title: Indirect immunofluorescence in toxoplasmosis: frequency, nature and specificity of polar staining.
abstract: In the indirect immunofluorescence test ant the Remington test for Toxoplasmosis of some sera, a polar fluorescence of the parasite has been observed. This "Polar Factor" is not observed in umbilical cord blood and in sera of children less than 6 months old, but has a relative high frequency in sera of adults. The detection of the factor depends on the nature of the used antigen. With sucrose gradient centrifugation, anti-IgM immunofluorescence, 2-mercaptoethanol-treatment and selective adsorption of sera, we could demonstrate that this factor is a non-specific IgM.
mesh_terms: D005189:False Positive Reactions; D005455:Fluorescent Antibody Technique; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis; D008722:Methods; D014123:Toxoplasmosis / Q000175:diagnosis*
chemical_list: D007075:Immunoglobulin M