Lecture #1 Flashcards
Name some phagocytes.
Macrophages (Tissue Residents)Neutrophils (Recruited from Blood)Dendritic Cells (Tissue Residents)
What types of immune cells do peptides turn on?
ab-T cells and B cells
What types of immune cells do glycoproteins/carbohydrates turn on?
B cells, Macrophages/Neutrophils/DCs/Tissue Cells
What types of immune cells do glycolipids and phospholipids turn on?
B cellsNKT cells, gd-T cells
What types of immune cells do peptidoglycans/nucleic acids/flagella turn on?
B cellsMac/Neu/DC/Tissue via TLRs
Name phagocyte cell surface receptors
Complement, Fc, MHC Class II, TLR
Name some chemotactic agents.
C5a, LTB4, Chemokines (IL-8, MIP, MCP)
Name some ways phagocytes can kill bacteria.
Metabolic BurstSuperoxide (via NADPH oxidase)H2O2 (via Superoxide Dismutase)Acid Hydrolases, Muramidase, Lysozyme, Defensins
Name the two types of receptors on a macrophage.
Phagocytic receptor and signaling receptor
Cytokines involved in inflammation?
Il-1, TNF-a, IL-6, CXCL8, IL-12
What does IL-1/TNF-a do?
Increase BV permeability
What does IL-6 do?
Increase fat/muscle metabolism –> Fever
What does CXCL8 do?
Recruits neutrophils
What does IL-12 do?
Recruits/Activates NKs, strengthen Mac response
What cytokine induces acute phase proteins? Where are they made? Name three.
IL-6LiverCRP, Fibrinogen, Mannose-binding Protein
What do acute phase proteins do?
Opsonization and Complement Activation
What is sepsis?
Systemic Inflammatory response due to Infection
What two parts does C3 split into? What do they do?
C3a – Recruits PhagocytesC3b – Tags bacterium for destruction
How does C3b affect bacterium after binding?
Binds macrophage CR1, causing endocytosisAfter endocytosis, eventually phagolysosome breaks up bac.
Receptors on Macrophages?
Complement receptor 3/4 (Mac-1)LPS Receptor (CD14)Toll Like Receptors
What are the components involved in LPS recognition?
CD14, TLR4, MD2, LPSX2 (its a dimer)
What does TLR 2/6 recognize? Where is it located?
Lipoteichoic Acid/Zymosin Plasma Membrane
What do TLR 4/4 homodimers recognize? Where are they located?
LPSPlasma Membrane
What does TLR9 recognize? Where is it located?
Unmethylated CpG-rich DNA
Describe the molecular steps of TLR activation.
TLR–>TIR Domain–>MyD88–>IRAK4–>TRAF6–>IKK–>Degradation of IkB –> NFkB transcribes cytokines
What receptor is unique to neutrophils?
N-formyl methionine receptor
What are competitors used in bacterial destruction?
Lactoferrin and B-12 binding protein
How do defensins work? What makes defensins?
electrically attracted to lipid bilayer, make pores. Made by paneth cells.
What are the steps of Leukocyte adhesion?
Rolling Adhesion, Tight Binding, Diapedesis, Migration
What molecule facilitates rolling adhesion?
Selectins
What molecule facilitates tight binding?
Chemokines (like CXCL8)
What molecule facilitates diapedesis?
Integrins (like ICAM-1)