An innovative mucosal vaccine based on BtaF adhesin from Brucella suis

SYCZ, G; ZORREGUIETA, A; MUÑOZ GONZALEZ, F; BALDI, PC; ALONSO PAIVA, I; FERRERO, MC

Mar del Plata

Congreso; LXVI Reunión Anual de la Sociedad Argentina de Inmunología; 2018

Sociedad Argentina de Inmunología

Currently, there are no human or porcine vaccines against Brucella infection, which is mainly transmitted through mucosae. We have shown that the BtaF adhesin is necessary for full virulence of B. suis after intragastric and respiratory murine infection. Here we characterized the cellular immune response elicited after intranasal immunization and its potential protectivity against brucellosis.Six-week-old Balb/c mice were weekly immunized for 3 weeks with BtaF (10ug) plus c-di-AMP (10ug), c-di-AMP alone or saline.One week after last immunization lungs and cervical lymph nodes were harvested, and the cells obtained were cultured in the presence of BtaF (10ug) or RPMI. After 24h lymph node cells were stained with anti-CD3, anti-CD4, anti-CD8, anti-CD44 and anti-CD62L antibodies for flow cytometry analysis. In vitro production of IFN-γ by lung cells was determined after 72h of stimulation. Other mice from the immunized and saline groups were injected intradermally in opposite footpads with BtaF or saline to evaluate DTH (48 and 72h). Two weeks after last immunization Balb/c mice were challenged with B. suis through the intragastric or intratracheal route. CFU counts were determined in lungs, liver and spleens 20 days after challenge.Pulmonary cells from immunized mice secreted high levels of IFN-γ after stimulation with BtaF (mean: 8651pg/ml, p