Size and composition of the B-cell compartment <i>ex vivo</i> influences B-cell expansion during culture.

<p>Flow cytometry analysis was performed to determine proportions and subsequently calculate absolute numbers of (A) total CD19+ B-cells (blue dots) and (B) IgG+CD19+ B-cells (orange dots) <i>ex vivo</i> and post-culture. <i>Ex vivo</i> proportions of (C) total CD19+ B-cells (blue dots) within viable PBMCs were plotted against the fold change in their absolute numbers, and (D) IgG+ B-cells (orange dots) within total CD19+ B-cells were plotted against the fold change in their proportion within the B-cell compartment. (E) Proportions of IgG+CD19+ B-cells (orange dots) and (F) IgG−CD19+ B-cells (green dots) within viable PBMCs were plotted against the fold increase in their respective absolute numbers post-culture compared to <i>ex vivo</i>. Colored dots show cultures from all 269 stimulated samples (3–7 time points per volunteer), while black dots show the cultures from only the 62 baseline samples (1 for each individual volunteer). The black dashed line indicates the median fold change (with value), grey dotted lines represent the upper and lower limit of the interquartile range. Spearman r and p values are shown for analysis of baseline samples (black dots) from the 62 donors assessed.</p

Antibodies used for <i>ex vivo</i> flow cytometry analysis.

a<p>Dump channel comprised of lineage markers to gate out non-relevant PBMC subsets.</p><p>n/a = not applicable.</p><p>BCR = B-cell receptor.</p

Antibodies used for post-culture flow cytometry analysis.

a<p>Dump channel comprised of lineage markers to gate out non-relevant PBMC subsets.</p><p>n/a = not applicable.</p><p>BCR = B-cell receptor.</p

Definition of B-cell subsets <i>ex vivo</i>.

<p>Definition of B-cell subsets <i>ex vivo</i>.</p

Example model predictions for blood parasite levels in a subset of individuals.

<p>Black bullets represent data points; black triangles are observations below the detection limit (dashed line). The solid black line represents the posterior mean. The shaded band around it represents the 2.5^th and 97.5^th percentiles of the predicted parasite concentrations, based on 8000 draws from the posterior distribution. Panel headers refer to unique identifiers for CHMI volunteers, which can also be found in the data (<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005255#pcbi.1005255.s008" target="_blank">S1 File</a>).</p

Simulated vaccine trial power to detect a statistically significant difference between an intervention and control group (T-test assuming unequal variances, setting <i>α</i> = 0.05).

<p>Simulations were performed for each combination of vaccine type (erythrocytic or hepatic), efficacy (50%, 60%, 70%, 80%, or 90% reduction in first-generation parasite loads or parasite multiplication rate), variation in efficacy between individuals (standard deviation or SD), and the frequency of blood samples taken: one per two days (8am or 4pm), or one (8am), two (8am, 4pm), or three (8am, 4pm, 10pm) per day. Power calculations for a wider range of vaccine efficacy (30%–95%) can be visualized with the graphical user interface in <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005255#pcbi.1005255.s009" target="_blank">S2 File</a>.</p

Study characteristics.

<p>Study characteristics.</p

Parameter estimates for parasite kinetics in mosquito-based, controlled human malaria infection.

<p>Parameter estimates for parasite kinetics in mosquito-based, controlled human malaria infection.</p

Matrix scatter plot of random effects for sources of inter-individual variation.

<p>Random effects (x-axes and y-axes) pertain to the average time of appearance of first generation blood parasites, the number of first cycle parasites, the multiplication rate of blood parasites, and the log-odds ratio of an individual having parasites detected during blood microscopy, adjusted for predicted parasite levels. Within each panel, each bullet represents the point estimate for one CHMI volunteer (<i>N</i> = 56), based on the mean of 8000 draws from the posterior.</p

Long-term RAS and CPS^a protection following <i>P. berghei</i> sporozoite challenge^b.

a<p>CPS mice received 24-days chloroquine treatment. Three of the six naïve mice challenged at t = 3months receive the same chloroquine treatment.</p>b<p>Mice were challenged by i.v. injection of 10.000 WT sporozoites. Protection was defined as negative blood-smears at day 21 after challenge.</p