03751naa a2200313 a 450000100080000000500110000800800410001902200140006002400390007410000140011324501500012726000090027750008360028652019540112265300160307665300160309265300160310865300220312465300560314665300210320270000170322370000200324070000160326070000140327670000140329070000180330470000150332277301000333710644742024-02-26       2024    bl uuuu     u00u1 u    #d  a0264-410X7 a10.1016/j.vaccine.2023.12.0672DOI1 aCOSTA, M.  aFasciola hepatica infection modifies lgG1 specific immune response to foot-and-mouth disease virus induced by vaccination.h[electronic resource]  c2024  aArticle history: Received 19 August 2023; Received in revised form 15 December 2023; Accepted 20 December 2023; Available online 6 January 2024. -- Correspondence: Freire, T.; UdelaR, Facultad de Medicina, Departamento de Inmunobiología, Gral. Flores 2125, Montevideo, Uruguay; email:tfreire@fmed.edu.uy  -- Funding: Financial supports were provided by Programa de Desarrollo de Ciencias Básicas ( PEDECIBA ), Comisión Sectorial de Investigación Científica and Agencia Nacional de Investigación e Innovación (SNI-ANII and FCE_1_2019_1_156295) to Teresa Freire. Funding by GFRA Research to Florencia Mansilla was also provided. M. Costa was funded by ANII and CAP. A. V. Capozzo is a researcher of CONICET , Argentina. -- Supplementary data to this article can be found online at https://doi.org/10.1016/j.vaccine.2023.12.067  aABSTRACT.- Fasciola hepatica, a worldwide distributed helminth, has a robust immunoregulatory effect in the host, increasing the susceptibility to secondary infections. Foot and mouth disease (FMD) is a highly contagious acute vesicular viral disease effectively controlled by vaccination in endemic regions. Despite the evidence of immunoregulatory effects, the impact of fasciolosis on the immune response induced by FMD vaccination in cattle has never been assessed. Our objective was to evaluate whether the infection by F. hepatica in cattle influences the long-term immunity elicited by the currently used commercial FMD-inactivated vaccines. Aberdeen Angus steers negative for F. hepatica were vaccinated twice against FMD virus (FMDV) during the first 6 months of age using a commercial oil vaccine formulated with A24/Cruzeiro and O1/Campos strains. When maternal antibodies against F. hepatica were weaned (18--20 months of age) animals were divided into groups of 12 and infected or mock-infected with 500 metacercariae/animal. Individual serum samples were collected at 0-, 28-, 59-, 87- and 157-days post-infection (dpi). Indirect ELISAs were used to detect A24/Cruzeiro specific bovine IgG and IgG subtypes. The total IgG antibody levels and avidity against FMDV did not show significant differences between all the groups. The commercial vaccine induced higher IgG2 than IgG1 titers in vaccinated animals. Anti-FMDV IgG1 levels significantly decreased in the infected group at 28 dpi. In addition, the avidity of IgG1 FMDV-specific antibodies at day 28 in the infected group was reduced compared to the control. These results show that F. hepatica infection modified anamnestic responses against FMDV, reducing serum IgG1 titers and avidity. To our knowledge, this is the first report of immune-regulation of F. hepatica altering the immune response of FMD vaccines, one of the most globally used animal vaccines. © 2024 Elsevier Ltd  aFasciolosis  aFMD vaccine  aIgG avidity  aImmune modulation  aPLATAFORMA DE INVESTIGACIÓN EN SALUD ANIMAL - INIA  aVaccine efficacy1 aMANSILLA, F.1 aMANUEL SALA, J.1 aSARAVIA, A.1 aUBIOS, D.1 aLORES, P.1 aCAPOZZO, A.V.1 aFREIRE, T.  tVaccine. 2024, Volume 42, Issue 3, Pages 541-547. https://doi.org/10.1016/j.vaccine.2023.12.067