Evaluation of Toxoplasma gondii recombinant proteins for the diagnosis of recently acquired toxoplasmosis by an immunoglobulin G analysis.

The value of T. gondii recombinant antigens rRop2, rGra4, rGra7 and rSAG1m (mature version) or rSAG1ct (C-terminal version) in differentiating recently acquired from chronic infections was determined by IgG-ELISA. The general highest sensitivity was observed with rRop2 whereas rSAG1m was not recognized by any of the serum samples, suggesting an incorrect folding. rGra4 and rGra7 showed significant higher sensitivity and absorbance values with serum samples from recently infected individuals compared to those with chronic infection. In contrast, rRop2 and rSAG1ct did not show differences in the reactivity pattern between both groups of serum samples.