Aggregation of Human Platelets by .

CONTEXT

Periodontitis is a persistent infection of the tissues surrounding the teeth characterized by inflamed microvasculature, and is associated with increased systemic platelet activation.

AIMS

The purpose of this study was to assess the platelet aggregating potential of the red-complex bacterium . A second-related objective was to ascertain the effect of dual platelet inhibitors on -platelet interaction.

SETTINGS AND DESIGN

These experiments were done in a basic science laboratory combining isolated human platelets with isolated bacterial cells.

METHODS

Dilutions of cells were counted by quantitative polymerase chain reaction. Aggregation was assayed in a platelet aggregometer after adding cells or sonic extracts to gel filtered platelets, some of which were preincubated with the dual platelet inhibitors aspirin plus clopidogrel.

RESULTS

Platelets aggregate when exposed to cells or sonic extracts and dilution results in increased lag times and decreased aggregation. Platelets preincubated with the combination of aspirin plus clopidogrel do not aggregate in response to .

CONCLUSIONS

Within the limitations of this study, cells aggregate human platelets and the activity can be attenuated by diluting the cells and blocked by the combination of aspirin plus clopidogrel.