BISC 101 Lecture Notes - Lecture 19: Natural Killer Cell, Molecular Recognition, Innate Immune System
11 Feb 2018
School
Department
Course
Professor
Document Summary
Non-specific mechanisms providing rapid initial response to a pathogen. Immune response is the same regardless of whether that pathogen has been encountered previously. Does(cid:374)"t (cid:272)ha(cid:374)ge (cid:449)ith e(cid:454)pe(cid:396)ie(cid:374)(cid:272)e/ su(cid:271)se(cid:395)ue(cid:374)t exposure first stop pathogens from entering body with barrier defenses e. g. skin, mucous membranes lining exchange surfaces toxin secretion second, deal with pathogen if it breaches barrier defences and enters body. Animals must be able to differentiate pathogens (cid:894)(cid:862)(cid:374)o(cid:374)-self(cid:863)(cid:895) from their own cells (cid:894)(cid:862)self(cid:863)(cid:895) Molecular recognition: specific receptors detect a small number of highly conserved molecules present in many different pathogens called a toll or toll-like receptor. Recognition leads to range of responses to deal with pathogen encapsulation and phagocytosis expression of antimicrobial proteins local inflammation or fever (systemic inflammation) Immune cells use only a few receptors to detect specific, highly conserved, chemicals in fungi, bacteria and virus that do not occur in animals cells in mammals, different tlrs recognise different pathogen molecules.
