Fig. 4.

Five-marker plasma signature assessed by up-converting phosphor lateral flow assays (UCP-LFA). Levels of αPGL-I IgM, IP-10, CRP, ApoA1 and S100A12 were measured by UCP-LFAs comparing 36 leprosy patients (LP, orange squares = multibacillary (MB) patients and blue dots = paucibacillary (PB) patients) to 20 endemic controls (EC = green dots). (a) Ratio values for the 5 markers tested were calculated by dividing the relative fluorescence units (RFU) from the test line (T) by the RFU from the flow controls (FC). The dotted line indicates the cut-off value for each markers as calculated by the Youden's index. Values above the cut-off line are considered a positive test result, the sum of all positive tests results in the values displayed for the five-marker signature. Cut-offs are shown in supplementary Table S5. (b) receiver operating characteristic curves (ROC) for MB and PB patients compared to EC showing all 5 markers tested (αPGL-I IgM (red), IP-10 (purple), CRP (green), ApoA1 (blue), S100A12 (grey)) and the five-marker signature (orange).