MUKHERJEE PK, CHANDRA J, LEIDICH SD, ECKERT RL, GHANNOUM MA; Interscience Conference on Antimicrobial Agents and Chemotherapy.
Abstr Intersci Conf Antimicrob Agents Chemother Intersci Conf Antimicrob Agents Chemother. 2000 Sep 17-20; 40: 362.
Case Western Reserve Univ., Cleveland, OH
Candida albicans (CA) is the main fungal pathogen causing cutaneous candidiasis (CC). Although phospholipase B (Plb1), integrin-like protein (Int1) and secreted aspartyl proteinase (Sap1) are candidal virulence factors important to the development of disseminated candidiasis, their role in CC are unknown. Therefore, in this study, we investigated the abilities of CA strains deleted for PLB1, INT1 or SAP1 genes, to damage and migrate across human keratinocyte monolayers (HKM). Damage to HKM was measured using a tetrazolium salt (XTT)-based assay in which metabolically active cells reduce XTT to a colored formazan product. HKM were pretreated (5h) with culture supernatant (CS) from the respective deletion mutant, exposed to XTT and the level of formazan product determined at 490 nm. For migration studies, HKM grown on filter supports were inoculated with 1 x 10[6] yeast cells. Aliquots from the albuminal side were removed at 8h and subjected to quantitative culturing. HKM incubated with CS from Plb1+ cells produced significantly lower levels (OD[490] = 0.043+/-0.016) of formazan product than HKM incubated with CS from Plb1- cells (OD[490] = 0.07+/-0.001 P <0.01), indicating higher damage by the Plb1+ supernatant. CS from the Int1- and Sap1- mutants caused damage similar to the CS from Plb1+ cells (OD[490] = 0.043+/-0.004 and 0.048+/-0.014 for Int1- and Sap1-, respectively). The ability of only Plb1- cells to migrate across HKM was significantly reduced (11.0+/-2.0 CFU/ml, P <0.03) as compared to the Plb1+, Int1- and Sap1- cells (3.2+/-0.5x10[3], 3.5+/-0.6x10[3] and 1.0+/-0.01x10[5] CFU/ml for Plb1+, Int1- and Sap1-, respectively). Our results suggest that the Plb1p contributes to CC by both damage to- and migration across keratinocytes, while Sap1p and Int1p may be acting via other pathways.KEYWORDS: Cutaneous candidiasis; Keratinocytes; Phospholipase B
Publication Types:
Keywords:
- Animals
- Aspartic Endopeptidases
- Candida
- Candida albicans
- Candidiasis
- Candidiasis, Cutaneous
- Fungal Proteins
- Humans
- Lysophospholipase
- Proteins
- Saccharomyces cerevisiae
- Saccharomyces cerevisiae Proteins
Other ID:
UI: 102248081
From Meeting Abstracts