Toll-like receptors (TLRs) are type I transmembrane signaling receptors characterized by containing leucine-rich repeats (LRR) extracellular domain and IL-1 receptor like intracellular domain. TLRs are responsible for recognizing pathogen-associated molecule patterns (PAMPs). They are primary sensors of both innate and adaptive immune systems. To date a total of 12 TLRs have been indentified. Toll-like receptor 2 (TLR2), known as CD282, is one of the important receptors. It is expressed on monocytes/macrophages, dendritic cells, granulocytes, endothelial and epithelial cells. By association with TLR1 or TLR6 and CD36, TLR2 is central to the innate immune response to diverse set of pathogens, including several components of Gram-positive bacteria such as peptidoglycan, lipoteihoic acid (LTA), lipoarabinomanan, lipoproteins, as well as different LPS from certain Gram-negative bacteria, yeast, spirochete and fungi. The T2.5 antibody reacts with both mouse and human TLR2. It is able to inhibit cell activation through blocking the interaction of TLR2 with its ligands.