Biogenic selenium nanoparticles: characterization, antimicrobial activity and effects on human dendritic cells and fibroblasts.
Tailored nanoparticles offer a novel approach to fight antibiotic-resistant microorganisms. We analysed biogenic selenium nanoparticles (SeNPs) of bacterial origin to determine their antimicrobial activity against selected pathogens in their planktonic and biofilm states. SeNPs synthesized by Gram-negative Stenotrophomonas maltophilia [Sm-SeNPs(-)] and Gram-positive Bacillus mycoides [Bm-SeNPs(+)] were active at low minimum inhibitory concentrations against a number of clinical isolates of Pseudomonas aeruginosa but did not inhibit clinical isolates of the yeast species Candida albicans and C. parapsilosis. However, the SeNPs were able to inhibit biofilm formation and also to disaggregate the mature glycocalyx in both P. aeruginosa and Candida spp. The Sm-SeNPs(-) and Bm-SeNPs(+) both achieved much stronger antimicrobial effects than synthetic selenium nanoparticles (Ch-SeNPs). Dendritic cells and fibroblasts exposed to Sm-SeNPs(-), Bm-SeNPs(+) and Ch-SeNPs did not show any loss of cell viability, any increase in the release of reactive oxygen species or any significant increase in the secretion of pro-inflammatory and immunostimulatory cytokines. Biogenic SeNPs therefore appear to be reliable candidates for safe medical applications, alone or in association with traditional antibiotics, to inhibit the growth of clinical isolates of P. aeruginosa or to facilitate the penetration of P. aeruginosa and Candida spp. biofilms by antimicrobial agents.
Department of Diagnostic and Public Health, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy.
Eleonora
E
Cremonini
Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
Emanuele
E
Zonaro
Department of Medicine, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy.
Marta
M
Donini
Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
Silvia
S
Lampis
Department of Diagnostic and Public Health, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy.
Marzia
M
Boaretti
Department of Medicine, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy.
Stefano
S
Dusi
Cystic Fibrosis Regional Center, AOUI Verona, Verona, Italy.
Paola
P
Melotti
Department of Diagnostic and Public Health, University of Verona, Strada Le Grazie 8, 37134, Verona, Italy. maria.lleo@univr.it.
Maria M
MM
Lleo
Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy. giovanni.vallini@univr.it.
Giovanni
G
Vallini
D000890:Anti-Infective Agents / Q000378:metabolism* / Q000633:toxicity; D001407:Bacillus / Q000378:metabolism*; D018441:Biofilms / Q000187:drug effects; D002175:Candida / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000187:drug effects* / Q000502:physiology; D005347:Fibroblasts / Q000187:drug effects* / Q000502:physiology; D008826:Microbial Sensitivity Tests; D053758:Nanoparticles / Q000378:metabolism* / Q000633:toxicity; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D012643:Selenium / Q000378:metabolism* / Q000633:toxicity; D020615:Stenotrophomonas maltophilia / Q000378:metabolism*
D000890:Anti-Infective Agents; D016207:Cytokines; D017382:Reactive Oxygen Species; D012643:Selenium