Isolation of human monoclonal antibodies from 4CMenB vaccinees reveals PorB and LOS as the main OMV components inducing cross-strain protection [E. coli OMV]

In this study, we describe the development and use of an ad hoc protein microarray to characterize the target of HumAbs isolated from 4CMenB vaccinated subjects and induced by the OMV component of the vaccine A panel of 26 recombinant E. coli Outer Membrene Vesicles (hereafter called GMMA) expressing meningococcal antigens and two GMMA empty were printed randomly in replicates on a not-commercial protein microarray. All the proteins expressed in E.coli GMMA were 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 Human IgG and PBS + 40% glycerol spots.