title: Lawsonia intracellularis-specific interferon γ gene expression by peripheral blood mononuclear cells in vaccinated and naturally infected foals.
abstract: The cell-mediated immune response to Lawsonia intracellularis, the agent of equine proliferative enteropathy (EPE), was investigated in vaccinated and naturally infected foals. Interferon (IFN)-γ gene expression was determined in peripheral blood mononuclear cells collected from vaccinated (n=6) and control foals (n=6) every 30 days for 180 days following first vaccine administration, and from clinically affected foals (n=16) within 7-10 days of diagnosing EPE. Seroconversion (immunoperoxidase monolayer assay titer ≥60) occurred in 5/6 vaccinated foals between 60 and 90 days following the first vaccine administration and these foals remained seropositive for the remaining study period. IFN-γ gene expression in all vaccinated foals was significantly higher (P<0.05) on days 60-180 following first vaccine administration compared to IFN-γ gene expression in control foals. When IFN-γ gene transcription was compared between naturally infected and vaccinated foals, a significant difference (P<0.05) was observed only for day 0.
authors.affiliation: Department of Veterinary Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA. npusterla@ucdavis.edu
authors.forename: Nicola
authors.initials: N
authors.lastname: Pusterla
authors.forename: Samantha
authors.initials: S
authors.lastname: Mapes
authors.forename: Connie
authors.initials: C
authors.lastname: Gebhart
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines / Q000008:administration & dosage*; D016022:Case-Control Studies; D045824:Desulfovibrionaceae Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D015870:Gene Expression; D006734:Horse Diseases / Q000276:immunology* / Q000517:prevention & control; D006736:Horses; D007111:Immunity, Cellular / Q000276:immunology*; D007371:Interferon-gamma / Q000235:genetics*; D020639:Lawsonia Bacteria / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D013997:Time Factors
chemical_list: D001428:Bacterial Vaccines; D007371:Interferon-gamma