Genetic and immunologic characterization of a novel serotype 4, 15 strain of Neisseria meningitidis

The porin proteins of Neisseria meningitidis are important components of ou ter membrane protein (OMP) vaccines. The class 3 porin gene, porB, of a nov el serogroup B, serotype 3, 15 isolate from Chile (Ch501) was found to be V R1-4, VR2-15, VR3-15 and VR4-15 by pol B variable region (VR) typing. Rabbi t immunization studies using outer membrane vesicles revealed immunodominan ce of individual PorB (class 3) VR epitopes, The predominant anti-Ch501 Por B response was directed to the VRI epitope. Anti-PorB VR1 mediated killing was suggested by the bactericidal activity of Ch501 anti-sera against a typ e 4 strain not expressing PorA or class 5 OMPs. Studies that examine the mo lecular epidemiology of individual porB VRs, and the immune responses to Po rB epitopes, may contribute co the development of broadly protective group B meningococcal vaccines. (C) 2000 Federation of European Microbiological S ocieties. Published by Elsevier Science B.V. All rights reserved.