Extended Data Fig. 2: Overview of HI titres.
From: Immune imprinting in early life shapes cross-reactivity to influenza B virus haemagglutinin
(a) Correlations between antibody titres against the 19 IBV isolates from the main dataset (n = 322 serum samples). Virus isolates have been ordered by hierarchical clustering. (b) Antigenic characterization using human monoclonal antibodies against the IBV HA. End point titres from an HI assay are shown starting at 50 μg/ml. (c) Log2 HI titres against time (years) between sample collection and virus isolation (across all three datasets). (d) Log2 HI titres against time (years) between sample collection and virus isolation (across all three datasets) with individuals pooled into sample collection groups. For (C) and (D) the lines represent estimates using generalized additive models (GAMs) with 95% CI, accounting for repeated measurements on each individual by specifying a random effect. (e) Comparison of HI titres against cell and egg isolates in paired serums (n = 61) samples tested against cell or egg grown B/Phuket/2013 and B/Washington/2019. The number in blue indicated the difference in titres on the log2 scale. The boxplots show the median (centre line), quartiles (box limits) and maximum/minimum within 1.5x IQR above Q3 and below Q1(whiskers). P-values were generated from a Wilcoxon matched-pairs signed rank test (n = 61 samples from 2020). (f) Correlation between log2 HI titres against cell and egg grown B/Phuket/2013 and B/Washington/2019 viruses as described in C. (g) Correlation between log2 HI titres and microneutralization titres in 17 individuals tested against 10 viruses. In (F) and (G) the line represent estimates from linear regression with with 95% CI.
