Comparative serological evaluation of 10 Blastomyces dermatitidis yeast phase lysate antigens from different sources.

Yeast phase lysate antigens from 10 isolates of Blastomyces dermatitidis (dog, ERC-2 and T-58; T-27, polar bear; woodpile, ER-3; bat lung, 48938; human, B5929, B5895, B5896, B5931, and CAPP) from different geographical regions, in addition to a Histoplasma capsulatum (G217B) lysate preparation were compared with respect to their reactivity against serum specimens from dogs, rabbits and humans positive for blastomycosis using an indirect enzyme-linked immunosorbent assay. In addition, the lysate antigens were also assayed against histoplasmosis-positive human serum samples to study their cross-reactivity. Variable results were obtained with T-58 and T-27 exhibiting the greatest reactivity. We also noticed that the lysate did not react consistently to serum samples across species with lesser reactivity evidenced when testing dog sera. Finally, T-58 gave the highest cross-reactivity with histoplasmosis-positive sera. The study may prove valuable in the development of antigen candidates for blastomycosis serodiagnosis.