BIOL 435 Ch. 3 Part Three (Recognition and Response) Flashcards
PRRs
- pattern recognition receptors
- immune An receptor molecules
- recognize PAMPs
PAMPs
- pathogen associated molecular patterns
- represent motifs of recurring patterns on bacteria, yeast and parasites
receptors for PAMPs
- may uniformly recognize large numbers of bacteria that share the same PAMPs
- not clonally distributed, but are expressed equally on the same cell types
- may be integral membrane proteins or intracellular proteins
PRR families
- Toll-like receptor
- C-type lectin receptor
- Retinoic acid inducible gene-1 like receptor
- Nucleotides oligoermizatlon domain like receptor
- Absent-in-melanoma-like receptor
toll-like receptor (TLR)
- plasma membrane, endosomes, or lysosomes
- production of antimicrobials, antivirals and cytokines
- inflammation
- various ligands (microbial CHO, bacterial flagellin, viral RNA)
C-type lectin receptor (CLR)
- plasma membrane
- bind to CHO components of various things
- phagocytosis
- production of antimicrobials and cytokines
- inflammation
cytokine signal
- usually generate by the binding of a ligand to a complementary cell-bound receptor
- any event where a chemical messenger binds to a receptor with the result that the cell is instructed to change its metabolic or proliferative state
cytokine-receptor binding
-non-covalent
>may be of generally high affinity
cytokine-signalling end results
-often induce a change in the transcriptional program of the target cell
cytokines
-proteins that mediate the effector functions of the immune system
-can act in several ways:
>endocrine action
>paracrine action
>autocrine action
endocrine action
- released into the blood stream to effect distant cells
- sometimes
paracrine action
- released to effect nearby cells
- very common
autocrine action
- released, but then bind to receptors on the cell that produced them
- less common
- very important way for immune cells to be activated or be more activated
general properties of cytokines and chemokines
- pleiotrophic activity
- redundant activity
- synergy effect
- antagonist effect
- cascade effect
- combination of molecules will determine what will occur
pleiotrophic activity
-induces different biological effect dependent on target cell
redundant activity
-mediates similar effects on target cell