Fig. 4

Recombinant human interleukin (IL)-35 stimulation to CD14⁺ monocytes induced human umbilical vein endothelial cells (HUVECs) death. CD14⁺ monocytes were purified from peripheral bloods of patients with Kawasaki disease (n = 8) and controls (n = 12). 10⁵ of CD14⁺ monocytes were co-cultured with 10⁵ of HUVECs in both direct and indirect contact manners. a CD14⁺ monocytes from controls induced increased target HUVECs death in both direct and indirect contact co-culture systems. There were no significant differences of target HUVECs death between direct and indirect contact co-culture system. b~e CD14⁺ monocytes from Kawasaki disease (n = 8) were stimulated with recombinant human IL-35 and 1 × lipopolysaccharide for 24 h. 10⁵ of IL-35-stimulated CD14⁺ monocytes were co-cultured in direct contact or in indirect contact with 10⁵ of HUVECs, in the presence or absence of etanercept (TNF antagonist) or Z-AAD-CMK (granzyme B inhibitor) stimulation. Etanercept treatment did not induced CD14⁺ monocytes-mediated target cell death or enhanced the suppression function of IL-35 stimulation in b direct contact or c indirect contact co-culture system. Z-AAD-CMK stimulation not only inhibited CD14⁺ monocytes-induced HUVECs death but also further dampened the suppression function of IL-35 in d direct contact and e indirect contact co-culture system. Tukey test was used for comparison. Individual level of each subject was shown. The horizon line presented mean, and error bar presented standard deviation