The fungal genus Fonsecaea comprises etiological agents of human chromoblastomycosis, a chronic implantation skin disease. The current hypothesis is that patients acquire the infection through an injury from plant material. The present study aimed to evaluate a model of infection in plant and animal hosts to understand the parameters of trans-kingdom pathogenicity. Clinical strains of causative agents of chromoblastomycosis (Fonsecaea pedrosoi and Fonsecaea monophora) were compared with a strain of Fonsecaea erecta isolated from a living plant. The clinical strains of F. monophora and F. pedrosoi remained concentrated near the epidermis, whereas F. erecta colonized deeper plant tissues, resembling an endophytic behavior. In an invertebrate infection model with larvae of a beetle, Tenebrio molitor, F. erecta exhibited the lowest survival rates. However, F. pedrosoi produced dark, spherical to ovoidal cells that resembled muriform cells, the invasive form of human chromoblastomycosis confirming the role of muriform cells as a pathogenic adaptation in animal tissues. An immunologic assay in BALB/c mice demonstrated the high virulence of saprobic species in animal models was subsequently controlled via host higher immune response.

No abstract

No abstract

No abstract

Populational studies involve single individual DNA extraction in order to grant further genotyping data. In the case of some parasitic nematodes, the reduced dimensions and high individual number per infestation makes individual genotyping a difficult task. Aiming the development of a protocol we performed adjustments in available methods in order to acquire the best gain in purity and concentration of genomic DNA. Single specimens were digested in Worm Lysis Buffer and submitted to PCR amplification as a concept test. It was possible to obtain good amount and concentration of DNA from individuals. Quality was sufficient to grant subsequent ITS1 sequencing.