Experimental reproduction of the Jorge Lobo's disease in BAlb/c mice inoculated with Lacazia loboi obtained from a previously infected mouse.

Abstract

Long-term maintenance of Lacazia loboi in the laboratory has not been reported. We report here the use BALB/c mice to maintain the Lacazia loboi for extended period of time. Eight to ten week-old mice were inoculated intradermally in both hind footpads with a fungal suspension from a macerated footpad obtained from an original mouse previously infected with the fungi and sacrificed 8 months after inoculation. The inoculated animals were sacrificed at different time intervals, footpads were excised, the right one was submitted to histopathological examination and the left one was macerated in sterile saline for fungal count and viability index determination. The inoculated animals presented the histopathological picture identical to the mice previously inoculated with material from human lesion. Granulomatous infiltrates with predominance of macrophages and giant cells were observed. The granulomas evolved progressively as observed in the different times of sacrifice. After 7 months of inoculation, macroscopic lesions were observed, and the number of fungi obtained from macerated footpads was higher than the number of inoculated fungi. The pattern of lesion development was similar to what was observed in animals infected with a fungal suspension obtained from a human lesion. Considering the histopathological findings, the clinical manifestations, and the finding of a higher number of fungi obtained than the inoculated into footpads of each mice, we believe the BALB/c mice strain is as an excellent way to maintain L. loboi in laboratory. Moreover, even after serial passages of the fungi, the granulomatous lesions are reproduced consistently in laboratory conditions.