Comparison of the cell walls of Paracoccidioides loboi and Paracoccidioides brasiliensis by using polysaccharide-binding dyes.

Biopsies from patients with Jorge Lobo's disease (keloid blastomycosis) and paracoccidioidomycosis (South American blastomycosis), caused respectively by Paracoccidioides loboi a non-cultivated fungus and Paracoccidioides brasiliensis, were stained with six different dyes having the property of forming complexes with some polysaccharides and oligosaccharides. The cell-walls of both fungi showed similar staining characteristics, suggesting a similar chemical structure. The role of the fungal cell-walls in evasion mechanisms is discussed.