Abstract 473: The Association of Bacterial Biofilms With Carotid Atherosclerotic Disease: A Study in Progress
Background: There is evidence to support that bacteria present in atherosclerotic plaque may play a role in disease pathogenesis. Several studies utilizing antibiotics to inhibit progression of atherosclerotic disease have been unsuccessful. Biofilms are complex microenvironments of bacterial colonies encased within a matrix that firmly adheres to surfaces. They exhibit extensive genotypic and phenotypic diversity and are 100 to 1000 times more resistant to antibiotics than planktonic cultures. We hypothesized that bacterial biofilms are present in carotid atheroma.
Methods: The IBIS Biosensor- Florescent in situ hybridization (FISH) pipeline for microbial discovery was applied to atherosclerotic samples obtained from 8 patients who underwent open CEA at Allegheny General Hospital. The extracted nucleic acid from CEA samples were aliquoted into wells of a microtiter plate containing broad range primers for PCR. The products were desalted in a 96-well plate format, sequentially electrosprayed into a mass spectrometer and the spectral signals processed to determine the masses of each of the PCR products present. The base composition of each amplicon was therefore unambiguously deduced. Using combined base compositions from multiple PCRs; the identities of the pathogens and their relative concentrations in the starting sample were determined. FISH using fluorescent probes targeted to the 16s rRNA, designed for each sample based on the result from the IBIS, was then performed. Confocal microscopy of the FISH stained samples allowed visualization of the specific bacterial species.
Results: One or more bacterial species were present in four of the eight CEA samples analyzed (50%). Species present were Staphylococcus capitis/ caprae, Staphylococcus warneri, Propionibacterium acnes, and Staphylococcus epidermidis. Further analyses in an attempt to correlate these findings with oral microbiota, dental and clinical history is currently ongoing.
Conclusion: In our ongoing study 50% of analyzed carotid atherosclerotic samples contained the highly antibiotic resistant bacterial biofilms. Mechanisms of biofilm formation in atheroma need to be explored.
Author Disclosures: T.B. Smith: None. L. Hiller: None. L. Nistico: None. R. Kreft: None. S. Bhashyam: None. G. Suero: None. K. Rayl: None. K. Driscoll: None. B. Chess: None. M. Passineau: None. D. Lasorda: None.
- © 2014 by American Heart Association, Inc.