Janice Z Jia, Carolyn A Cohen, Haogao Gu, Milla R McLean, Raghavan Varadarajan, Nisha Bhandari, Malik Peiris, Gabriel M Leung, Leo L M Poon, Tim Tsang, Amy W Chung, Benjamin J Cowling, Nancy H L Leung, Sophie A Valkenburg
Cross-reactive antibodies with Fc receptor (FcR) effector functions may mitigate pandemic virus impact in the absence of neutralizing antibodies. In this exploratory study, we use serum from a randomized placebo-controlled trial of seasonal trivalent influenza vaccination in children (NCT00792051) conducted at the onset of the 2009 H1N1 pandemic (pH1N1) and monitored for infection. We found that seasonal vaccination increases pH1N1 specific antibodies and FcR effector functions. Furthermore, prospective baseline antibody profiles after seasonal vaccination, prior to pH1N1 infection, show that unvaccinated uninfected children have elevated ADCC effector function, FcγR3a and FcγR2a binding antibodies to multiple pH1N1 proteins, past seasonal and avian (H5, H7 and H9) strains...
April 13, 2024: Nature Communications