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Toxoplasmosis diagnosis predominantly relies on serology testing via enzyme-linked immunosorbent assay (ELISA), but these results are highly variable. Consequently, various antigens are being evaluated to improve the sensitivity and specificity of toxoplasmosis serological diagnosis. Here, we generated <i>Toxoplasma gondii</i> virus-like particles displaying AMA1 of <i>T. gondii</i> and evaluated their diagnostic potential. We found that AMA1 VLPs were highly sensitive and reacted with the sera acquired from mice infected with either <i>T. gondii</i> ME49 or RH strains. The overall IgG and IgM antibody responses elicited by AMA1 VLPs were substantially higher than those induced by the conventionally used <i>T. gondii</i> lysate antigen (TLA). Importantly, AMA1 VLPs were capable of detecting parasitic infection with <i>T. gondii</i> RH and ME49 as early as 1 week post-infection, even when mice were exposed to low infectious doses (5 × 10³ and 10 cysts, respectively). AMA1 VLPs also did not cross-react with the immune sera acquired from <i>Plasmodium berghei</i>-infected mice. Compared to TLA, stronger antibody responses were induced by AMA1 VLPs when tested using <i>T. gondii</i>-infected human sera. The sensitivities and specificities of the two antigens were substantially different, with AMA1 VLPs demonstrating over 90% sensitivity and specificity, whereas these values were in the 70% range for the TLA. These results indicated that AMA1 VLPs can detect infections of both <i>T. gondii</i> ME49 and RH at an early stage of infection caused by very low infection doses in mice, and these could be used for serological diagnosis of human toxoplasmosis.