ARTICLE OPEN OpcA and PorB are novel bactericidal antigens of the 4CMenB vaccine in mice and humans

In this study, we describe the development and use of an ad hoc protein microarray to study the immune response induced by the OMV component of 4CMenB vaccine in mouse sera before and after immunization. A panel of 26 recombinant E. coli Outer Membrane Vesicles (hereafter called GMMA) expressing meningococcal antigens, two GMMA empty, OMV from NZ98/254 and the major recombinant proteins of 4CMenB (NadA, GNA2091-fHbp and NHBA-GNA1030) were printed randomly in replicates on a non-commercial protein microarray. With the expection of NadA, GNA2091-fHbp and NHBA-GNA1030, all the proteins expressed in E.coli GMMA were e FLAG- and His-tagged fusions. Recombinant GMMA were obtained from the supernatant of a late-exponential growth of E. coli. The supernatants were subjected to high-speed centrifugation and the pellets containing the GMMA were washed with PBS. Controls consisted of 8 serial 2-fold dilutions of mouse IgG and PBS + 40% glycerol spots. Sera were profiled for anti-Mouse IgG specific analysis of reactivity to the spotted proteins.