Toll Like Receptor 2 (TLR2) Cascade

TLR2 is involved in recognition of peptidoglycan from gram-positive bacteria, bacterial lipoproteins, mycoplasma lipoprotein and mycobacterial products. It is quite possible that recognition of at least some other TLR2 ligands may be assisted by additional accessory proteins, particularly in association with TLR1 or TLR6. TLR2 is expressed constitutively on macrophages, dendritic cells, and B cells, and can be induced in some other cell types, including epithelial cells. TLR1 and TLR6, on the other hand, are expressed almost ubiquitously (Muzio et al. 2000). TLR2 may be a sensor and inductor of specific defense processes, including oxidative stress and cellular necrosis initially spurred by microbial compounds.

TLR2 在革兰氏阳性菌肽聚糖、细菌脂蛋白、支原体脂蛋白和结核杆菌产物识别中发挥重要作用。存在可能性，即至少某些其他TLR2配体的识别可能通过额外的辅助蛋白得到协助，尤其是在与TLR1或TLR6的关联中。TLR2在巨噬细胞、树突状细胞和B细胞上恒定表达，并可诱导于其他一些细胞类型，包括上皮细胞。另一方面，TLR1和TLR6在几乎所有细胞类型中几乎普遍表达（Muzio等，2000年）。TLR2可能是一种传感器和特定防御过程的诱导者，包括由微生物化合物最初激发的氧化应激和细胞坏死过程。