title: Boophilus microplus: the pattern of bovine immunoglobulin isotype responses to high and low tick infestations.
abstract: Cattle present variable levels of resistance to ticks and the immune correlates of these heritable phenotypes must be known in order to develop effective vaccines. The antibody responses to tick salivary antigens were examined in cattle of tick-susceptible (Holstein) and tick-resistant (Nelore) breeds. After heavy infestations, levels of IgG1 and IgG2 antibodies decreased in Holsteins and remained the same in Nelores. Conversely, levels of IgE antibodies increased in Holsteins. Different sizes of tick burdens modulated the IgG1 antibody response in a susceptible breed (Aberdeen): levels were higher than in controls in heavily infested animals, but not in those undergoing intermediary or minimal infestations. The three experimental groups presented similar levels of IgG2 antibodies. Levels of IgE antibodies were higher only in animals undergoing intermediate infestations. These results indicate that tick infestations suppress the IgG antibody response in susceptible breeds, that IgE antibodies are not protective, and that the dose of tick saliva modulates the isotype of host antibody responses.
authors.affiliation: Empresa Brasileira de Pesquisa Agropecuária--Embrapa, Brasília DF, Brazil.
authors.forename: Suely S
authors.initials: SS
authors.lastname: Kashino
authors.forename: Janaína
authors.initials: J
authors.lastname: Resende
authors.forename: Ana Maria S
authors.initials: AM
authors.lastname: Sacco
authors.forename: Clarisse
authors.initials: C
authors.lastname: Rocha
authors.forename: Laila
authors.initials: L
authors.lastname: Proença
authors.forename: Wanessa A
authors.initials: WA
authors.lastname: Carvalho
authors.forename: Alexandre A
authors.initials: AA
authors.lastname: Firmino
authors.forename: Rosevaldo
authors.initials: R
authors.lastname: Queiroz
authors.forename: Magda
authors.initials: M
authors.lastname: Benavides
authors.forename: Laurel J
authors.initials: LJ
authors.lastname: Gershwin
authors.forename: Isabel K F
authors.initials: IK
authors.lastname: De Miranda Santos
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology* / Q000469:parasitology; D004198:Disease Susceptibility / Q000276:immunology / Q000662:veterinary; D005260:Female; D007113:Immunity, Innate / Q000276:immunology; D007070:Immunoglobulin A / Q000096:biosynthesis / Q000097:blood; D007073:Immunoglobulin E / Q000096:biosynthesis / Q000097:blood; D007074:Immunoglobulin G / Q000096:biosynthesis* / Q000097:blood; D026863:Ixodidae / Q000276:immunology*; D008297:Male; D012463:Saliva / Q000276:immunology; D013984:Tick Infestations / Q000276:immunology / Q000469:parasitology / Q000662:veterinary*
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007073:Immunoglobulin E