Identification of Toxoplasma gondii antigens involved in the IgM AND IgG indirect hemagglutination tests for the diagnosis of toxoplasmosis

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Y.I. YAMAMOTO, V. HUBER, S. HOSHINO-SHIMIZU
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 1997
• Subjects: Toxoplasma gondii antigen; Hemagglutination test; Antibody absorption; Antibody elution; Immunoblot assay; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1590/S0036-46651997000300005; https://doaj.org/article/e427d33f66724f289ac7c3df8e87689a

Crude Toxoplasma gondii antigens represent raw material used to prepare reagents to be employed in different serologic tests for the diagnosis of toxoplasmosis, including the IgM and IgG indirect hemagglutination (IgG-HA and IgM-HA) tests. So far, the actual antigenic molecules of the parasite involved in the interaction with agglutinating anti-T. gondii antibodies in these tests are unknown. The absorption process of serum samples from toxoplasmosis patients with the IgG-HA reagent (G-toxo-HA) demonstrated that red cells from this reagent were coated with T. gondii antigens with Mr of 39, 35, 30, 27, 22 and 14 kDa. The immune-absorption process with the IgM-HA reagent (M-toxo-HA), in turn, provided antibody eluates which recognized antigenic bands of the parasite corresponding to Mr of 54, 35 and 30 kDa, implying that these antigens are coating red cells from this reagent. The identification of most relevant antigens for each type of HA reagent seems to be useful for the inspection of the raw antigenic material, as well as of reagent batches routinely produced. Moreover the present findings can be used to modify these reagents in order to improve the performance of HA tests for the diagnosis of toxoplasmosis Identificação de antígenos de Toxoplasma gondii envolvidos nas reações de hemaglutinação passiva IgM e IgG destinadas ao sorodiagnóstico da toxoplasmose Extratos brutos de Toxoplasma gondii constituem matéria prima antigênica para o preparo de reagentes empregados em diferentes testes sorológicos para o diagnóstico da toxoplasmose, incluindo entre estes as reações de hemaglutinação indireta para a detecção de anticorpos IgM (HA IgM) e IgG (HA IgG). Até o presente momento, moléculas antigênicas do parasita que realmente estão envolvidas na interação com anticorpos aglutinantes, anti-T. gondii, não são ainda bem conhecidas. O processo de absorção de soros de pacientes com toxoplasmose, utilizando o reagente de HA IgG (HA-toxo-G), possibilitou a demonstração de que hemácias deste reagente estavam ...