Quantifying the Importance of MSP1-19 as a Target of Growth-Inhibitory and Protective Antibodies against Plasmodium falciparum in Humans
Figure 3
Reproducibility of PfMSP1-19 specific growth inhibition assays and levels of PfMSP1-19 specific inhibition for representative samples.
(A) Correlation of PfMSP1-19 line growth between duplicate experiments for 85 samples of the non-dialysed Mugil plasma samples showing a high level of assay reproducibility (rs = 0.88, n = 85, P<0.0001). (B) Subset of non-dialysed Mugil plasma samples showing total growth inhibitory activity but little or no PfMSP1-19 specific inhibitory activity in 2 cycle assays. Confirmation that the assay was able to measure PfMSP1-19 specific inhibition was provided through the use of inhibitory rabbit antisera raised against PfMSP1-19 (anti-Pf). (C) Correlation of PfMSP1-19 line growth between duplicate experiments for dialysed Mugil plasma samples showing a high level of assay reproducibility (rs = 0.93, n = 204, P<0.0001). (D) Subset of dialysed Mugil plasma showing total growth inhibitory activity but little or no PfMSP1-19 specific inhibitory activity in 2 cycle assays. Correlation between parasite growth measured in flow cytometry or microscopy based 1 cycle assays for (E) the PcMSP1-19 line (rs = 0.72, n = 25, P<0.0001) and (F) the PfMSP1-19 line (rs = 0.59, n = 25, P = 0.0018) highlight comparable levels of growth between the two methods. Parasite growth was expressed as a percentage of the mean growth of a panel of non-dialysed or dialysed Melbourne control sera included on each assay plate.