis
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To evaluate B1 and RE genes as targets to detect Toxoplasma gondii, nested PCR is used in blood samples of patients with ocular toxoplasmosis.
Materials and Methods
Following the measurement of IgG and IgM antibodies using indirect ELISA, IgG avidity and assessment of blood samples by nested PCR, the agreement between various test results was studied.
From 117 patients, 77 (65.81%) were found to be positive for IgG anti-Toxoplasma antibody, 12 cases were positive for both IgG and IgM, and 1 patient was positive for IgM only. The detection limit for the RE-nested PCR assay was one T. gondii tachyzoite, whereas the limit for B1-nested PCR was five tachyzoites. Nested PCR results showed higher agreement with IgM test results than IgG test results.
The results of this study showed that nested PCR of peripheral blood is a useful and non-invasive method for detection of T. gondii in patients with OT, especially in case of recently acquired infections, and RE targeted assay is more sensitive than B1 targeted assay for this purpose.
KeywordsToxoplasma gondii Ocular toxoplasmosis Nested PCR RE gene B1 gene
The authors would like to express their gratitude to all lab staff of Cellular and Molecular Biology Research Center of Shahid Beheshti University of Medical Sciences for their contribution in the study and toxoplasmosis laboratory in Tehran University of Medical Sciences for preparation of the T. gondii (RH strain) tachyzoites.
This project is supported by Tehran University of Medical Science (Grant No: 29998-160-03-94).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
- 6.Carr J, Williams DG, Hayden RT (2010) Molecular detection of multiple respiratory viruses. In: Molecular diagnostics. Elsevier, Amsterdam, pp 289–300Google Scholar
- 12.Franzen C, Altfeld M, Hegener P, Hartmann P, Arendt G, Jablonowski H, Rockstroh J, Diehl V, Salzberger B, Fätkenheuer G (1997) Limited value of PCR for detection of Toxoplasma gondii in blood from human immunodeficiency virus-infected patients. J Clin Microbiol 35:2639–2641PubMedPubMedCentralGoogle Scholar
- 13.Furtado JM, Arruda S, Simões M, Garcia DM, Araújo M, Vieira B, Rodrigues MW, Smith J (2017) Clinical manifestations and visual prognosis of ocular toxoplasmosis. Investig Ophthalmol Vis Sci 58:2175Google Scholar
- 20.Previato M, Frederico FB, Murata F, Siqueira RC, Barbosa AP, Silveira-Carvalho AP, Meira C, Pereira-Chioccola VL, Gava R, Neto PM (2015) A Brazilian report using serological and molecular diagnosis to monitoring acute ocular toxoplasmosis. BMC Res Notes 8:746CrossRefPubMedPubMedCentralGoogle Scholar
- 25.Zurainee M, Abdullah KA, Fong M, Hoh H, Choon J, Rahmah N (2017) Ocular presentations and Toxoplasma serology. JUMMEC J Health Transl Med 5:98–102Google Scholar