DIFFERENTIAL SUSCEPTIBILITY OF YEAST AND HYPHAL FORMS OF CANDIDA-ALBICANS TO PROTEOLYTIC ACTIVITY OF MACROPHAGES

The dimorphic transition of Candida albicans from the yeast Ol-Candida ) to the hyphal (H-Candida) form is a complex event whose relevance in fungal pathogenicity is still poorly understood. Using a cloned macro phage (M phi) cell line (ANA-1), we have previously shown that a M phi can discriminate between the two fungal forms, eliciting different se cretory responses. In the present study, we investigated the susceptib ility of Y-Candida and H-Candida to M phi proteolytic activity. In par ticular, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) techniques were employed to analyze the pat terns of lyticase proteinaceous extracts from cell walls of Y-Candida and H-Candida which had been unexposed or exposed to ANA-1 M phi s for 3 h. Silver staining allowed detection of a complex protein pattern i n both forms of C. albicans, qualitatively and quantitatively differin g from each other, mainly at molecular masses below 106 kDa. Western b lot staining with anti-C. albicans mannan antibodies and convalescent- phase sera of mice previously infected systemically or intracerebrally with C. albicans showed that, after contact with M phi s, Y-Candida b ut not H-Candida proteinaceous cell wall components are profoundly mod ified, with substantial reduction and/or disappearance of many bands. Our experimental approach provides initial insights into the different ial susceptibility of Y-Candida and H-Candida to the proteolytic activ ity of M phi s.