Multiplex immunoassay antigen screening with serum from benznidazole treated and non-treated <i>T</i>. <i>cruzi</i> infected mice.

(A) Images of multiplex assays screened with serum from a vehicle treated infected BALB/c mouse (BN201-4). (B) Images after screening with serum from an infected mouse (BN206-4) that had been subjected to benznidazole treatment (100 mg kg-1, 5 days), initiated 101 days post-infection (dpi). The dpi are indicated. Antigens were arrayed in duplicate as in Fig 1. For illustrative purposes, specific antigens are framed as follows: IBAG39 (green), IBAG257 (blue), IBAG108 (red), IBAG37 (black), IBAG38 (yellow), IBAG101 (orange), IBAG131 (purple). (C) Longitudinal data showing the proportion of serum samples reacting with selected antigens at a net intensity >10 (minimum set threshold) at each time point (n = 45). Each IBAG is indicated by an arrow. The curves of the two most reactive antigens IBAG257(blue) and IBAG39 (green) overlap.</p

Summary of the linear mixed model (LMM) regression output for each biomarker and in each subgroup.

Both the intercept and slope of the linear regression of each antigen corresponds to an average over the 15 mice in each group. Intercept > 10. Blue: significant p-values (Red: high intensity. We have data on several mice where we have treatment group and biomarker reactivity measured at different time points. Where all mice have the same slope and intercept relating reactivity to time and treatment group, a regular multiple linear regression model can be fitted with time and treatment group as the predictor, and reactivity as the response. Biomarker reactivities < 10 were considered below the positive reactivity threshold and were regarded as non-reactive. Slopes compared between treatment groups were assigned as different based on a 5% significance level.</p

Bioluminescence total flux and IBAG39 intensity of reactivity for each of the 15 mice treated with 100 mg kg^-1 benznidazole (BZ).

The linear correlation coefficient R is given in each graph. The red curve is intensity of IBAG39 and the black curve is log (total flux (p/s)).</p

<i>Ex vivo</i> imaging of benznidazole-treated mice at the experimental end-point.

At 301 days post infection, mice that had been treated with 100 mg kg-1 benznidazole for 5 days (S1 Fig) were euthanized and subjected to ex vivo imaging (Methods). Bioluminescent foci (examples highlighted by white arrows) were detected in 4 mice, which were designated as non-cured. The organs and tissues are organized as shown in Fig 4. (PPTX)</p

Average change of IBAG reactivity over time, based on the linear prediction model for mice treated with vehicle, and benznidazole at 30 and 100 mg kg^-1.

The fits correspond to the intercept and slopes in Table 1. The reactivity of (A) IBAG38 and (B) IBAG39 remains stable in mice treated with vehicle and benznidazole at 30 mg kg-1 and sharply decreases in 100 mg kg-1 benznidazole treated mice. (C) IBAG257 declines in reactivity in the three groups. The reactivities of (D) IBAG36, (E) IBAG37 and (F) IBAG101 increase only in vehicle-treated animals. The vertical axis is representative for the real intensity of the IBAGs.</p