The correlation of virulence, pathogenicity, and itraconazole resistance with SAP activity in Candida albicans strains

Abstract

The relationship between SAP2 activity and drug resistance in Candida albicans was investigated by using itraconazole-resistant and itraconazole-sensitive C. albicans isolates. The precipitation zones were measured to analyze SAP2 activity. Mice were classified into itraconazole-resistant and -sensitive C. albicans isolate groups, and a control group, with their survival and mortality rate being observed over 30 days. The relative expression levels of CDR1, CDR2, MDR1, and SAP2 were measured using RT-PCR. It was found that the secreted aspartyl proteinase activity of itraconazole-resistant C. albicans strains was significantly higher than that of itraconazole-sensitive C. albicans strains (P < 0.001). A significantly higher mortality rate was recorded for mice treated with itraconazole-resistant C. albicans than for mice treated with itraconazole-sensitive C. albicans. In regards to the CDR1, CDR2, and MDR1 genes, there was no significant difference between the 2 groups of mice. Positive correlations between SAP2 and MDR1 and between CDR1 and CDR2 were found. The high expression level of SAP2 may relate to the virulence, pathogenicity, and resistance of C. albicans.

Keywords: Candida albicans; pathogenicity; pathogénicité; protéinase aspartique sécrétée (SAP); resistance; résistance; secreted aspartyl proteinase (SAP); virulence.