tetano
Editor, Senior Moderator
Vaccine. 2012 Jun 29. [Epub ahead of print]
A cell culture-derived whole-virus H5N1 vaccine induces long-lasting cross-clade protective immunity in mice which is augmented by a homologous or heterologous booster vaccination.
Sabarth N, Savidis-Dacho H, Schwendinger MG, Br?hl P, Portsmouth D, Crowe BA, Kistner O, Barrett PN, Kreil TR, Howard MK.
Source
Vaccine R&D, Baxter BioScience, Biomedical Research Centre, Uferstra?e 15, A-2304 Orth/Donau, Austria.
Abstract
BACKGROUND:
Preparation for an H5N1 influenza pandemic in humans could include priming the population in the pre-pandemic period with a vaccine produced from an existing H5N1 vaccine strain, with the possibility of boosting with a pandemic virus vaccine when it becomes available. We investigated the longevity of the immune response after one or two priming immunizations with a whole-virus H5N1 vaccine and the extent to which this can be boosted by later immunization with either a homologous or heterologous vaccine.
METHODS:
Mice received one or two priming immunizations with a Vero cell culture-derived, whole-virus clade 1 H5N1 vaccine formulated to contain either 750ng or 30ng hemagglutinin. Six months after the first priming immunization, mice received either a booster immunization with the same clade 1 vaccine or a heterologous clade 2.1 vaccine, or buffer. Humoral and cellular immune responses were evaluated before and at regular intervals after immunizations. Three weeks after booster immunization, mice were challenged with a lethal dose of wild-type H5N1 virus from clades 1, 2.1 or 2.2 and survival was monitored for 14 days.
RESULTS:
One or two priming immunizations with the 750ng or 30ng HA formulations, respectively, induced H5N1-neutralizing antibody titers which were maintained for ≥6 months and provided long-term cross-clade protection against wild-type virus challenge. Both humoral and cellular immune responses were substantially increased by a booster immunization after 6 months. The broadest protective immunity was provided by an immunization regimen consisting of one or two priming immunizations with a clade 1 vaccine and a boosting immunization with a clade 2.1 vaccine.
CONCLUSIONS:
These data support the concept that pre-pandemic vaccination can provide robust and long-lasting H5N1 immunity which could be effectively boosted either with another pre-pandemic vaccine or with the pandemic strain vaccine.
Copyright ? 2012. Published by Elsevier Ltd.
PMID:
22749797
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22749797
A cell culture-derived whole-virus H5N1 vaccine induces long-lasting cross-clade protective immunity in mice which is augmented by a homologous or heterologous booster vaccination.
Sabarth N, Savidis-Dacho H, Schwendinger MG, Br?hl P, Portsmouth D, Crowe BA, Kistner O, Barrett PN, Kreil TR, Howard MK.
Source
Vaccine R&D, Baxter BioScience, Biomedical Research Centre, Uferstra?e 15, A-2304 Orth/Donau, Austria.
Abstract
BACKGROUND:
Preparation for an H5N1 influenza pandemic in humans could include priming the population in the pre-pandemic period with a vaccine produced from an existing H5N1 vaccine strain, with the possibility of boosting with a pandemic virus vaccine when it becomes available. We investigated the longevity of the immune response after one or two priming immunizations with a whole-virus H5N1 vaccine and the extent to which this can be boosted by later immunization with either a homologous or heterologous vaccine.
METHODS:
Mice received one or two priming immunizations with a Vero cell culture-derived, whole-virus clade 1 H5N1 vaccine formulated to contain either 750ng or 30ng hemagglutinin. Six months after the first priming immunization, mice received either a booster immunization with the same clade 1 vaccine or a heterologous clade 2.1 vaccine, or buffer. Humoral and cellular immune responses were evaluated before and at regular intervals after immunizations. Three weeks after booster immunization, mice were challenged with a lethal dose of wild-type H5N1 virus from clades 1, 2.1 or 2.2 and survival was monitored for 14 days.
RESULTS:
One or two priming immunizations with the 750ng or 30ng HA formulations, respectively, induced H5N1-neutralizing antibody titers which were maintained for ≥6 months and provided long-term cross-clade protection against wild-type virus challenge. Both humoral and cellular immune responses were substantially increased by a booster immunization after 6 months. The broadest protective immunity was provided by an immunization regimen consisting of one or two priming immunizations with a clade 1 vaccine and a boosting immunization with a clade 2.1 vaccine.
CONCLUSIONS:
These data support the concept that pre-pandemic vaccination can provide robust and long-lasting H5N1 immunity which could be effectively boosted either with another pre-pandemic vaccine or with the pandemic strain vaccine.
Copyright ? 2012. Published by Elsevier Ltd.
PMID:
22749797
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22749797