Crossed-antigenicity between the etiologic agents of lobomycosis and paraccocidioidomycosis evidenced by an immunoenzymatic method (PAP).

: Lobomycosis or Keloidal blastomycosis and Paracoccidiodomycosis found in South American tropical regions are considered different mycoses from the clinical and mycological point of view. Very little is known about the immunology of Lobomycosis, since the etiological agent of this mycosis, Loboa loboi, is not cultured "in vitro". In order to overcome this difficulty, a rabbit Paracoccidioides brasiliensis, antiserum is usually used, since crossed-antigenicity between both fungi has been demonstrated by serological methods and immunofluorescence. In this paper, common antigens between Loboa loboi and Paracoccidiodes brasiliensis were detected by means of rabbit serum against a metabolic antigen from Paracoccidiodies brasiliensis and using a peroxidase-antiperoxidase (PAP) technique. This method provided retrospective studies on three cases studied by using histological material from Lobomycosis stocked for a long time. The antigenic relationship between both fungi was confirmed by our results based on biopsies from Keloidal blastomycosis and Paracoccidioidomycosis, by using the PAP method and a rabbit serum against a metabolic antigen from Paracoccidioides brasiliensis.