Introduction: CD40 and its ligand participate in atherosclerosis formation, progression and destabilization. Increased soluble CD40 ligand (sCD40L) was observed in hypercholesterolemia, unstable angina and conditions with platelet activation. To date, there is no report on the association of sCD40L with angiographic peripheral artery disease (PAD) disease severity.
Materials and methods: From March 1999 to April 2004, consecutive patients having angiographically documented PAD and given consents for pre-procedural serum sample use were recruited into this study. The key PAD lesions should be > or = 70% diameter stenotic at the lower limbs and patients were dichotomized into two groups depending on total PAD lengths. Peer angiographic control subjects were those free of coronary disease, PAD and major medical diseases. The serum samples were thawed and analyzed for sCD40L, monocyte chemotactic protein 1 (MCP-1) and hs-CRP in a single batch.
Results: A total of 63 well-defined lower-limb PAD patients and 30 control subjects were studied. Patients with PAD lengths >5 cm (N=38) presented higher sCD40L than those with lesions < or = 5 cm (N=25) (5430+/-459 vs. 3889+/-507 pg/ml, p=0.037) and control subjects (5430+/-459 vs. 3973+/-551 pg/ml, p=0.037). However, there was no significant difference in circulating MCP-1 (375+/-49 vs. 310+/-49 pg/ml and 297+/-24 pg/ml, respectively, p=0.371) or hs-CRP (0.64+/-0.16 vs. 0.51+/-0.15 mg/ml and 0.46+/-0.15 mg/dl, respectively, p=0.682) across three groups. PAD patients with associated coronary lesions did not differ in circulating CD40L, MCP-1 or hs-CRP from without and control subjects.
Conclusions: Soluble CD40L was significantly elevated in patients with more advanced symptomatic PAD and might be an indicator for disease extent stratification. The distribution of sCD40L in PAD was not affected by coronary involvement or not.