Clinical and Vaccine Immunology - CVI
Geisel School of Medicine
The 2009 pandemic H1N1 (pH1N1) influenza virus carried a swine-origin hemagglutinin (HA) that was closely related to the HAs of pre-1947 H1N1 viruses but highly divergent from the HAs of recently circulating H1N1 strains. Consequently, prior ex- posure to pH1N1-like viruses was mostly limited to individuals over the age of about 60 years. We related age and associated dif- ferences in immune history to the B cell response to an inactivated monovalent pH1N1 vaccine given intramuscularly to subjects in three age cohorts: 18 to 32 years, 60 to 69 years, and >70 years. The day 0 pH1N1-specific hemagglutination inhibition (HAI) and microneutralization (MN) titers were generally higher in the older cohorts, consistent with greater prevaccination exposure to pH1N1-like viruses. Most subjects in each cohort responded well to vaccination, with early formation of circulating virus- specific antibody (Ab)-secreting cells and >4-fold increases in HAI and MN titers. However, the response was strongest in the 18- to 32-year cohort. Circulating levels of HA stalk-reactive Abs were increased after vaccination, especially in the 18- to 32-year cohort, raising the possibility of elevated levels of cross-reactive neutralizing Abs. In the young cohort, an increase in MN activ- ity against the seasonal influenza virus A/Brisbane/59/07 after vaccination was generally associated with an increase in the anti- Brisbane/59/07 HAI titer, suggesting an effect mediated primarily by HA head-reactive rather than stalk-reactive Abs. Our find- ings support recent proposals that immunization with a relatively novel HA favors the induction of Abs against conserved epitopes. They also emphasize the need to clarify how the level of circulating stalk-reactive Abs relates to resistance to influenza.
Sangster MY, Baer J, Santiago FW, Fitzgerald T, Ilyushina NA, Sundararajan A, Henn AD, Krammer F, Yang H, Luke CJ, Zand MS, Wright PF, Treanor JJ, Topham DJ, Subbarao K. B cell response and hemagglutinin stalk-reactive antibody production in different age cohorts following 2009 H1N1 influenza virus vaccination. Clin Vaccine Immunol. 2013 Jun;20(6):867-76. doi: 10.1128/CVI.00735-12. Epub 2013 Apr 10. PMID: 23576673; PMCID: PMC3675965.
Dartmouth Digital Commons Citation
Sangster, Mark Y.; Baer, Jane; Santiago, Felix W.; Fitzgerald, Theresa T.; and Ilyushina, Natalia A., "B Cell Response and Hemagglutinin Stalk-Reactive Antibody Production in Different Age Cohorts following 2009 H1N1 Influenza Virus Vaccination" (2013). Dartmouth Scholarship. 714.