anti-toxoplasma activity of 2-(naphthalene-2-γlthiol)-1h indole.

background: this study was undertaken to evaluate the viability, infectivity and immunity of toxoplasma gondii tachyzoites exposed to 2-(naphthalene-2-ylthio)-1h-indole.   methods : tachyzoites of rh strain were incubated in various concentrations of 2- (naphthalene-2-ylthio)-1h-indole (25-800μm) for 1.5 hours. then, they were stained by pi and analyzed by fluorescence-activated cell sorting (facs). to eval-uate the infectivity, the tachyzoites exposed to the different concentrations of the compound were inoculated to 10 balb/c mice groups. for control, parasites ex-posed to dmso (0.2% v/v) were also intraperitoneally inoculated into two groups of mice. the immunity of the exposed tachyzoites was evaluated by inoculation of the naïve parasite to the survived mice. results : the ld50 of 2-(naphthalene-2-ylthio)-1h-indole was 57 μmol. the lon-gevity of mice was dose dependent. five mice out of group 400μmol and 3 out of group 800μmol showed immunization to the parasite.   conclusion : our findings demonstrated the toxoplasmocidal activity of the com-pound. the presence of a well-organized transporter mechanism for indole com-pounds within the parasite in conjunction with several effective mechanisms of these compounds on toxoplasma viability would open a window for production of new drugs and vaccines.