title: The use of lyophilized Schistosoma mansoni eggs as antigenic particles in a radioimmunoassay.
abstract: Lyophilized eggs of Schistosoma mansoni, when incubated briefly with serum from infected mice, bind antibodies, as made evident by subsequent binding of fluorescein labelled anti-IgG or 125I-labelled Protein A. On the basis of these findings, a radioimmunoassay was devised which employs whole lyophilized eggs (500 or 250 eggs/serum sample) as antigenic particles and 125I-labelled Protein A as a probe for antibody binding. Only 10 microliters of serum are required to obtain 90% of the maximal binding. Kinetic studies indicated that 70% of the maximal seropositivity develops in mice between five and six weeks after a light infection, reaches a maximum at eight weeks and fluctuates around a high plateau thereafter. Pre-incubation of the test serum with soluble egg antigen (SEA) considerably inhibits antibody binding to the eggs, suggesting that SEA-like antigens participate in the reaction.
mesh_terms: D000818:Animals; D000906:Antibodies / Q000032:analysis; D000941:Antigens / Q000276:immunology*; D005260:Female; D005455:Fluorescent Antibody Technique; D005612:Freeze Drying; D051379:Mice; D010063:Ovum / Q000276:immunology*; D011863:Radioimmunoassay / Q000379:methods*; D012550:Schistosoma mansoni / Q000276:immunology*; D012552:Schistosomiasis / Q000175:diagnosis*
chemical_list: D000906:Antibodies; D000941:Antigens