ANTIGENIC SIMILARITIES TO PARACOCCIDIOIDES-BRASILIENSIS IN THERMO-DEPENDENT DIMORPHIC FUNGI ISOLATED FROM SOIL IN BOTUCATU, SP, BRAZIL

We compared the antigenic characteristics of two thermo-dependent dimo rphic fungi isolated from soil in Botucatu, an endemic area of paracoc cidioidomycosis (PCM) and Paracoccidioides brasiliensis. The soil isol ates grew as cerebriform colonies at 37 degrees C (yeast form) and as cottonous colonies at 25 degrees C (mycelial form). No pathogenicity f or ddY mice or hamsters were observed. In immunodiffusion test, there were precipitation bands between the 2 soil isolates and pooled PCM pa tient sera. There were also common precipitation bands at 21, 50 and 5 8 kDa between the soil isolates antigens and PCM patient sera by Weste rn-blotting, but no gp43 kDa band. No gene for gp43 kDa protein was de tected in the soil isolates by PCR. The fact that these isolates were obtained from an endemic area of PCM and there were some antigenic sim ilarities between the soil isolates and P. brasiliensis in immunodiffu sion test and Western-blotting may have some importance in epidemiolog ical surveys done with paracoccidioidin as well interfering with the i mmune response of the exposed population.