tetano
Editor, Senior Moderator
J Infect Dis. 2014 Nov 6. pii: jiu616. [Epub ahead of print]
The effect of influenza A(H5N1) pre-pandemic priming on CD4 T-cell responses.
Nayak JL1, Richards KA2, Yang H3, Treanor JJ4, Sant AJ2.
Author information
Abstract
INTRODUCTION:
Previous priming with avian influenza vaccines results in more rapid and robust neutralizing antibody responses upon revaccination, but the role CD4 T cells play in this process is not currently known.
METHODS:
Human subjects previously enrolled in trials of inactivated H5N1 vaccines and na?ve subjects were immunized with an inactivated subunit A/Indonesia/5/05 H5N1 vaccine. Neutralizing antibody responses were measured by microneutralization assay and hemagluttinin and nucleoprotein specific CD4 T-cell responses were quantified using IFNγ Elispot assays.
RESULTS:
While vaccination induced barely detectable CD4 T-cell responses specific for HA in the previously unprimed group, primed subjects had readily detectable HA-specific memory CD4 T cells at baseline and mounted a more robust response to HA-specific epitopes post-vaccination. There were no differences between groups when conserved NP-specific CD4 T-cell responses were examined. Interestingly, neutralizing antibody responses following revaccination were significantly higher in individuals that mounted a CD4 T-cell response to the H5 HA protein, a correlation not observed for NP-specific responses.
CONCLUSIONS:
These findings suggest that pre-pandemic vaccination results in an enriched population of HA-specific CD4 T cells that are recruited on rechallenge with a drifted vaccine variant and contribute to more robust and rapid neutralizing antibody responses.
? The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
PMID:
25378637
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25378637
The effect of influenza A(H5N1) pre-pandemic priming on CD4 T-cell responses.
Nayak JL1, Richards KA2, Yang H3, Treanor JJ4, Sant AJ2.
Author information
Abstract
INTRODUCTION:
Previous priming with avian influenza vaccines results in more rapid and robust neutralizing antibody responses upon revaccination, but the role CD4 T cells play in this process is not currently known.
METHODS:
Human subjects previously enrolled in trials of inactivated H5N1 vaccines and na?ve subjects were immunized with an inactivated subunit A/Indonesia/5/05 H5N1 vaccine. Neutralizing antibody responses were measured by microneutralization assay and hemagluttinin and nucleoprotein specific CD4 T-cell responses were quantified using IFNγ Elispot assays.
RESULTS:
While vaccination induced barely detectable CD4 T-cell responses specific for HA in the previously unprimed group, primed subjects had readily detectable HA-specific memory CD4 T cells at baseline and mounted a more robust response to HA-specific epitopes post-vaccination. There were no differences between groups when conserved NP-specific CD4 T-cell responses were examined. Interestingly, neutralizing antibody responses following revaccination were significantly higher in individuals that mounted a CD4 T-cell response to the H5 HA protein, a correlation not observed for NP-specific responses.
CONCLUSIONS:
These findings suggest that pre-pandemic vaccination results in an enriched population of HA-specific CD4 T cells that are recruited on rechallenge with a drifted vaccine variant and contribute to more robust and rapid neutralizing antibody responses.
? The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
PMID:
25378637
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25378637