Acellular pertussis vaccine based on outer membrane vesicles capable of conferring both long-lasting immunity and protection against different strain genotypes

GAILLARD ME; BOTTERO D; ERREA A; ORMAZABAL M; ZURITA E; MORENO G; RUMBO M; VAN DER LEY P; VAN DER ARK A; HOZBOR D

Dublin

Congreso; 10 th International Symposium on Bordetella; 2013

Trinity Biomedical Science Institute

To improve the pertussis disease control it seems to be necessary a new generation ofvaccines capable of conferring both long-lasting immunity and protection against differentBordetella genotypes. Previously we have demonstrated that the outer membrane vesicles (OMVs)obtained from B. pertussis are good vaccine candidates to protect against pertussis. Moreover,OMVs obtained from recombinant B. pertussis strain expressing PagL enzyme constitute a saferformulation (OMVsBpPagL), without altering protective immunity. In this work theOMVsBpPagL formulated with diphtheria and tetanus toxoids (TdapOMVsBpPagL) were used toevaluate its capacity to offer protection against the clinical isolate Bp106, selected asrepresentative of Argentinean circulating bacteria, and to induce long-term immunity. To theseaims, BALB/c mice were immunized with TdapOMVsBpPagL and challenged with sublethal doseof B. pertussis. Significant differences between TdapOMVsBpPagL immunized animals and thenegative control group were observed (p < 0.001). Comparisons with current commercial Tdapvaccine used at a dose in which pertussis toxin level was equivalent to thatof TdapOMVsBpPagL were performed. TdapOMVsBpPagL protected against the Argentinean clinicalisolate infection, whereas current commercial Tdap vaccine showed little protection against suchpathogen. The TdapOMVsBpPagL protective capacity persisted at least 9 months afterimmunization. The analysis of isotype distribution of the specific humoral response indicated thatTdapOMVsBpPagL induced Th1 and Th2 responses. In contrast, the currently licensed Tdap,induced a Th2 but a weak Th1 response. All results presented here showed thatTdapOMVsBpPagL is an interesting formulation to be considered for the development of novelacellular multi-antigen vaccine.Permission Yes