A test is described for the detection oflgM anti-toxoplasma antibodies based on the technique of serum IgM capture by anti-IgM antibodies adsorbed to plasticplates. A suspension of formolized human erythrocytes, sensitized with Toxoplasma gondii antigens is then used as a indicative of anti-toxoplasma specificity of the captured antibodies. The use of sensitized red-cells instead of parasite suspensions, as previously described by Desmonts et al., 1981, results in a more practical test. Adequate red cells suspensions are easily prepared just by diluting the usual toxoplasmosis hemagglutination reagent and reading the test is much facilitated with red cells as indicator than with the colorlessparasites, with clear- cut results. The test was comparable in sensitivity to the IgM-immunofluorescence test, but with no inteiference of rheumatoid factor or competition oflgG antibodies.
Toxoplasmosis; Immunodiagnosis; IgM