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Figure 1

From: Naturally acquired antibodies against Plasmodium vivax pre-erythrocytic stage vaccine antigens inhibit sporozoite invasion of human hepatocytes in vitro

Figure 1

Profile of naturally acquired IgG antibodies against PE antigens. (a) Antigen-specific antibody levels in plasma samples from Thai P. vivax infected patients (n = 51) were measured by indirect ELISA against recombinant CSP, SSP3, SPECT1, and CelTOS. Data is expressed as reactive index (RI) units, calculated by dividing the mean OD value of each patient sample by a cut-off value. The cut-off value was calculated as the mean OD + 2 SD of 6 naïve North American control samples75. Each point on the graph represents individual RI units with median and interquartile range. Plasma samples with RI < 1 (dotted lines) are considered not reactive (b) Frequency of IgG antibodies against respective antigens classified into HR (RI ≥ mean reactivity of all samples), LR (RI < mean reactivity of all samples but > cut-off value), and NR (RI < cut-off value). (c) Number of individuals with cross-reactive IgG antibodies to the different antigens.

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