Article

High levels of IgG4 to Schistosoma mansoni egg antigens in individuals with periportal fibrosis

Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal Minas Gerais, Belo Horizonte, Brazil.
The American journal of tropical medicine and hygiene (Impact Factor: 2.7). 06/2002; 66(5):542-9.
Source: PubMed

ABSTRACT

Specific IgG4 and IgE responses to adult worm antigen and soluble egg antigen (SEA) were examined in 267 individuals from an area in which schistosomiasis mansoni is endemic. Based on information obtained from clinical and sonographic examinations of this sample, the individuals were divided in three groups: 1) 204 individuals without periportal fibrosis, and liver and spleen enlargements; 2) 41 individuals without periportal fibrosis, but presenting with organopathy, with or without organomegaly; and 3) 22 individuals with periportal fibrosis, regardless of their status as having hepatomegaly and/or splenomegaly. Levels of IgG4 to SEA were significantly higher in sera from patients with fibrosis compared with the patients from the other two groups. We also found significantly higher levels of IgG4 against SEA in egg-negative patients with fibrosis compared with egg-negative patients from the other two groups. This report demonstrates a specific humoral response in patients presenting with initial fibrosis, a form of schistosomiasis transient between intestinal and severe hepatosplenic.

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Available from: Jeffrey Bethony, Jun 27, 2014
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    • "Similarly, Bonnard et al. [29] reported that higher levels of IgG4 and IgA against SEA antigens were found in patients with severe schistosomiasis. Moreover, the authors [28], [29] also showed no association between IgE responsiveness measured by direct ELISA against SEA antigens and disease severity. We demonstrated that IgG responsiveness to the S. mansoni antigens, SEA and SWAP, is also positively associated with severe forms of schistosomiasis, defined by clinical examination and by ultrasound measurement. "
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    • "Moreover, resistance to infection has also been associated with high levels of IgE against crude adult antigen extracts from adult worm (SWAP) (Vereecken et al., 2007). Interestingly, reinfection may occur when elevated levels of IgG4 subclass anti-SWAP are observed (Correa-Oliveira et al., 2000; Hagan et al., 1987; Silveira et al., 2002). Although the Schistosomaspecific IgE levels were not measured in the current work, it is likely that increased total IgE levels may partially reflect a specific antiparasite antibody response. "
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