Fig. 7: Assessment of impact of egg adaptation on antigenicity.

a Analysis of post-vaccination serological responses to egg- and cell-grown virus pairs. Twenty human post-vaccination sera were tested by HI assay against the indicated virus. The Geometric Mean Titre (GMT) and 95% confidence interval was calculated for each virus assessed. b Amino acid mutations in the HA-1 sequence, as compared to the cell sequence is shown for each virus included in (a). *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. The difference in GMT was assessed using a multiple t-test.