Posters

Comparative in vitro model of biofilm formation by keratitis-associated fungal pathogens

Poster Details

First Author: S. Saha INDIA

Co Author(s):    J. Sengupta   A. Khetan   D. Chatterjee   D. Banerjee           

Abstract Details

Purpose:

To demonstrate the comparative in vitro ability of biofilm formation on soft contact lens and amniotic membrane for antifungal susceptibility pattern of three keratitis associated fungal pathogens- Aspergillus fumigatus, Fusarium solanii, Alternaria sp and Candida albicans.

Setting:

Tertiary care eye hospital of eastern India

Methods:

Fungal species were collected from mature solid culture plate and mixed with RPMI and incubated for 24 hrs for relevant turbidity. To evaluate the biofilm formation of all isolates, soft contact lenses and amniotic membranes were submerged in 96 wells, polystyrene plates containing medium, inoculated with 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. A semi quantitative measure of biofilm formation was calculated by XTT reduction assay. Comparative minimum inhibitory concentration (MIC) and minimum biofilm eradication concentration (MBEC) were noted against antifungals.

Results:

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

Conclusions:

We established an in vitro model of fungal biofilm formation on contact lenses and amniotic membrane. Amniotic membrane shows less biofilm activity compare to contact lens. This in vitro model will be helpful for better understanding the pathogenesis of fungal keratitis.

Financial Disclosure:

NONE