Early adaptive immune responses in the respiratory tract of foot and mouth disease-infected cattle

PEGA, JUAN; BUCAFUSCO, DANILO; DI GIACOMO, SEBASTIÁN; SCHAMMAS, JUAN MANUEL; MALACARI, DARIO; CAPOZZO, ALEJANDRA; ARZT, JONATHAN; PÉREZ-BEASCOECHEA, CLAUDIA; MARADEI, EDUARDO; RODRÍGUEZ, LUIS; BORCA, MANUEL VÍCTOR; PÉREZ FILGUEIRA, MARIANO

JOURNAL OF VIROLOGY

AMER SOC MICROBIOLOGY

Lugar: Washington; Año: 2013 vol. 87 p. 2489 - 2495

0022-538X

Foot and mouth disease (FMD) is a highly contagious viral disease which affects both domestic and wildlife biungulate species. This acute disease, caused by the FMD virus (FMDV), usually includes an active replication phase in the respiratory tract up to 72 h post-infection followed by hematogenous dissemination and vesicular lesions at oral and foot epithelia. The role of the early host local adaptive immunity in the outcome of the infection is not well understood. Here we report the kinetics of appearance of FMDV-specific antibody-secreting cells (ASC) in lymphoid organs along the respiratory tract and spleen in cattle infected by aerosol exposure. While no responses were observed up to 3 days post-infection (dpi), all animals developed FMDV-ASC in all the lymphoid organs studied at 4 dpi. Tracheobronchial lymph nodes were the most reactive organs at this time and IgM was the predominant isotype, followed by IgG1. Numbers of FMDVASC further augmented at 5 and 6 dpi with an increasing prevalence in upper respiratory organs. Systemic antibody responses were slightly delayed compared with the local reaction. Also, IgM was the dominant isotype in serum at 5 dpi, coinciding with a sharp decrease of viral RNA detection in peripheral blood. These results indicate that following aerogenous administration, cattle developed a rapid and vigorous genuine local antibody response throughout the respiratory tract. Time course and isotype profiles would indicate the presence of an efficient T-independent antibody response which drives the IgM-mediated virus clearance in cattle infected by FMDV aerosol exposure.