Characterization of the key antigenic components of pertussis vaccine based on outer membrane vesicles.

ORMAZABAL MAXIMILIANO; BARTEL ERIKA; GAILLARD MARÍA EMILIA; BOTTERO DANIELA; ERREA AGUSTINA; ZURITA MARÍA EUGENIA; MORENO GRISELDA; RUMBO MARTÍN; CASTUMA CELINA; FLORES DARÍO; DANIELA HOZBOR

VACCINE

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2014

0264-410X

Pertussis, a respiratory preventable vaccine disease, has been resurged during the last two decades in different countries. In particular since 2010 to 2013 large outbreaks were detected in US, Australia, UK and The Netherlands with significant mortality in infants. Possible causes for the resurgence of pertussis include waning immunity, the switch from whole cell vaccines to less effective acellular vaccines (aP) and pathogen adaptation. The epidemiological situation of pertussis point out the need to develop new vaccines and in this sense previously we developed a new vaccine based on Outer Membrane Vesicle (OMV) which have been shown to be safe and induce protection in mice. Here, we have further investigated the properties of OMV vaccines; in particular we investigated the contribution of PTx and Prn in OMVs-mediated protection against pertussis. A PTx-deficient OMVs and Prn-deficient OMVs were obtained from defective B. pertussis mutants. The absence of PTx or Prn did compromise the protective capacity of the OMVs formulated as Tdap vaccine. In vivo, whereas the protective efficacy of the PTx-deficient OMVs in mice was comparable to Prn-deficient OMVs, the protective capacitive of both deficient OMVs was significantly impaired when it was compared with the wild type OMVs. Interesting, using OMVs obtained from B. pertussis strain which does not express any of the virulence factors but express the avirulent phenotype; we observed that the protective ability of such OMVs was lower than that of OMVs obtained from virulent B. pertussis phase. However, it was surprising that although the protective capacity of avirulent OMVs was lower, they were still protective in the used mice model. These results allow us to hypothesize that OMVs from avirulent phase shares protective components with all OMVs assayed. Using immune proteomic strategy we identified some common components could play an important role in protection against pertussis.