Expression of FcRs on monocytes among Kawasaki disease patients with coronary artery lesions.

Objective: To study expression of Fc gamma receptors (FcRs) on monocytes in Kawasaki disease (KD) patients with coronary artery lesions (CAL).

Methods: 160 newly diagnosed KD patients and 80 health children were enrolled in this study. All patients were scheduled to receive both aspirin and intravenous immunoglobulin (IVIG). Serial blood samples were obtained before and 3days after completing IVIG therapy. The first two-dimensional echocardiographic examination was performed for all KD patients within 10days, and was repeated at 3weeks. CAL was defined by coronary artery Z-scores≥2.5 by echocardiography. Expression of inhibitory and activating FcRs on CD14 monocytes (MCs) was assessed by flow cytometry. Cytokine expression in MC was evaluated by PCR.

Results: Of the 160KD patients enrolled in this study, 36 had coronary artery lesions (KD-CAL group), while 124 did not (KD-CAL group). There was no significant difference in FcRI expression on MCs from KD patients and that of Ctrls. Although FcRIII and FcRIIa levels were significantly higher in KD patients compared with those in Ctrls, there were no significant differences between the KD-CAL and KD-CAL groups. FcRIIb expression in the KD patients was lower than that of Ctrls, meanwhile expression in the KD-CAL group was lower than that in the KD-CAL group. After IVIG therapy, FcRIIb expression increased in KD-CAL, but did not reach the normal range. A negative correlation was observed between the levels of IL-6, TNF-α and FcRIIb expression.

Conclusion: Decreased FcRIIb expression on MCs may contribute to the development of coronary artery lesions in patients with KD.