Extended Data Fig. 10: Diminished anti-E. coli IgG and opsonization activity in newborn blood spots of babies with E. coli sepsis.

a–d, Anti-E. coli IgG levels in blood spots from babies with E. coli sepsis (n = 100) and matched controls (n = 296) titered against pooled neonatal clinical isolates (RS218, SCB12, SCB29, SCB61, SCB34, SCB58, SCB37, SCB60) (a), titered against pooled OmpA outer loop peptides (b), opsonization activity against eight pooled E. coli clinical isolates in THP1 macrophage (c) or HL60 neutrophil cells (d) (left), and probability of E. coli sepsis for each parameter using conditional logistic regression accounting for 1:3 case-control matching (anti-E. coli IgG, anti-OmpA IgG, and anti-E. coli opsonization THP1 cells), or standard logistic regression for anti-E. coli opsonization HL60 cells where separation between matched cases and controls was sufficient to prevent convergence of conditional logistic regression, with shading indicating 95% confidence intervals (right). Data are presented as mean values (bar) ± one standard deviation. e, Anti-E. coli IgG titres in blood spots from babies with E. coli sepsis (n = 100) compared with the average in matched control babies with infection (n = 100) titered against pooled eight neonatal clinical isolates evaluated by infection onset timing. f, IgG levels in blood spots of babies described in panel e (n = 100 [E. coli sepsis]; n = 100 [averaged control babies without infection]). g,h, IgG titers against in blood spots against pooled OmpA loop peptides (g) or scramble control peptides (h) for babies described in panel e (n = 100 [E. coli sepsis]; n = 100 [averaged control babies without infection]). i,j, Anti-E. coli opsonization activity in blood spot specimens against eight pooled E. coli clinical isolates in THP1 macrophage (i) or HL60 neutrophil cells (j) for babies described in panel e (n = 100 [E. coli sepsis]; n = 100 [averaged control babies without infection]). Each point represents the data from individual blood spot specimens of E. coli sepsis cases (red) or the average from 3 matched controls for each case (blue) with 95% confidence intervals highlighted. k, Anti-E. coli or anti-OmpA IgG titres, or anti-E. coli opsonization activity in THP1 macrophage or HL60 neutrophil cells of blood spots of babies identified with E. coli sepsis within the first 2 days after birth (n = 44) or later onset infection (n = 56). Differences between groups analysed using unparied (panel a-d) or paired Student’s t test (panel k), and between regression intercepts using Analysis of Covariance (e - j).

Source data