TLR4 and atherosclerosis: Chen et al. reported that while atherosclerosis was significantly accelerated in C. pneumoniae-infected TLR4- and MyD88-positive mice, C. pneumoniae infection resulted in minimal effect on atherosclerosis progression in TLR4- and MyD88-deficient mice [25], indicating the importance of the TLR4/MyD88 pathway in C. pneumoniae-mediated atherosclerosis.