The increased prevalence and severity of periodontitis observed in diabetes mellitus (DM) has been partially attributed to an exaggerated monocyte response to microbial challenge. Tissue factor (TF) is a cell surface-bound glycoprotein receptor expressed by monocytes with procoagulant and proinflammatory functions.

Objective: To determine the association among a diagnosis of DM, a diagnosis of periodontitis, and monocyte TF gene expression.

Methods: A total of 46 subjects received a complete periodontal examination; 18 with a diagnosis of DM (4 T1DM and 14 T2DM) and 28 systemically healthy controls. A diagnosis of periodontitis was based on a threshold of at least 4 sites with loss of attachment of at least 5 mm and probing depths of at least 5 mm. A peripheral blood sample was obtained from each subject and total RNA was immediately isolated and stored at -80°C. Gene specific primers were used with RT-PCR to measure expression of TF mRNA with b-actin used as a normalizer. TF and b-actin had similar dynamic reaction ranges and therefore the comparative C_T method was used for quantitative comparison.

Results: TF gene expression did not differ significantly in subjects with and without a diagnosis of DM (comparative expression level 1.04, p=0.887), but was approximately 25% higher in subjects with a diagnosis of periodontitis (comparative expression level of 1.24); however this value did not reach significance (p=0.380).

Conclusion: The results of this study suggest that monocyte TF gene expression is increased in subjects with a diagnosis of periodontitis independent of a diagnosis of DM. This work was supported by NIH K23 RR-16106-03 and GCRC M01-RR00211.