VirB7 PROTEIN FROM Brucella abortus AS A VACCINE CANDIDATE IN A MURINE MODEL

FLORENCIA MUÑOZ GONZALEZ; IVÁN ALONSO PAIVA; FALIVENE, JULIANA; FOCARACCIO JULIETA; BALDI, PABLO; FERRERO MARIANA CRISTINA

Banff, Alberta

Simposio; Keystone Symposia Emerging Technologies in Vaccine Discovery and developmente; 2018

Keystone Symposia

Brucella spp. can be transmitted to humans through mucosae. Currently, there are no human vaccines against this infection. Using a murine model, we evaluated VirB7, a virulence factor from Brucella, as a potential component of an acellular vaccine against brucellosis.Six-week-old Balb/c mice received 3 weekly intranasal doses of either VirB7 (10 µg) plus 3?,5?-c-di-AMP (c-di-AMP,10ug), c-di-AMP alone or saline. One week after the last dose serum samples were obtained and lungs, spleen and cervical lymph nodes were processed. Cells obtained from these tissues were cultured in the presence of VirB7 (1 ug or 10 ug) or RPMI (negative control). After 24h lymph node cells were harvested and stained with anti-CD3, anti-CD4, anti-CD8, anti-CD44 and anti-CD62L antibodies for flow cytometry analysis. In vitro production of gamma interferon (IFN-γ) by lung cells, and IFN-γ, interleukin-5 (IL-5) and IL-2 by spleen cells was determined after 72 h of stimulation. Other mice from the immunized (VirB7/c-di-AMP) and adjuvant groups were injected intradermally in opposite footpads with VirB7 or saline to evaluate DTH (48 and 72 h).In response to VirB7, splenocytes from immunized mice increased their secretion of IFN-γ (mean: 1949 pg/ml and 5662 pg/ml for 1 ug and 10 µg VirB7, respectively; p