Comparison of histopathology and PCR based assay for detection of experimentally induced toxoplasmosis in murine model

ABSTRACT

Objective: To compare histopathology and PCR based detection in diagnosis of experimentally induced toxoplasmosis of RH human strain of the parasite in murine models. Methods: A comparison of histopathology and PCR based detection was done to diagnose experimentally induced toxoplasmosis in ten inbred swiss albino mice after intraperitoneal inoculation of 100 tachyzoites of laboratory mantained human RH strain of the parasite. Tissue samples from lung, liver, spleen, brain, heart and kidney were taken and processed for histopathological examination while all the samples also were subjected to PCR, using primers directed to the multicopy of SAG 3 gene, in dublicates. Results: Histopathology revealed presence of tachyzoites only in liver while along with lung, liver, spleen and brain tissue yielded desired positive PCR amplicons. Conclusions: The SAG 3 based PCR is able to diagnose toxoplasmosis in those tissues which are declared negative by histopathological assay.