Skip to main content
[Preprint]. 2024 Jul 19:rs.3.rs-4633976. [Version 1] doi: 10.21203/rs.3.rs-4633976/v1

Figure 2. The rPagSP02+rPagSP06 composite biomarker of exposure to Ph. argentipes exhibits high sensitivity and specificity in Sri Lanka.

Figure 2

(a) Anti-salivary IgG antibodies against 2 μg/mL of salivary gland homogenate (SGH) from Sri Lankan Ph. argentipes, cut-off at 0.072. (b) Anti-salivary IgG antibodies against 1 μg/mL of rPagSP02+rPagSP06 composite recombinant salivary antigen of Ph. argentipes, cut-off at 0.082. The cut-off value of the indirect ELISA was calculated using a receiver operating characteristic (ROC) curve with OD values of non-endemic (NE) individuals (negative controls, n=15) and sera from clinically confirmed CL-positive patients (Positive controls, n=30). Antigens were tested against serum samples (1:50 dilution) from 546 individuals living in endemic areas of CL, 30 newly diagnosed CL patients and 15 non-endemic individuals. (c,d) Receiver operating characteristic (ROC) curve for indirect ELISA of SGH, area under the curve (AUC) value equals to 0.979 (c) and rPagSP02+rPagSP06, AUC value equals to 1.000 (d). (e) Pearson’s rank correlation test between Ph. argentipes SGH and rPagSP02+rPagSP06. Correlation coefficient r= 0.869 at 95% CI. A two-tailed p < 0.05 as considered statistically significant.