title: Correlation of antigen specific IgG and IgG(T) responses with Anoplocephala perfoliata infection intensity in the horse.
abstract: There is increasing interest in the application of serological methods to macro-parasite infections to indicate infection intensity, which in turn is related to pathogenicity. Colic is the single most important cause of mortality in horses and there is evidence that a proportion of colic cases are associated with infection with the intestinal cestode Anoplocephala perfoliata. In order to develop better tools to investigate this association, the correlation between antigen-specific equine IgG and IgG(T) and infection intensity of A. perfoliata was investigated. Affinity purification of a 12/13 kDa protein doublet from crude excretory/secretory (E/S) products, and its use in enzyme linked immunosorbent assays (ELISA) is described. Its use in the immunodiagnosis of equine cestodosis and the correlation of anti-12/13 kDa IgG and IgG(T) with parasite burden is investigated using sera from 94 horses of known tapeworm infection intensity. The anti-12/ 13 kDa IgG and IgG(T) ELISAs gave correlation coefficients with infection intensity of 0.56 and 0.63 respectively. Linear regression analysis also indicated that anti-12/ 13 kDa IgG(T) was the best predictor of infection intensity. The decay of anti-12/13 kDa IgG(T) in horses following the elimination of A. perfoliata is demonstrated for four horses. Specificity of the anti-12/13 kDa IgG(T) ELISA is investigated with sera from 33 A. perfoliata negative horses with other helminth infections. Immunoblotting studies demonstrate no cross-reactivity between A. perfoliata 12/13 kDa antigen and the protein antigens of other helminths. It is concluded that assay of anti-12/13 kDa IgG(T) provides a useful tool for the assessment of A perfoliata infection intensity for clinical diagnosis and for epidemiological studies.
authors.affiliation: Liverpool School of Tropical Medicine/Faculty of Veterinary Science.
authors.forename: C J
authors.initials: CJ
authors.lastname: Proudman
authors.forename: A J
authors.initials: AJ
authors.lastname: Trees
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000918:Antibody Specificity; D000947:Antigens, Helminth / Q000737:chemistry / Q000302:isolation & purification; D002589:Cestoda / Q000276:immunology*; D002590:Cestode Infections / Q000276:immunology / Q000662:veterinary*; D015801:Helminth Proteins / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification; D006734:Horse Diseases / Q000276:immunology*; D006736:Horses; D007074:Immunoglobulin G / Q000097:blood
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015801:Helminth Proteins; D007074:Immunoglobulin G