TLR2 and atherosclerosis: P. gingivalis can directly interact with Toll-like receptor 2 (TLR2) to initiate inflammatory signaling such as the nuclear factor-κB (NF-κB) pathway, which is associated with caspase-dependent apoptosis and atherosclerotic progression.10,17,29 Analysis of human early (n = 13)- and advanced (n = 16)- plaques by RNA-seq showed that TLR2 expression was significantly higher in advanced plaques, suggesting the potential role of TLR2 activation in promoting atherosclerosis (Fig. S4a).