tetano
Editor, Senior Moderator
J Infect Dis. 2012 Sep 11. [Epub ahead of print]
A(H1N1)pdm09 vaccination of healthcare workers: Improved immune responses in low responders following revaccination.
Pathirana RD, Bredholt G, Akselsen PE, Pedersen GK, Cox RJ.
Source
Influenza Centre, The Gade Institute, University of Bergen, Bergen, Norway.
Abstract
Background. We conducted a clinical trial in October 2009 to evaluate the immunogenicity of the AS03-adjuvanted influenza vaccine (pH1N1-vaccine) in healthcare workers (HCW) (www.clinicaltrials.gov, NCT01003288). By 2 weeks post-vaccination, 97% had protective hemagglutinin inhibition (HI) titers (≥ 40) however, 16% were low responders (LR) and failed to maintain a protective response 90 days post-vaccination.Methods. We analyzed the humoral responses (HI, antibody-secreting-cell (ASC) and serum immunoglobulin G (IgG)) of 15 LR and compared to 25 control HCW. Twelve LR were revaccinated with the pH1N1-vaccine and 7 were subsequently vaccinated with the 2010 seasonal trivalent influenza vaccine (TIV) and we conducted a long-term analysis of the humoral and CD4(+) T-helper (Th) 1 responses.Results. The LR had a slower HI antibody response than the controls, with protective antibody titers not reached until two weeks post-vaccination in the majority of the subjects. The LR also had significantly lower IgG ASCs at day 7 and HA1-specific serum IgG responses at day 21 compared with the control subjects. Revaccination with the pH1N1-vaccine elicited rapid HI antibody, ASC, memory B cell and multifunctional CD4(+) Th1 cell responses.Conclusion. This study shows that revaccination of low-responding HCW with the pH1N1-vaccine is required for maintaining long-term protection.
PMID:
22969149
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22969149
A(H1N1)pdm09 vaccination of healthcare workers: Improved immune responses in low responders following revaccination.
Pathirana RD, Bredholt G, Akselsen PE, Pedersen GK, Cox RJ.
Source
Influenza Centre, The Gade Institute, University of Bergen, Bergen, Norway.
Abstract
Background. We conducted a clinical trial in October 2009 to evaluate the immunogenicity of the AS03-adjuvanted influenza vaccine (pH1N1-vaccine) in healthcare workers (HCW) (www.clinicaltrials.gov, NCT01003288). By 2 weeks post-vaccination, 97% had protective hemagglutinin inhibition (HI) titers (≥ 40) however, 16% were low responders (LR) and failed to maintain a protective response 90 days post-vaccination.Methods. We analyzed the humoral responses (HI, antibody-secreting-cell (ASC) and serum immunoglobulin G (IgG)) of 15 LR and compared to 25 control HCW. Twelve LR were revaccinated with the pH1N1-vaccine and 7 were subsequently vaccinated with the 2010 seasonal trivalent influenza vaccine (TIV) and we conducted a long-term analysis of the humoral and CD4(+) T-helper (Th) 1 responses.Results. The LR had a slower HI antibody response than the controls, with protective antibody titers not reached until two weeks post-vaccination in the majority of the subjects. The LR also had significantly lower IgG ASCs at day 7 and HA1-specific serum IgG responses at day 21 compared with the control subjects. Revaccination with the pH1N1-vaccine elicited rapid HI antibody, ASC, memory B cell and multifunctional CD4(+) Th1 cell responses.Conclusion. This study shows that revaccination of low-responding HCW with the pH1N1-vaccine is required for maintaining long-term protection.
PMID:
22969149
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22969149