Induced Innate Immunity Flashcards
Quiz 3
What is the purpose of the macrophage Osteoclast
Bone resorption
What are the two main types of monocytes
-Classical (CD14+)
-Non-classical or patrolling (CD14+ CD16+)
Are Monocytes macrophages
yes
What are the two different macrophages the classical monocytes can become when activated
-M1-like pro-inflammatory phagocytotic
-M2-like anti-inflammatory, wound healing
What are the two main classes of Macrophages
-M1- cytotoxicity, inflammatory, tissue damage
-M2- immune suppression, anti-inflammatory, and tissue repair
What are the three cells that are granulocytes
Neutrophils, eosinophils and basophils
Where are granulocytes normally found
in the blood and diseased sites
which granulocyte has the highest phagocytic acitvity
neutrophils
What is the function of conventional/ classical dendritic cells (cDC or just DC)
phagocytosis and antigen presentation
What is the function of plasmacytoid dendritic cells (pDC)
produce many cytokines
what is the innate role of type I interferons
Anti-viral cytokines
What will most pathogens encounter first
macrophages
What are the roles of macrophages/ cCDs (four listed)
-recognize pathogen
-Destro pathogen
-signal for reinforcements
-present antigens
How do you distinguish host, commensal, and pathogens?
Pathogen-associated molecular patterns (PAMPS)
How do you distinguish good host cells from bad host cells?
Damage-associated molecular patterns (DAMPS)
What are PRRs
Pattern Recognition receptors, recognize PAMPs
What are two examples from the complementary system that are PRRs
MBL and ficolin
What are Phagocytic receptors
-receptors that upon binding, induce phagocytosis
-recognize a larger range of PAMPs
-also binds apoptotic cells
-They are also complement receptors (binds C3b)
What are toll-like receptors (TLRs)
-deletion of toll leads to chronic infection (found in fruit fly)
-all have distinct leucine-rich repeat structures (membrane-bound)
Describe the steps to the main pathway for bacterial sensing TLR’s
-poly-Ub binds TAK1 (serves as “scaffold”, brings close to IRAK1/4, TAK1 gets phosphorylated)
-P-Tak1 phosphorylates IKK
-IKK now phosphorylates IkB
How does IkB keep NFkB cytoplasmic
-NFkB is a transcription factor
-IkB blocks the NFkB nuclear localization signal (keeps it cytoplasmic/inactive)
-IkB is phosphorylated/degraded (NFkB is free to go nuclear)
How can TLR activate the anti-viral interferons
-Through IRF (Interferon response factor), activates transcription of type I interferon genes
-can work through poly-Ub
-or can directly phosphorylate a IRF
What protein can overcome the issue of TLRs only being able to sense PAMPs outside the cell when intracellular bacteria will release cell-wall pieces inside the cell
The NOD proteins
What are NOD proteins
-Nucleotide-binding Oligomerization Domain (NOD)
-cytoplasmic innate sensors (not membrane attached, has leucine-rich repeats too)
-contains a second domain (this determines the effect of activation)
Where is the CARD domain found
The CARD domain is on the end of the NOD protein
What is the function of the CARD domain
resides in the cytoplasm in an inactive form and recruits RIP2
What is the function of NOD with pyrin domain (NLRP)
-generates inflammatory signals
-creates inflammasome
-induces pyroptosis (inflammatory cell death)
What is RIG-1
-sense viral RNA
-ssRNA without a cap
What is MDA-5
-sense viral RNA (most viruses don’t have transcript with a 5’ cap)
-dsRNA (does not exist in host)
What is STING
-senses viruses AND bacteria through cyclic dinucleotides
List five characteristics of Lysosomes that make them useful for phagocytosis
-harsh
-low pH
-ROS/RNS (reactive oxygen/ nitrogen species)
-AMPs
-degrading enzymes
What two things merge to form phagolysosomes
phagosomes and lysosomes
What receptor stimulates ROS burst and chemotaxis
the fMet-Leu-Phe receptor
