Inflammation Mediators Flashcards
(41 cards)
Toll-Like Receptors
Activated by PAMPs; upregulated NF-kB leading to activation of immune response genes to multiple immune mediators (also seen on lymphocytes for both acute and chronic)
PGI2, PGD2, PGE2
Vasodilation and increased vascular permeability; PGE2 also mediates pain and fever
LTB4
Attracts and activates neutrophils
LTC4, LTD4, LTE4
Vasoconstriction, broncospasm, and increased vascular permeability (by contracting smooth muscle)
Mast Cells
Activated by tissue trauma, C3a, C5a or cross-linking of cell surface IgE by antigen; release of histamine granules (vasodilation and increased vascular permeability)
What are Rubor (redness) and Calor (warmth) due to?
Due to vasodilation, resulting in increased blood flow; mediated by histamine, bradykinin, and prostaglandin
What is Tumor (swelling) due to?
Leakage of fluid from post-capillary venules into interstitial space (exudate); mediated by histamine (endothelial cell contraction) and tissue damage (endothelial cell disruption)
What is Dolor (pain) mediated by?
Bradykinin and PGE2 that sensitive free nerve endings
What is Fever mediated by?
Pyrogens (such as LPS) from bacteria that cause macrophages to release IL-1 and TNF, increases COX in perivascular cells of the hypothalamus
What mediator raises set point temperature?
PGE2
What causes margination?
Vasodilation, slowing down flow in POST-CAP VENULE; allowing cells to marginate from center to periphery
What releases and mediates P-selectin?
Released from: Weibel-Palade bodies
Mediated by: histamine
What induces E-selectin?
TNF & IL-1
How does rolling occur?
Selectins bind to Sialyl-Lewis X found on leukocytes
Where and how are I-CAM and V-CAM regulated?
Upregulated on endothelium by TNF and IL-1
What do I-CAM and V-CAM interact with, what does it cause, and how does it happen?
I-CAM and V-CAM interact with Integrins on leukocytes; via C5a and LTB4 causing firm adheshion
What is LAD due to, and what type of disease is it? (x-linked, autosomal dominant, autosomal recessive)
Autosomal recessive defect of Integrins (CD 18)
How does LAD present?
First is delayed separation of umbilical cord, will see increased circulation of neutrophils, and recurrent bacterial infections that lack bus
What are neutrophils attracted by?
IL-8, C5a, LTB4
What do IgG and C3b do?
Phagocytosis; consumption of pathogens or necrotic tissue
What is Chediak-Higashi due to, and what type of disease is it? (x-linked, autosomal dominant, autosomal recessive)
Autosomal recessive defect in protein trafficking leading to impaired phagolysosome formation
How does Chediak-Higashi present?
Increased risk for pyogenic infections, neutropenia, giant granules in leukocytes, albinism, peripheral neuropathy
Fill in the enzymes on top of the arrows:
O2 —> O2* —> H2O2 —> HOCl (bleach)
- NADPH oxidase (oxidative burst)
- Superoxide dismutase
- Myeloperoxidase
What is CGD due to, and what type of disease is it?
NADPH Oxidase deficiency leading to poor O2-dependent killing; x-linked recessive
