Unknown

Dataset Information

0

Cell mediated immune responses following revaccination with an influenza A/H5N1 vaccine.


ABSTRACT: PURPOSE:The study aims were to determine whether inactivated influenza A/H5N1 vaccine administration elicited cell mediated immune (CMI) responses and the impact of adjuvant, vaccine dose and subject age on these responses. METHODS:Adults who were previously primed with either adjuvanted or unadjuvanted, inactivated, A/H5N1/Vietnam/1203/2004 (Clade 1) vaccine or unprimed (received placebo) in previous vaccine studies were randomized to receive one (primed) or two (unprimed) 15- or 90-mcg doses of inactivated, A/H5N1/Indonesia/05/05 (Clade 2) vaccine. Peripheral blood mononuclear cells (PBMCs) were collected and analyzed from a subset of vaccinees to assess CMI responses using IFN-? and granzyme B ELISPOT assays. Cytokine measurements were performed on PBMC supernatants after stimulation with H5N1 virus. RESULTS:PBMCs were available from 177 participants; 88 and 89 received 15-mcg and 90-mcg of unadjuvanted clade 2 vaccine, respectively. Following H5N1 clade 1 stimulation, IFN-? but not granzyme B normalized spot-forming cell numbers had statistically significant increased numbers at each of the post-vaccination timepoints compared to baseline in pooled analyses of all vaccine doses and age groups. Clade 2 stimulation resulted in statistically significant increased numbers of IFN-? cells only 180 days following the last vaccination. Responses were similar among younger and older study participants, as were responses among those primed with alum-adjuvanted or non-adjuvanted clade 1 H5N1 vaccines. The dosage of clade 2 vaccine did not impact CMI responses among primed subjects, but responses were statistically significantly greater in unprimed recipients of the 90-mcg dosage compared to unprimed recipients of the 15-mcg dosage. IFN-? levels in the supernatants of stimulated PBMC were strongly correlated with IFN-? ELISPOT results. CONCLUSION:CMI responses occur in adults administered influenza A/H5N1 inactivated influenza vaccine.

SUBMITTER: Mbawuike IN 

PROVIDER: S-EPMC4713282 | BioStudies | 2016-01-01

REPOSITORIES: biostudies

Similar Datasets

2009-01-01 | S-EPMC2674105 | BioStudies
2014-01-01 | S-EPMC3995799 | BioStudies
2019-01-01 | S-EPMC6773406 | BioStudies
2014-01-01 | S-EPMC4008266 | BioStudies
2015-01-01 | S-EPMC4309450 | BioStudies
2018-01-01 | S-EPMC5780465 | BioStudies
2016-01-01 | S-EPMC5240149 | BioStudies
2013-01-01 | S-EPMC5780732 | BioStudies
2019-01-01 | S-EPMC6519114 | BioStudies
2010-01-01 | S-EPMC3004909 | BioStudies