title: Immunological response and markers of cell damage in seropositive horses for Toxoplasma gondii.
abstract: Toxoplasmosis is an important parasitic disease affecting several species of mammals, but little is known about this disease in horses. This study aimed to investigate the levels of several immunological variables and markers of cell damage in the serum of seropositive horses for Toxoplasma gondii. Sera samples of adult horses from the Santa Catarina State, Brazil used on a previous study were divided into groups according to their antibody levels for T. gondii determined by immunofluorescence assay, i.e. 20 samples from seronegative horses (Group A - control), 20 samples from horses with titers of 1:64 (Group B), 20 samples of horses with titers of 1:256 (Group C), and five samples from horses with titers of 1:1024 (Group D). Positive animals (Groups B, C, and D) had higher levels of immunoglobulins (IgM and IgG), pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1, IL-4, and IL-6) and protein C-reactive protein, as well as lower levels of IL-10 (anti-inflammatory cytokine) when compared to seronegative horses (Group A). The nitric oxide levels were also elevated in seropositive horses. Therefore, we have found humoral and cellular immune responses in seropositive horses, and a correlation between high antibody levels and inflammatory mediators. Markers of cell injury by lipid peroxidation (TBARS) and protein oxidation (AOPP) were elevated in animals seropositives for T. gondii when compared to seronegatives. Therefore, seropositive horses to T. gondii can keep active immune responses against the parasite. As a consequence with chronicity of disease, they show cellular lesions that may lead to tissue damage with the appearance of clinical disease.
authors.affiliation: Postgraduate Program of Nanoscience, Centro Universitário Franciscano, Santa Maria, RS, Brazil.
authors.forename: Guilherme M
authors.initials: GM
authors.lastname: Do Carmo
authors.affiliation: Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil. Electronic address: aleksandro_ss@yahoo.com.br.
authors.forename: Aleksandro S
authors.initials: AS
authors.lastname: Da Silva
authors.affiliation: Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil.
authors.forename: Vanderlei
authors.initials: V
authors.lastname: Klauck
authors.affiliation: Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil.
authors.forename: Rafael
authors.initials: R
authors.lastname: Pazinato
authors.affiliation: Department of Veterinary Medicine, UDESC, Lages, SC, Brazil.
authors.forename: Anderson B
authors.initials: AB
authors.lastname: Moura
authors.affiliation: Postgraduate Program in Pharmacology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil.
authors.forename: Thiago
authors.initials: T
authors.lastname: Duarte
authors.affiliation: Universidade Luterana do Brasil, Santa Maria, RS, Brazil.
authors.forename: Marta M M F
authors.initials: MM
authors.lastname: Duarte
authors.affiliation: Postgraduate Program in Pharmacology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil; Research Laboratory of Clinical Biochemistry, Department of Clinical and Toxicological Analysis, UFSM, Santa Maria, RS, Brazil.
authors.forename: Guilherme V
authors.initials: GV
authors.lastname: Bochi
authors.affiliation: Postgraduate Program in Pharmacology, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil; Research Laboratory of Clinical Biochemistry, Department of Clinical and Toxicological Analysis, UFSM, Santa Maria, RS, Brazil.
authors.forename: Rafael N
authors.initials: RN
authors.lastname: Moresco
authors.affiliation: Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil.
authors.forename: Lenita M
authors.initials: LM
authors.lastname: Stefani
mesh_terms: D062107:Advanced Oxidation Protein Products / Q000032:analysis; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000276:immunology; D001938:Brazil; D002097:C-Reactive Protein / Q000032:analysis; D016207:Cytokines / Q000378:metabolism; D006734:Horse Diseases / Q000276:immunology* / Q000469:parasitology; D006736:Horses; D007111:Immunity, Cellular; D015227:Lipid Peroxidation; D014122:Toxoplasma / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000276:immunology*
chemical_list: D062107:Advanced Oxidation Protein Products; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016207:Cytokines; D002097:C-Reactive Protein
keywords: Cytokines; Horses; Immunoglobulin; Toxoplasmosis