Histology of mice footpads infected with <i>M. ulcerans</i>.

<p>Histological sections of footpads collected at different time points were stained with HE (A, B, E, F, H, I, L, M, P, Q, T and U) or ZN (C, D, G, J, K, N, O, R, S, V and X). Magnifications: ×10 (A, E, H, L, P and T), ×20 (C, G, J, N, R and V), ×60 (B, D, F, I, K, M, O, Q, S, U and X). (A and E) Footpads of control-infected and DEX mice before the beginning of RS treatment (12 days post-infection), showing necrotic areas (asterisks). Magnifications of panel A and E (rectangles) show neutrophils (B and F; arrows) and mononuclear cells (B; arrowheads) adjacent/in necrotic areas. (C and G) Staining for bacteria in necrotic areas and (D) is a magnification of panel C. (H, L, P and T) Footpads of control-infected and DEX mice with 4 and 10 weeks of RS (42 and 82 days post-infection) show abundant cellular infiltration, composed mainly by mononuclear cells (I, M, Q and U; arrowheads). (J, N, R and V) Staining for bacteria in the same tissue areas and magnifications of the bacilli are shown in panels K, O, S and X. w, weeks; dpi, days post-infection.