Monocyte Expression of Toll-like Receptor-4 in Patients with Stable Angina Undergoing Percutanoeus Coronary Intervention

Background: Toll like receptors (TLRs) are well recognized players in inflammatory conditions. Among them TLR-4 is involved in chronic inflammatory processes such as formation of atherosclerotic plaques. Objective: The present study was aimed to examine the effects of percutanoeus coronary intervention (PCI) as a revascularization method on monocyte expression of hTLR-4 and on the serum levels of two proinflammatory cytokines (TNF-α and IL-1β). Methods: Blood samples were obtained from 41 patients with stable angina who were candidates for PCI. The samples were collected immediately before and 2h and 4h after PCI. The expression of hTLR-4 on CD14+ monocytes and the serum levels of TNF-α and IL-1β were measured using flowcytometry and ELISA techniques, respectively. Results: By comparing the frequency of circulating hTLR-4+/CD14+ monocytes at different time points, it was observed that PCI procedure up regulates the monocyte expression of hTLR-4 (p<0.05). The increase in expression was associated with the elevation of the serum levels of proinflammatory cytokines (p<0.05). There was a significant correlation between monocyte expression of hTLR-4 and serum levels of TNF-α and IL-1β only before PCI. In spite of parallel increase in the serum levels of proinflammatory cytokines and the monocyte expression of hTLR-4, the correlation did not attain a significant level after PCI intervals. Conclusion: PCI is positively associated with an increase in the monocyte expression of hTLR-4. It is also associated with the elevation in the serum levels of proinflmmatory cytokines. These findings suggest that hTLR-4 monocyte expression may be used as a potential prognostic tool in patients with stable angina undergoing PCI.