University:
York University
Course:
SC/BIOL 3120 | Immunobiology
Academic year:

2023
Views:

460

Pages:

3
Author:

Niklas

Innate Immune Receptors: PRRs bind withs PAMPs or DAMPs Cellular expression of PRRs: - all myeloid cells - Subsets of 3 types of lymphoid cells - non-immune cells that might come in contact with pathogens example epithelial and mucosal tittat expression within cells: - cell surface - Cytoplasm - endosomes why is it pugh Ticant that PAR expression is so we tyred? each PRR (and their subtypes) recognize various broad classes of pathogen patterns PRA Terriers the setten and stimulates a stapense that effectin Er semering the virus. Toll-Like Receptors (TLRs): - Transmembrane proteins - found on both the cell surface and endosomes - Broad range of specificities; can recognize and respond to several different PAMP/DAMP LOCATION MATTERS - Bacteria on outside - inflammatory response - Virases on inside - antiviral response Table 3-2 Pattern recognition receptors Pattern recognition receptor families Family Members Subcellular location Ligands Toll-like receptors (TLRs) TLR1, TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, TLR10, TLR11, TLR12, TLR13 Cell surface, endosomes Bacterial cell wall components, viral nucleic acids, bacterial flagellin, lipoproteins Retinoic acid-inducible gene (RIG)-I-like receptors (RLRs) RIG-I, MDA5, LGP2 Cytoplasm Viral RNA NOD-like receptors (NLRs) NOD1, NOD2, NLRP1, NLRP3, NLRC4, NAIP Cytoplasm Bacterial cell wall components, intracellular pathogens, damage-associated molecular patterns (DAMPs) C-type lectin receptors (CLRs) Dectin-1, Dectin-2, Mannose receptor, DC-SIGN, Mincle Cell surface Fungal cell wall components, bacterial cell wall components, viruses C-Type Lectin Receptors (CLRs): - membrane bound - 15 different types - recognize the carbohydrate components of various pathogens (and allergens) CLRs - Transmembrane proteins - found at the plasma membrane - Recognizes glycans (carbohydrates) from fungus and bacterial cell walls in a Ca++-dependent manner RIG-I-like Receptors (RLRs): RLRs - RNA helicase - Recognizes double stranded RNA - Cytoplasmic sensors of viral RNA - Trigger signaling pathways that activate: - NF-kB - IRFs (interferon receptor factors) NOD-like Receptors (NLRs): - Cytoplasmic proteins - Recognizes and responds to bacterial, viral, fungal, and parasitic PAMPs - Initiates autophagy by forming autophagosomes that fuse with lysosomes to kill bacteria - Can assemble into large complexes (inflammasomes) - Form inflammasomes Extracellular Space Cytoplasm