Specificity of human bactericidal antibodies against PorA P1.7,16 induced with a hexavalent meningococcal outer membrane vesicle vaccine.

Journal Article (Clinical Trial;Journal Article)

A set of isogenic strains was constructed from the meningococcal reference strain H44/76 (B:15:P1.7,16) which differed only in their outer membrane protein (OMP) compositions. First, three isogenic strains lacking the expression of either class 3 (PorB) or class 4 (RmpM) OMP or both were obtained. Second, three isogenic class 1 OMP loop-deficient strains of H44/76 lacking the predicted loop 1 or 4 or both of class 1 OMP (PorA) were obtained. Third, three isogenic class 1 OMP strains which differed by point mutations in the predicted loop 4 of subtype P1.16 were constructed. Strains were constructed through transformation with gene constructs made in Escherichia coli and their homologous recombination into the meningococcal chromosome. This study describes the contribution of one of the six class 1 OMPs, PorA P1.7,16, in the development of bactericidal antibodies after a single immunization of adult volunteers with 50 or 100 micrograms of protein within a hexavalent PorA outer membrane vesicle vaccine. PorA-, PorB-, and RpmM-deficient isogenic strains were used to define the human immune response against PorA. The loop-deficient isogenic strains were used to define the contribution of loops 1 and 4 of PorA in the development of bactericidal anti-PorA antibodies. The isogenic strains carrying a point mutation in loop 4 were used to study the cross-reactivity of the induced bactericidal antibodies against target strains showing microheterogeneity. The results indicate that a single immunization with the hexavalent PorA vaccine induced a dose-dependent bactericidal immune response, which is directed mainly against PorA. The epitope specificity of antibodies is directed mostly against loop 1, although loop 4 and as-yet-unidentified epitopes of PorA P1.7,16 are also involved.

Full Text

Duke Authors

Cited Authors

  • van der Voort, ER; van der Ley, P; van der Biezen, J; George, S; Tunnela, O; van Dijken, H; Kuipers, B; Poolman, J

Published Date

  • July 1996

Published In

Volume / Issue

  • 64 / 7

Start / End Page

  • 2745 - 2751

PubMed ID

  • 8698504

Pubmed Central ID

  • PMC174135

International Standard Serial Number (ISSN)

  • 0019-9567

Digital Object Identifier (DOI)

  • 10.1128/iai.64.7.2745-2751.1996


  • eng

Conference Location

  • United States