Efficiency of gold nanoparticles coated with the antimicrobial peptide indolicidin against biofilm formation and development of Candida spp. clinical isolates

Abstract

Elisabetta de Alteriis,1 Valeria Maselli,1 Annarita Falanga,2 Stefania Galdiero,2 Federica Maria Di Lella,3 Renato Gesuele,1 Marco Guida,1 Emilia Galdiero1 1Department of Biology, University of Naples “Federico II”, Naples, Italy; 2Department of Pharmacy, University of Naples “Federico II”, Naples, Italy; 3Section of Microbiology and Virology, University Hospital “Luigi Vanvitelli” of Naples, Naples, Italy Background: This article examines the use of a novel nano-system, gold nanoparticles coated with indolicidin (AuNPs–indolicidin), against pathogenic Candida albicans biofilms. Candida species cause frequent infections owing to their ability to form biofilms, primarily on implant devices. Materials and methods: We used an integrated approach, evaluating the effect of AuNPs-indolicidin on prevention and eradication of Candida biofilms formed in multi-well polystyrene plates, with relative gene expression assays. Four biofilm-associated genes (FG1, HWP1, ALS1 and ALS3, and CDR1 and CDR2) involved in efflux pump were analyzed using reverse transcription polymerase chain reaction. Results: Treatment with the nano-complex significantly inhibits the capacity of C. albicans to form biofilms and impairs preformed mature biofilms. Treatment with AuNPs–indolicidin results in an increase in the kinetics of Rhodamine 6G efflux and a reduction in the expression of biofilm-related genes. Conclusion: These data provide a chance to develop novel therapies against nosocomially acquired refractory C. albicans biofilms. Keywords: antimicrobial activity, anti-biofilm activity, fungal biofilm, drug resistance, fungal infections

Keywords

• antimicrobial activity
• antibiofilm activity
• fungal biofilm
• drug resistance
• fungal infections