Seroreactivity to and avidity for recombinant antigens in toxoplasmosis.

To improve serodiagnostic methods for the diagnosis of acute toxoplasmosis during pregnancy, a new test system has been developed and evaluated based on the use of recombinant antigens. Five recombinant Toxoplasma gondii antigens (ROP1, MAG1, SAG1, GRA7, and GRA8) were cloned in Escherichia coli, purified, and applied directly onto nitrocellulose membranes in a line assay (recomLine Toxoplasma). A panel of 102 sera from 25 pregnant women with supposed recent toxoplasmosis and from two symptomatic children was compared to a panel of 71 sera from individuals with past infection.