Application of PCR-ELISA method based on RE domain for diagnosis of toxoplasmosis in experimentally infected rat [Rattus norvegicus]

ABSTRACT

Toxoplasmosis may cause significant damage to the developing fetus and is as life-threatening opportunistic infection in immunocompromised persons. Molecular methods are known to be more sensitive and more specific than serological assays for diagnosis of toxoplasmosis. Application of quantitative PCR has evolved sensitive, specific, and rapid method for the detection of RH strain of Toxoplasma gondii DNA. In the present study, quantitative PCR-ELISA [Polymerase Chain Reaction- enzyme linked immunosorbent assay] was used for quantization of Taxoplasma gondii in the blood of 15 rats [Rattus norvegicus] infected experimentally with the parasite. In this regard Polymerase PCR - ELISA was developed for rapid detection of Toxoplasma gondii. DIG-labeled [digoxigenin-labeled] amplicons were hybridized with a specific biotinylated oligonucleotide probe in solution phase and subsequently transferred to streptavidin coated plates. The captured DNA-DNA hybrids were colorimetrically detected by the addition of anti-digoxigenin antibody peroxidase conjugate and substrate. DNA of Toxoplasma gondii were efficiently detected within 4 hours and no interference was encountered in the amplification and detection of the parasite. Efficiency of PCR-ELISA system was evaluated we found with several advantages in terms of sensitivity, rapidity and simplicity in this system