Inflammation 2.1: Acute Pt. 1 Flashcards
What activates TLRs?
PAMPs
What does TLR activation cause?
upregulation of NF-kB
What does upregulation of NF-kB cause?
nuclear transcription of immune response genes –> more mediators produced
Where are TLRs found?
on cells of the innate immune system (macs, dendritic cells)
What is CD14?
a TLR found on Macs that recognizes LPS on gram (-) bacteria
Where is LPS found?
on the outer membrane of gram (-) bacteria
What inhibits NF-kB?
glucocorticoids
Where does arachidonic acid come from?
the phospholipid cell membrane by phospholipase A
What is the key derivative of the COX pathway?
prostaglandin
What do prostaglandins mediate?
vasodilation of arterioles, increased vascular permeability of the post capillary venule, and pain
PGE2 mediates ____.
fever (fEEEEEEEEver)
What does LTB4 (leukotriene B3) do?
it attracts and activates neutrophils
Name 4 key mediators of neutrophil activation and attraction.
LTB4, C5A, IL-8, and bacterial products
What do the leukotrienes do?
mediate vasoconstriction of arterioles, bronchospasm, and increased vascular permeability (smooth muscle contraction)
From what do leukotrienes come from?
5-lipooxygenase
Where are mast cells found?
in CT
Name 3 ways that mast cells can become activated.
tissue trauma, complement proteins C3a and C5a, and cross-linking of cell-surface IgE by antigen
What do macs produce in their delayed response?
arachidonic acid, leukotrienes
Name 3 ways complement can be activated.
- classical (C1 binds to IgG or IgM bound to antigen)
- alternative pathway (microbial products)
- MBL (mannose binding lectin)
What happens in the classical pathway of complement pathway?
GM makes Classic cars
IgG or IgM activates it
What happens in the alternative pathway of complement pathway?
microbial products activate it
What happens in the MBL pathway of complement pathway?
MBL + mannose on microorganisms activates it
All complement pathways lead to?
C3 convertase generation –> C3a and C3b –> C5 convertase formed –> C5a and C5b –> C6-C9 form MAC –> lysis of microorganism
What do C3a and C5a do?
trigger mast cell degranulation
What does C5a do?
it’s a neutrophil chemotactic
What does C5b do?
it’s an opsonin for phagocytosis
What does the MAC do?
lyses microbes by creating holes in the cell membrane
What is Hageman factor?
a proinflammatory protein found in liver
What does activated Hageman factor cause?
DIC in severe gram (-) sepsis
coag and fibrinolytic systems, complement
What activates Hageman factor?
subendothelial or tissue collagen
What does the kinin system do?
cleaves HMWK to bradykinin –> vasodilation, increased vascular permeability, and pain
What are the 2 things that mediate pain in acute inflammation?
PGE2, bradykinin
