Pattern Recognition Receptors (PRRs)

Pattern recognition receptors (PRRs) play a very important role in the innate immune response by identifying the core structures called as pathogen associated molecular patterns (PAMPs) distinctive to each pathogen and these obligatory structures are also required for the survival of pathogens. PRRs play a vital role by recognizing PAMPs which are distinct to each pathogen, and are fundamental molecular structures required for the pathogens survival. PRRs are mainly expressed by macrophage and dendritic cells and determine assorted group of pathogens. They activate pro-inflammatory signaling pathways, stimulate phagocytic responses or bind to micro-organisms as secreted proteins. When our body senses that it is under attack the innate immune system gets activated. This is because our body recognizes alarm signals generated by two pathways. First is the exogenous alarm signals which are generated by invading microorganisms and are collectively known as PAMPs. Whereas the endogenous alarm signals are produced by dead and dying cells and are called as damage-associated molecular patterns (DAMPs) which are excreted or released by dead, dying and damaged cells. The PRRs recognize DAMPs and PAMPs and activate the innate immune system. Recent studies reveal that the innate immune system has a greater specificity and is highly developed in its ability to discriminate between self and foreign. These responses are not only essential for early pathogen recognition, but are also involved in the activation and shaping of adaptive immunity.