Association of Toll-like receptor 2-positive monocytes with coronary artery lesions and treatment nonresponse in Kawasaki disease

Kang, Soo Jung; Kim, Nam Su

In the acute stage of KD, the number of peripheral blood CD14+ monocytes increases 9) . Immunopathogenesis of KD involves sys temic inflammation, and activated monocytes have an important role in the production of proinflammatory cytokines, such as tu mor necrosis factor alpha (TNFα) and interleukins 1β and 6 (IL 1β and IL6, respectively) 911) . Activation of CD14+ monocytes initiates the activation of Tolllike receptors (TLRs), which are coreceptors of CD14 expressed on monocytes 12) . Activation of TLRs can trigger activation of nuclear factorkappa B (NFκB), the ubiquitous transcription factor that controls production of TNFα, IL1β, and IL6, leading to a massive systemic immune response and causing high fever 1215) . Among the TLRs, the role of TLR2 in CAL development in KD has been previously studied using a mouse model of coronary arteritis 16, 17) . By using the Lactobacillus casei cell wall extract (LCCWE)induced mouse model of coronary arteritis, it has been shown that via TLR2 pathway, along with myeloid differentiating factor 88, the macro phages and dendritic cells are activated by LCCWE 16) , resulting in the production of inflammatory cytokines, such as IL1β 18) .