Inoculation of Lacazia loboi into the subcutaneous tissue of the hamster cheek pouch

• Main Authors: Diltor Vladimir Araujo OPROMOLLA, Maria Esther Salles NOGUEIRA
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 2000
• Subjects: Lacazia loboi; Granuloma; Cheek Pouch; Hamster; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doaj.org/article/8c47ad7941ba494e81a856879538ecf7

The subcutaneous tissue of the hamster cheek pouch, a site of immunologic privilege, has been used to investigate the potential infectivity of different types of parasites. It has been demonstrated that the implantation of fragments of lesions induced by the fungus Lacazia loboi, the etiologic agent of Jorge Lobo's disease, into the subcutaneous tissue of the hamster cheek pouch resulted in parasite multiplication and dissemination to satellite lymph nodes16. Here we describe the evolution of lesions induced by the inoculation of the isolated fungus into this immunologically privileged site. The morphology of the inflammatory response and fungal viability and proliferation were evaluated. Inoculation of the fungus into the cheek pouch induced histiocytic granulomas with rare lymphocytes. Although fungal cells were detected for a period of up to 180 days in these lesions, the fungi lost viability after the first day of inoculation. In contrast, when the parasite was inoculated into the footpad, non-organized histiocytic lesions were observed. Langhan's giant cells, lymphocytes and fungal particles were observed in these lesions. Fungal viability was observed up to 60 days after inoculation and non-viable parasites were present in the persistent lesions up to 180 days post-inoculation. These data indicate that the subcutaneous tissue of the hamster cheek pouch is not a suitable site for the proliferation of Lacazia loboi when the fungus isolated from human tissues is tested.