Fig 1. Changes in frequency (cells/ml) of B cells induced by wt S. Typhi infection.
Panel A displays the gating strategy used to identify various B cell subsets. Whole B cells were identified using CD19. Plasmablasts (PB) were identified as B cells (CD19+) expressing high levels of CD27 and CD38. Non-PB cells were classified into various memory B (BM) subsets using the IgD/CD27 classification: (i) Sm CD27+ (CD27+IgD-), (ii) Sm CD27- (CD27-IgD-), (iii) Um (CD27+IgD+) and (iv) Naïve (CD27-IgD+). The frequency (cells/ml) of whole B cells, PB and BM subsets in TD (blue symbols) and NoTD (brown symbols) volunteers before wild-type challenge is shown in B, C and D, respectively. Shown in panel E are the time courses of the frequency of B cells after challenge in TD (solid blue circles) and NoTD (solid brown squares) volunteers. The time frame AroundTD is indicated by the blue rectangle with dotted lines. AroundTD in TD volunteers include the day in which typhoid was diagnosed (TD+0h) and two extra time points, 48h and 96h post-diagnosis (TD+48h and TD+96h, respectively), in which blood samples were collected. Shown in F are the data of B cells from TD (solid blue circles) and NoTD (solid brown squares) volunteers in the AroundTD time frame. Shown in G are the data of B cells from TD (open blue circles) and NoTD (open brown squares) in the AfterTD time frame (days 14, 21 and 28 for TD and NoTD volunteers). Time course, AroundTD and AfterTD data of the frequency of plasmablasts (PB) is shown in H, I and J, respectively. Shown is the P value from the mixed effects model analysis. Significant differences are highlighted in light green. Mean ± SD are presented in all graphs.