Pattern Recognition, Toll-Like Receptors: Mechanisms and Implications in Lung Injury and Pulmonary Medicine

Toll-like receptor (TLR) is a clan of receptor proteins that belong to a group of receptors called pattern recognition receptors or PRRs. These receptors are present in a variety of immune and non-immune cells and help the cell recognize unique Pathogen-associated molecular patterns (PAMPs), such as the bacterial lipopolysaccharide, viral nucleic acid etc., and Damage-associated molecular patterns (DAMPS) from dying or injured host cells. TLRs respond to these pathogenic stimuli (PAMPS/DAMPs) and relay signal into the interior of the cell with the help of adaptor proteins (MyD88, TRIF etc.) and generate an initial immune response against the invading pathogen or a stimulus.