Fig 1.
Histopathological investigation of leptospiral infection and biofilm formation in kidney serial sections of wild Rattus norvegicus naturally infected with pathogenic Leptospira interrogans.
(A) Alcian Blue (AB) positively stained renal tubules (red arrows) observed in light turquoise blue, indicating the presence of biofilm matrix; insert B with detail of biofilm staining. (C) Renal tubules positive for IHC anti-L. interrogans demonstrating leptospiral colonization of proximal tubules (black arrows); insert D with detail of colonized tubule. Note that the serial sections showed in A and D are from the same region of one rat kidney, evidencing the co-localization of tubules concomitantly positive in AB (red arrows) and IHC (black arrows). Magnification, x 200.
Table 1.
Demographic characteristics, patterns of renal colonization and Leptospira shedding in wild Rattus norvegicus (Norway rats) positive for Leptospira infection and renal biofilm.
Table 2.
Histopathological alterations observed in chronically infected Rattus norvegicus with the presence of renal biofilm.
Fig 2.
Scanning electron microscopy (SEM) of leptospiral renal biofilm and its matrix in wild naturally colonized Rattus norvegicus.
A and B–SEM of colonized kidney with ruthenium red (RR) showed Leptospira agglomerates (white arrows) surrounded by an anionic exopolysaccharidic matrix (red arrows) inside the renal tubules. C and D–SEM of colonized kidney without RR, where leptospires are evidenced agglomerated (C) or isolated (D), without the presence of the matrix. E–SEM using RR of R. norvegicus negative control. F–SEM without RR of R. norvegicus negative control.
Fig 3.
Patterns of kidney colonization marking of naturally infected Rattus norvegicus.
Immunohistochemical representative images of kidney with (A) high intensity of colonized tubules (CTs); (B) low intensity of CTs; (C) partial to complete pattern of CT lumen occlusion; (D) marking restricted to the membrane of renal epithelium (partial occlusion); (E) agglomerated CTs distributed in the renal cortex; (F) isolated CTs distributed in the cortex. A, B, C and D: magnification, x 400. E and F: magnification, x 200.
Table 3.
Demographic characteristics, patterns of renal colonization and Leptospira shedding in wild Rattus norvegicus (Norway rat) naturally infected.