Additional file 1: Table S1. of Evaluating antibody functional activity and strain-specificity of vaccine candidates for malaria in pregnancy using in vitro phagocytosis assays

The raw data supporting Fig. 1. (XLSX 37 kb

Longitudinal invasion inhibitory activity profiles of representative individuals.

<p>Individuals exhibited diverse invasion inhibitory activity against the 3D7 WT relative to the EBA knockout parasites overtime. Individual AD23 inhibited the EBA knockout parasites more than the parental parasite; individual AD50 inhibited the parental parasite more than the EBA knockout parasite lines.</p

Seasonal variation in overall differential inhibition of 3D7 WT and the knockout lines.

<p>There were no differences between the overall inhibition between the 3D7 WT and EBA knockout parasites through the seasons except for EBA175 knockout parasites in the months of July, October, and January. Values represent mean of all samples ± SEM.</p

Kaplan- Meier survival curves showing the proportion of individuals with antibody levels of >50% of the day 0 antibody level for all antigens among the different age groups and among individuals with different levels of exposure to <i>P</i>. <i>falciparum</i>.

<p>Kaplan- Meier survival curves showing the proportion of individuals with antibody levels of >50% of the day 0 antibody level for all antigens among the different age groups and among individuals with different levels of exposure to <i>P</i>. <i>falciparum</i>.</p

Relationship between invasion inhibitory antibodies to invasion pathway ligands parasitaemia and age.

<p>(A) Effects of antibodies directed against SA-dependent or SA-independent pathways on the mean parasitaemia. “<b>A</b>”, “<b>B</b>” represent individuals with only antibody responses to SA-dependent or SA-independent pathway invasion ligands, respectively. “<b>A and B”</b> represents individuals that presented a response to both pathways. (B) Effect of age on the acquisition of antibody responses to the two invasion pathways.</p

Comparison of EBA175 and PfRh2 antibody levels between individuals that switched between invasion inhibition patterns and those with unchanging invasion patterns.

<p>Bars represent the mean antibody levels and SEM. ‘‘Switchers” represents individuals that had fluctuating invasion inhibitory patterns while ‘‘Non-switchers” represents those that had stable invasion inhibitory pattern.</p

Pattern of differential inhibition of <i>P</i>. <i>falciparum</i> lines exhibited by individuals over time.

<p>The pie charts show the proportion of individuals that differentially inhibited 3D7WT invasion compared with 3D7 lines with genetically disrupted EBA genes (KO). The proportions of individuals with all observed outcomes are represented with various shades as shown. For example, “KO>WT only over time” means that the knock-out parasite was inhibited more than the wild-type and this was a stable pattern over time in the studied individuals.</p

Longitudinal antibody profile showing changes in antibody levels measured by ELISA and breadth of antibody responses in representative individuals over time.

<p>The scales of the y-axes on all the graphs are different due to the uniqueness of the titre values and parasitaemia of each individual. Individuals (2B and 2D) with ‘‘malaria” on some days had clinical symptoms of malaria on those occasions.</p

Prevalence and levels of antibodies to PfRh4 antigens.

<p> <b>Notes:</b></p>1<p>Seropositive (number of seropositive individuals) and percentage (%) of seropositive individuals were defined by IgG reactivity that was higher than the mean plus three standard deviations of control sera (unexposed donors) measured by ELISA. Median optical densities (OD) are displayed; [IQR] - interquartile range.</p>2<p>Age: ≤9.0 yrs indicates individuals younger than 9 years of age; >9.0 yrs indicates individuals older than 9 years of age.</p>3<p>Parasitemic status: PCR-, indicates <i>P. falciparum</i> was not detected by PCR; PCR+, indicates <i>P. falciparum</i> was detected by PCR.</p>4<p>P values were calculated using the chi-squared test or Fisher’s exact test for comparisons of seroprevalence, or using the Kruskal-Wallis test for comparisons of antibody level.</p

Expression of PfRh4 in clinical isolates from PNG.

<p>Notes: Results from immunofluorescence assays using blood smears of <i>P. falciparum</i> isolates from infected children. Isolates A–V were stained with DAPI and anti-PfRh4 antibody in order to investigate the rate of PfRh4 expression in clinical isolates. % Rh4 positive: proportion of DAPI-positive schizonts that were also PfRh4-positive. An arbitrary cut-off for positivity was set at 3 DAPI-positive schizonts that were also Rh4-positive. As a reference, schizonts of isolate 3D7 were stained with anti-PfRh4 antibody in 4 independent experiments to determine the average percentage of positive PfRh4 staining (mean 40.1%, range of 20.7%).</p