Aim: To investigate whether the increasing CD40-CD40 ligand system is related to restenosis in patients after percutaneous coronary intervention (PCI).
Methods: Twenty normal controls and 120 patients with PCI were investigated. The expression of CD40 and the CD40 ligand (CD40L) on platelets was analyzed by indirectimmunofluorescence flow cytometry. The serum level of soluble CD40L (sCD40L) and C-reactive protein (CRP) was determined by commercially available enzyme linked immunosorbent assay. Restenosis was observed in 120 patients within a 6 month follow-up period after PCI surgery.
Results: Restenosis occurred in 29 patients (24.2%). Patients who developed restenosis showed higher levels of CD40-CD40L system compared with non-restenotic patients before PCI. All restenotic patients showed a significant increase in CD40 [66.9 +/-4.8, mean fluorescence intensity (MFI)] and CD40L (14.9 +/-1.8, MFI) co-expression on platelets as well as sCD40L (13.7 +/-1.7 ng/mL) compared with non-restenotic patients and controls during the 6 month follow-up period (P<0.01). Elevated sCD40L and CD40L were significantly correlated with the serum level of CRP after percutaneous transluminal coronary angioplasty and with lumen loss during the 6 month followup period.
Conclusion: The level of CD40L was associated with late restenosis after PCI indicating that restenosis is an inflammatory disorder.