A comparative serological study of the SsCBF antigenic fraction isolated from three Sporothrix schenckii strains.

A previous work showed that an antigenic fraction of Sporothrix schenckii, SsCBF, was specifically recognized by IgG antibodies present in patients' clinical specimens. The objective of this investigation was to compare the reactivity of this antigen recovered from three S. schenckii strains. ROC curve analysis revealed a variation in the sensitivity and specificity of the antigen derived from each of the strains, with a higher AUC for strain 1099-18. Moreover, the presence of the main O-glycosidically-linked epitopes described in the SsCBF fraction was ascertained. A significant reduction in SsCBF reactivity of all the strains was observed after beta-elimination confirming the presence of O-glycan epitopes. The antigen isolated from strain 1099-18 proved to be a more accurate diagnostic tool for serodiagnosis of sporotrichosis.