Posters

Architectural analysis of biofilm formation by keratitis-associated fungal pathogens

Poster Details

First Author: S.Saha INDIA

Co Author(s):    J. Sengupta   A. Khetan                 

Abstract Details

Purpose:

To demonstrate the in vitro ability of biofilm formation on soft contact lens, amniotic membrane and human corneal surface.

Setting:

Tertiary eye care center of eastern India

Methods:

Fungal species were collected from solid medium culture plate and mixed with liquid RPMI 1640 and incubated for 24 hrs to get relevant turbidity. To evaluate the biofilm formation of all isolates, soft contact lenses, amniotic membrane and cornea were submerged in 96 wells, flat bottom, polystyrene plates containing medium, inoculated with respective fungal strains. After 72 hrs lenses were removed and the planktonic cells were washed gently with buffer. The developed biofilms were then analyzed by fluorescence microscopy, Scanning electron microscopy (SEM) and phase contrast microscopy. A semi quantitative measure of biofilm formation was calculated by XTT reduction assay.

Results:

Fluorescence microscopy using concanavalin showed that all selected fungal species formed biofilms. Quantification data revealed that Candida albicans able to make a large amount of biomass after 72h incubation followed by Aspergillus fumigatus and Alternaria sp. The biofilm growth curve showed that all strains required minimum 6h in their developmental phase over soft contact lenses and showed very low metabolic activity in the first 12 hrs. Mature biofilm formation was observed within 72h incubation for all the strains.

Conclusions:

We established an in vitro model of three filamentous fungi and one yeast biofilm formation on different surfaces. Adhesion is playing an important role for biofilm formation which fully depends on surface material. This in vitro model will be helpful for better understanding the pathogenesis of fungal keratitis while they form biofilm on corneal surfaces.

Financial Disclosure:

None