In subjects who had previously received antigenically matched influenza A ( H@N@ ) pLAIV followed by @ dose of ISIV compared with those who were naive to influenza A ( H@N@ ) and LAIV and received @ doses of ISIV , we observed an increased frequency of antibody response ( @ % vs @ % , by the hemagglutination inhibition assay ) and a significantly higher antibody titer ( @ vs @ ; P = @ ) .