Treatment with CL429 enhances leptospiral clearance in the acute but not the chronic phase of infection.

A) Chronogram of the experiment. C57BL/6 WT mice were injected IP with 200 μL PBS containing 2.5% DMSO (vehicle) or 25 μg CL429 2 and 1 weeks before IP infection. B) C57BL/6 WT treated mice (n = 5) were IP infected with 5x107 leptospires, and weight variation monitoring, expressed as a percentage versus of the weight on the day of infection, was used to follow the severity of acute infection. C) Live imaging of albino (C57BL/6 B6(Cg)-Tyrc-2J/J) treated mice IP infected with a sublethal dose of 5x107 bioluminescent L. interrogans serovar Manilae bioluminescent strain MFlum1. During the acute phase of infection, mice were daily imaged (ventral view) from day 0 (30 minutes post-infection) to day 4. During the chronic phase from day 8, mice were imaged in the dorsal view to measure renal colonization. The lower panel shows a representative example of the follow-up of one mouse. The upper panel shows the quantification of data from n = 4 mice. The blue to red scale is proportional to the intensity of bioluminescence, reflecting the number of live leptospires. Data represent 1 of 2 independent experiments (n = 4 or 5). Curve comparison was performed by 2-way ANOVA comparing PBS vs clodronate at each corresponding time point. * p-value p-value p-value < 0.001.