58 Views

OR14 - Analysis of Interactions Between Candida Albicans and Enterococcus Faecalis in an Iron Rich Environment

Wednesday, May 3, 2023

1:15 PM – 1:30 PM CT

Location: E353A (Level 3)

Presenter(s)

LR

Luke Revelt, D.M.D.

resident
Temple University
Philadelphia, Pennsylvania

Disclosure information not submitted.

Co-Author(s)

RS

Rishabh Sharma, Ph.D.

Postdoctoral researcher
Temple University
Philadelphia, Pennsylvania

Disclosure information not submitted.
Maobin Yang, Ph.D.

Director, Postdoctoral Endodontic Program; Associate Professor
Temple University
Philadelphia, Pennsylvania

Disclosure information not submitted.
SP

Sumant Puri, Ph.D.

Co-director of the Oral Microbiome Research Laboratory; Associate Professor
Philadelphia, Pennsylvania

Disclosure information not submitted.

Objective: Failed root canal treatment (RCT) has been associated with various microorganisms, including bacteria such as Entercoccus faecalis and fungi such as Candida albicansE. faecalis and C. albicans may contribute to failed RCTs. Salivary iron levels vary among individuals and iron regulates virulence mechanisms of C. albicans. We analyzed the role of iron in the interactions between C. albicans and E. faecalis; specifically, the effect on cell aggregation, biofilm formation, and physical interaction between the two species.

Methods: Individual cultures of E. faecalis and C. albicans as well as co-culture were prepared in a mixture of brain heart infusion and RPMI media in high and low iron. Biofilm formation was assessed by crystal violet staining and recorded as optical density at 600 nm (OD₆₀₀). Data was analyzed using an unpaired t-test with significance level of p< 0.05. Sedimentation was measured by recording OD₆₀₀ of undisturbed cultures to measure cellular aggregation. Physical interactions were observed under the microscope.

Results: Biofilm formation was reduced in coculture under high iron compared to low iron conditions (mean OD₆₀₀ of 2.12 and 3.60, respectively; p< 0.0001). Further, under high iron conditions, threefold reduction in aggregation in coculture was observed, when compared with C. albicans alone. Microscopy showed limited physical interaction between E. faecalis and C albicans regardless of iron levels.

Conclusion: E. faecalis and C. albicans show an antagonistic relationship, particularly under high iron, as seen by a reduction in biofilm formation and cell aggregation.