tetano
Editor, Senior Moderator
Influenza Other Respi Viruses. 2013 Jul 25. doi: 10.1111/irv.12140. [Epub ahead of print]
Effect of passive immunization on immunogenicity and protective efficacy of vaccination against a Mexican low-pathogenic avian H5N2 influenza virus.
Forrest HL, Garcia A, Danner A, Seiler JP, Friedman K, Webster RG, Jones JC.
Source
Division of Virology, Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN, USA.
Abstract
BACKGROUND:
Despite the use of vaccines, low-pathogenic (LP) H5N2 influenza viruses have continued to circulate and evolve in chickens in Mexico since 1993, giving rise to multiple genetic variants. Antigenic drift is partially responsible for the failure to control H5N2 influenza by vaccination; the contribution of maternal antibodies to this problem has received less attention.
METHODS:
We investigated the effect of different antisera on the efficacy of vaccination and whether booster doses of vaccine can impact immune suppression.
RESULTS:
While single doses of inactivated oil emulsion vaccine to currently circulating H5N2 influenza viruses provide partial protection from homologous challenge, chickens that receive high-titer homologous antisera intraperitoneally before vaccination showed effects ranging from added protection to immunosuppression. Post-infection antisera were less immunosuppressive than antisera obtained from field-vaccinated chickens. Homologous, post-infection chicken antisera provided initial protection from virus challenge, but reduced the induction of detectable antibody responses. Homologous antisera from field-vaccinated chickens were markedly immunosuppressive, annulling the efficacy of the vaccine and leaving the chickens as susceptible to infection as non-vaccinated birds. Booster doses of vaccine reduced the immunosuppressive effects of the administered sera.
CONCLUSION:
Vaccine efficacy against LP H5N2 in Mexico can be severely reduced by maternal antibodies. Source-dependent antisera effects offer the possibility of further elucidation of the immunosuppressive components involved.
? 2013 John Wiley & Sons Ltd.
KEYWORDS:
H5N2, Mexico, avian influenza, immunosuppression, maternal immunity, vaccine
PMID:
23889740
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23889740
Effect of passive immunization on immunogenicity and protective efficacy of vaccination against a Mexican low-pathogenic avian H5N2 influenza virus.
Forrest HL, Garcia A, Danner A, Seiler JP, Friedman K, Webster RG, Jones JC.
Source
Division of Virology, Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN, USA.
Abstract
BACKGROUND:
Despite the use of vaccines, low-pathogenic (LP) H5N2 influenza viruses have continued to circulate and evolve in chickens in Mexico since 1993, giving rise to multiple genetic variants. Antigenic drift is partially responsible for the failure to control H5N2 influenza by vaccination; the contribution of maternal antibodies to this problem has received less attention.
METHODS:
We investigated the effect of different antisera on the efficacy of vaccination and whether booster doses of vaccine can impact immune suppression.
RESULTS:
While single doses of inactivated oil emulsion vaccine to currently circulating H5N2 influenza viruses provide partial protection from homologous challenge, chickens that receive high-titer homologous antisera intraperitoneally before vaccination showed effects ranging from added protection to immunosuppression. Post-infection antisera were less immunosuppressive than antisera obtained from field-vaccinated chickens. Homologous, post-infection chicken antisera provided initial protection from virus challenge, but reduced the induction of detectable antibody responses. Homologous antisera from field-vaccinated chickens were markedly immunosuppressive, annulling the efficacy of the vaccine and leaving the chickens as susceptible to infection as non-vaccinated birds. Booster doses of vaccine reduced the immunosuppressive effects of the administered sera.
CONCLUSION:
Vaccine efficacy against LP H5N2 in Mexico can be severely reduced by maternal antibodies. Source-dependent antisera effects offer the possibility of further elucidation of the immunosuppressive components involved.
? 2013 John Wiley & Sons Ltd.
KEYWORDS:
H5N2, Mexico, avian influenza, immunosuppression, maternal immunity, vaccine
PMID:
23889740
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23889740