title: The detection of autoantibodies to IgE in plasma of individuals infected with hookworm (Necator americanus) and the demonstration of a predominant IgG1 anti-IgE autoantibody response.
abstract: In this study we have demonstrated significantly elevated levels of circulating IgG autoanti-IgE antibody in hookworm infected individuals from Kebasob village on Karkar Island, Papua New Guinea. Although anti-IgE activity was demonstrable in IgG1, IgG3 and IgG4, IgG1 was by far the most important subclass of IgG anti-IgE in terms of frequency of detection (34/39; 87.2%) and magnitude of increase (P = 0.0000); with IgG3 (16/39; 41.0%) and IgG4 (15/39; 38.5%) antibodies being considerably less prevalent. Plasma levels of IgG1 anti-IgE (P = 0.0019) and IgG3 anti-IgE (P = 0.0034) showed significant correlations with total IgE concentrations, but not with IgE specific to excretory-secretory worm products; thus suggesting that anti-IgE synthesis is more related to polyclonal hyper IgE production than to antigen-specific IgE stimulation. No correlation was seen between IgG subclass anti-IgE levels and faecal egg counts or worm burden. Given that our data failed to show a negative or a positive correlation between anti-IgE and the degree of infection with hookworm, it is tempting to speculate that the main role of autoanti-IgE is to provide the host with protection against immune complex- and IgE-mediated hypersensitivity reactions to parasitic antigens.
authors.affiliation: Department of Immunology, University of Nottingham, UK.
authors.forename: F
authors.initials: F
authors.lastname: Shakib
authors.forename: D I
authors.initials: DI
authors.lastname: Pritchard
authors.forename: E A
authors.initials: EA
authors.lastname: Walsh
authors.forename: S J
authors.initials: SJ
authors.lastname: Smith
authors.forename: A
authors.initials: A
authors.lastname: Powell-Richards
authors.forename: S
authors.initials: S
authors.lastname: Kumar
authors.forename: P
authors.initials: P
authors.lastname: Edmonds
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000909:Antibodies, Helminth / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology*; D007074:Immunoglobulin G / Q000096:biosynthesis*; D008297:Male; D008875:Middle Aged; D017221:Necator americanus / Q000276:immunology*; D009332:Necatoriasis / Q000276:immunology*; D017455:Receptors, IgE / Q000276:immunology
chemical_list: D000909:Antibodies, Helminth; D001323:Autoantibodies; D007074:Immunoglobulin G; D017455:Receptors, IgE; D007073:Immunoglobulin E