title: The effects of endoparasitism on the immune response to orally administered antigen in cats.
abstract: The aim of the study was to assess whether infection with Toxocara cati (T. cati) facilitates the induction of immunoglobulin (Ig) E or other antibody responses to a specific antigen administered with food in kittens. Two groups of 10 cats each, either experimentally infected with T. cati or parasite-free, were dosed with human serum albumin (HSA) added daily to their food from day 7 to 28 inclusive. Levels of HSA-specific IgE, IgG, IgA and IgM were assessed in the serum by enzyme-linked immunosorbent assay (ELISA) in both groups of cats at weeks 0, 2, 4 and 8. Although weak, an IgE response was detected in most of the cats 1 week after exposure to HSA. However, HSA-specific IgG and IgA could only be detected from the third week after exposure to HSA. The group of parasitized cats had significantly higher levels of HSA-specific antibodies of the IgG and IgA at weeks 4 and 8 (p<0.05 by Mann-Whitney) and IgE isotypes at weeks 2 and 4 (p<0.05 by analysis of variance (ANOVA)) than did the group of parasite-free cats. Specific IgM antibody was not detected in the sera of any of the 20 cats. These findings are supportive of a role of T. cati infection in enhancing the IgE response to orally administered antigens, and hence possibly, in genetically susceptible individuals, in the development of food hypersensitivity.
authors.affiliation: University of Edinburgh, Royal (Dick) School of Veterinary Studies, Department of Veterinary Clinical Studies, Easter Bush Veterinary Centre, Roslin, Midlothian EH25 9RG, UK. gilbe125@umn.edu
authors.forename: S
authors.initials: S
authors.lastname: Gilbert
authors.forename: R E W
authors.initials: RE
authors.lastname: Halliwell
mesh_terms: D000818:Animals; D000906:Antibodies / Q000097:blood*; D002371:Cat Diseases / Q000276:immunology* / Q000469:parasitology; D002415:Cats; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology / Q000662:veterinary; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D012709:Serum Albumin / Q000276:immunology*; D014120:Toxocariasis / Q000276:immunology*
chemical_list: D000906:Antibodies; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D012709:Serum Albumin