Antibody profiling in Colombian individuals before <i>P</i>. <i>vivax</i> challenge.

<p><i>Plasmodium vivax</i> protein arrays were probed with serum samples collected before challenge (day 0) and at four time-points afterwards, as shown in the schematic in <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0004563#pntd.0004563.g001" target="_blank">Fig 1</a>. <b>A</b>. Heat map showing serological profiles on day 0 prior to challenge for each Colombian naïve and semi-immune individual, and US controls for comparison. Raw signal intensities for each IVTT spot have been subtracted from the sample-specific median of background (IVTT control) spots, and the adjusted signal intensity represented by a color according to the key. Only the top 100 antigens are shown, ranked by average adjusted signals of both Colombian groups. <b>B</b>. Scatter plot of individual antigens, in which the average signal of each group (y-axis) is plotted against the average of all three groups (x-axis); the slope of the regression line is proportional to the overall breadth and intensity of the profile in each group. Each point represents the median fluorescence intensity (MFI) for all individuals examined in the particular group to a particular antigen. <b>C</b>. Bar chart of normalized array data (Log2 FOC) at 1:200 serum dilution. Only antigens with significant reactivity difference (p<0.05) between naïve and semi-immune volunteers are shown (raw p-values; green bars). Of all the significant antigens, nine were considered seropositive (i.e., using Log2 FOC >1 as the cutoff; red bracket); these are shown in <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0004563#pntd.0004563.t001" target="_blank">Table 1</a>.