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- W1506126972 abstract "For the prevention of meningococcal infection caused by group B meningococci, the Netherlands Vaccine Institute (NVI) has developed a hexavalent Porin A (PorA) based Outer Membrane Vesicle (OMV) vaccine (Hexamen). In various clinical studies with HexaMen, differences in the immune responses to the individual PorAs were observed. Factors involved in the development of the PorA specific immune response were studied, including the role of B and T cells. Also, alternative formulations or immunization schedules using the available monovalent and hexavalent candidate vaccines were investigated to optimize the immune response. To address these issues, studies were undertaken using P1.7-2,4 as a model for a weakly immunogenic PorA antigen, while P1.5-1,2-2 was used as a strongly immunogenic PorA model antigen. The influence of the composition of a PorA OMV vaccine on the immune response was limited, indicating that these are caused by intrinsic properties of the PorA antigen itself. We investigated the possibility to optimize the immune response against weakly immunogenic PorAs using immunization schedules with both monovalent OMVs and HexaMen. Priming with two different weakly immunogenic PorAs followed by two doses of HexaMen, induced good responses against all serosubtypes. The early immune responses against a strong (P1.5-1,2-2) and a weak PorA immunogen (P1.7-,2 4) after monovalent immunization, revealed a delayed onset of high affinity IgG and SBA titers for the weak immunogen. A PorA-specific B cell ELISPOT showed that the lower IgG and SBA titers were not reflected by a lack of specific B cells or plasma cells, but were instead higher after the boost. Apparently, the P1.7-2,4 specific B cells have difficulties to generate high affinity antibodies and require more proliferation to obtain sufficient antibody production. This higher number of P1.7-2,4 specific memory B cell pool remained constant for over a year. We also found that memory B cells were induced already after one HexaMen immunization, and were reactive upon both immunization and intranasal exposure to live bacteria, indicating that this memory B cell pool may contribute to vaccine-induced protection in the absence of PorA specific bactericidal titers. Finally, we studied the involvement of CD4 T cells in the PorA specific response by the generation of a PorA (P1.5-1,2-2) specific T cell hybridoma. The recognized epitope was located in a transmembrane region with limited strain variation. Still, one amino acid variation either inside or outside the CD4 T cell epitope could greatly reduce the efficiency of PorA specific CD4 T cell activation. In conclusion, a multivalent PorA OMV vaccine is to date the best vaccine to protect against meningococcal disease in an endemic situation. Differences in PorA specific immune responses are caused by intrinsic properties of PorA and the interaction with the complete immune system. Furthermore, our studies showed that the PorA specific immune responses may be enhanced by optimizing the vaccination schedule." @default.
- W1506126972 created "2016-06-24" @default.
- W1506126972 creator A5036042187 @default.
- W1506126972 date "2006-06-08" @default.
- W1506126972 modified "2023-09-27" @default.
- W1506126972 title "Immunogenicity of meningococcal PorA antigens in OMV vaccines" @default.
- W1506126972 cites W1499589601 @default.
- W1506126972 cites W1510773753 @default.
- W1506126972 cites W1522434856 @default.
- W1506126972 cites W1531148794 @default.
- W1506126972 cites W1538652950 @default.
- W1506126972 cites W1566165411 @default.
- W1506126972 cites W1567037104 @default.
- W1506126972 cites W1572881837 @default.
- W1506126972 cites W1576152613 @default.
- W1506126972 cites W1576377498 @default.
- W1506126972 cites W1589591129 @default.
- W1506126972 cites W1590830087 @default.
- W1506126972 cites W1622088669 @default.
- W1506126972 cites W1734385177 @default.
- W1506126972 cites W1851989560 @default.
- W1506126972 cites W1911780585 @default.
- W1506126972 cites W1934670278 @default.
- W1506126972 cites W1935940544 @default.
- W1506126972 cites W1945802002 @default.
- W1506126972 cites W1966756198 @default.
- W1506126972 cites W1967828810 @default.
- W1506126972 cites W1969184830 @default.
- W1506126972 cites W1969623216 @default.
- W1506126972 cites W1971350415 @default.
- W1506126972 cites W1971569916 @default.
- W1506126972 cites W1974423506 @default.
- W1506126972 cites W1975355256 @default.
- W1506126972 cites W1976230577 @default.
- W1506126972 cites W1976422965 @default.
- W1506126972 cites W1976546346 @default.
- W1506126972 cites W1979986360 @default.
- W1506126972 cites W1981797020 @default.
- W1506126972 cites W1982573460 @default.
- W1506126972 cites W1987016144 @default.
- W1506126972 cites W1988247082 @default.
- W1506126972 cites W1991844560 @default.
- W1506126972 cites W1993198059 @default.
- W1506126972 cites W1995379601 @default.
- W1506126972 cites W1996141674 @default.
- W1506126972 cites W1996256410 @default.
- W1506126972 cites W1998179482 @default.
- W1506126972 cites W1998558781 @default.
- W1506126972 cites W2003709444 @default.
- W1506126972 cites W2004908118 @default.
- W1506126972 cites W2007950400 @default.
- W1506126972 cites W2012163630 @default.
- W1506126972 cites W2012433731 @default.
- W1506126972 cites W2012619809 @default.
- W1506126972 cites W2017835421 @default.
- W1506126972 cites W2020870088 @default.
- W1506126972 cites W2025309434 @default.
- W1506126972 cites W2028960154 @default.
- W1506126972 cites W2031812411 @default.
- W1506126972 cites W2034293576 @default.
- W1506126972 cites W2037308991 @default.
- W1506126972 cites W2038042144 @default.
- W1506126972 cites W2038494844 @default.
- W1506126972 cites W2039033277 @default.
- W1506126972 cites W2041659749 @default.
- W1506126972 cites W2042369282 @default.
- W1506126972 cites W2044099387 @default.
- W1506126972 cites W2044342990 @default.
- W1506126972 cites W2044418935 @default.
- W1506126972 cites W2045221557 @default.
- W1506126972 cites W2046267384 @default.
- W1506126972 cites W2049294116 @default.
- W1506126972 cites W2057692835 @default.
- W1506126972 cites W2057809738 @default.
- W1506126972 cites W2058541383 @default.
- W1506126972 cites W2059783102 @default.
- W1506126972 cites W2059865176 @default.
- W1506126972 cites W2060694962 @default.
- W1506126972 cites W2060696129 @default.
- W1506126972 cites W2064474732 @default.
- W1506126972 cites W2067488232 @default.
- W1506126972 cites W2069285405 @default.
- W1506126972 cites W2069469281 @default.
- W1506126972 cites W2070553347 @default.
- W1506126972 cites W2073533707 @default.
- W1506126972 cites W2073678729 @default.
- W1506126972 cites W2074792304 @default.
- W1506126972 cites W2078598660 @default.
- W1506126972 cites W2078791944 @default.
- W1506126972 cites W2080332703 @default.
- W1506126972 cites W2080885816 @default.
- W1506126972 cites W2080957576 @default.
- W1506126972 cites W2086071384 @default.
- W1506126972 cites W2086566503 @default.
- W1506126972 cites W2086909360 @default.
- W1506126972 cites W2089800576 @default.
- W1506126972 cites W2091046293 @default.
- W1506126972 cites W2091085026 @default.
- W1506126972 cites W2093512259 @default.
- W1506126972 cites W2094682437 @default.