Flashcards in Dendritic Cells Deck (55)
What is the general function of NOD-like receptors?
intracellular sensors of bacterial infection and cellular damage
What is the general function of RIG-I-like receptors?
detect cytoplasmic viral RNAs
What pathway fo RIG-I-like receptors trigger?
What is the function of activating MAVS pathway?
induce type 1 interferons and pro-inflammatory cytokine production
What is the special function of dendritic cells?
only true professional APC with ability to activate naive T cells
What cells are considered professional APCs?
B cells; macrophages and dendritic cells
What are hte features of dendritic cell biology which make it suited for initiating immune responses?
efficient at antigen presentation; accumulate within T cell areas of lymphoid organs and ability to polarise T cells
What is the dramatic structual reorganisation of dendritic cell maturation known as?
What are the features of immature dendritic cells?
peripheral and lymphoid tissues; highly endocytic; low surface MHC-II and costimulators
What is the main function of immature DCs?
What is the main function of mature DCs?
T cell stimulation
What are the features of mature DCs?
foudn in lymphoid tissues; endocytosis reduced; high surface MHC-II and costimulators
What do DCs process antigens into for presentation?
Where do DCs mature?
secondary lymphoid organs
What causes DCs to mature?
pathogen derived danger signals ; pathogen derived TLR ligands
What changes in the function of the DC in maturation?
peptide loading; half-life and delivery of MHC molecules is increased; costimulatory molecules increases
What is the proteolytic apparatus in the endosomal-lysosomal system?
cathepsins and other lysosomal hydrolases
what is the proteolytic system in the cytosol?
What causes MHC class II molecules to be actively diverted to lysosmes in immature state?
What is ubiquitination?
proces of attachment of one or many subunits of ubiquitin to a target protein
What is the function of ubiquitin?
functions as a protein interaction module or to target protein for degradation by the proteasome
What happens initially to endocytosis in a maturing DC?
upregulated- increase chance of capturing pathogen
What chemokine receptor is upregulated in maturing DCs?
What receptors are involved in activating DC maturation?
toll-like receptors; cytokine receptors; TNF-receptor family; FcR; sensors for cell death
What do plasmacytoid DCs produce in response to viral stimuli?
What is the function of receptor-mediated endocytosis?
allows uptake of macromolecules through specialised regions of hte plasm membrane-coated pits
What is found on the outside of endocytic vesicles used in receptor-mediated endocytosis?
What is the binding of ligands to C-type lectins dependent on?
What is a Langerhan cell?
dendritic cell in the skin