title: Serotyping of Toxoplasma gondii infections in humans using synthetic peptides.
abstract: To determine whether the characteristics of disease due to Toxoplasma gondii (toxoplasmosis) are dependent on the infecting strain, we have developed an enzyme-linked immunosorbent assay for typing strains that uses infection serum reacted against polymorphic peptides derived from Toxoplasma antigens SAG2A, GRA3, GRA6, and GRA7. Pilot studies with infected mice established the validity of the approach, which was then tested with human serum. In 8 patients who had Sabin-Feldman dye test titers >64 and for whom the infecting strain type was known, the peptides correctly distinguished type II from non-type II infections. ELISA analysis of a second group of 10 infected pregnant women from whom the parasite strain had not been isolated gave a clear prediction of the strain type causing infection. This method should allow statistically significant data to be obtained about whether different strain types cause disease with different characteristics.
authors.affiliation: Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA.
authors.forename: Jiang-Ti
authors.initials: JT
authors.lastname: Kong
authors.forename: Michael E
authors.initials: ME
authors.lastname: Grigg
authors.forename: Lyle
authors.initials: L
authors.lastname: Uyetake
authors.forename: Stephen
authors.initials: S
authors.lastname: Parmley
authors.forename: John C
authors.initials: JC
authors.lastname: Boothroyd
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D000953:Antigens, Protozoan / Q000737:chemistry / Q000276:immunology; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000276:immunology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012703:Serotyping / Q000379:methods*; D014122:Toxoplasma / Q000145:classification* / Q000276:immunology / Q000302:isolation & purification*; D014123:Toxoplasmosis / Q000175:diagnosis* / Q000276:immunology*
chemical_list: D000953:Antigens, Protozoan; D010455:Peptides