Identification of Live Toxoplasma gondii by the NASBA method in Rat

Authors
1 Department of Parasitology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
2 Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
3 Associated Professor, Department of Parasitilogy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Abstract
Objective: Toxoplasmosis is a worldwide disease, for which different detection methods have been used. The nucleic acid sequence-based amplification (NASBA) method is shown to be highly efficient for diagnosis of live microorganisms. The present research evaluates the molecular isothermal method of NASBA to identify live Toxoplasma gondii (T. gondii) in rat.
Methods: Tachyzoites of T. gondii were inoculated in the peritoneal cavities of mice (Mus musculus) and their RNA was extracted. The NASBA method was then used to amplify the tachyzoite B1 rRNA gene. Next, we examined blood samples from 30 experimentally infected case and control rats (Rattus norvegicus) by NASBA. Finally, the resultant band was investigated on an agarose gel.
Results: The B1 genes extracted from both the tachyzoites and blood samples were successfully amplified by the NASBA method. This amplified gene yielded an amplicon of approximately 116 bp on gel agarose.
Conclusion: NASBA is highly efficient for the identification of live T. gondii. This method can be applied for early diagnosis of active toxoplasmosis in both newborns and immunocompromised individuals.

Keywords


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