TLR4 and periodontitis: Yang et al. (2016) revealed that 5μg/ml LPS can upregulate CD14 gene expression in alveolar macrophages (AM). Hu et al. (2020) found that TLR4 and CD14 mRNA and protein expressions were upregulated in the peripheral blood mononuclear cells (PBMC) and cerebral cortex of rats with periodontitis established by gingival sulcus injection of P. gingivalis-LPS, and could be reversed by TAK-242.