Figure 2

Comparison between exposed and unexposed adults: monoplex and multiplex assays showing coated bead-stability over time. In the upper panel (a), the same serum from the exposed individual from Dielmo village (black bars) tested in figure 1 and serum from an unexposed adult (white bars) were compared at a dilution of 1:100 by the multiplex assay. The assay allows a clear separation of peptide-specific MFI between the two samples, whereas the backgrounds (MFI values with BSA-coated beads) were equivalent. The serum from the exposed individual from Dielmo village was also tested for the same Ab responses by the monoplex assay with single peptide-coated beads (gray bars). Results with monoplex and multiplex assays were almost identical (correlation coefficient R² = 0.9896). The lower panel (b) shows results obtained using peptide-coupled beads after 1 (white bars), 2 (light gray bars) and 3 (dark gray bars) months of storage at 4°C against the 1:100 diluted serum from the exposed adult from Dielmo village and the 1:100 diluted serum from the unexposed adult (black bars, superimposed to the corresponding time delay). MFIs were consistent for all Ags, except StarpR (the correlation coefficient comparing values using coated beads after 1 and 3 months for each peptide, except StarpR, was R² = 0.9874).