Lecture 7 Flashcards
What are cytokines?
Low molecular weight proteins produced during inflammation to act as chemical attractants
What is tumour necrosis factor?
Cytokine which up regulates inflammation
What is cachexia?
Wasting
Why does tumour necrosis factor have limited uses against tumours?
Not effective against the most common tumour types ad induces unpleasant flu like symptoms
What are the 3 effects of TNF and interleukin1 at low concentrations?
Vasodilation
vasopermeability
expression of adhesion molecules on endothelial cells
What are the 4 effects of tumour necrosis factor and interleukin1 at high concentrations?
Fever, Coagulation cascade, fibrosis, cachexia
What is the role of neutrophils?
To be rapidly proliferated and to be the initial non specific defence against invaders
What is sterile inflammation?
Injury without infection
What is the function of eosinophils?
Anti-parasitic but can cause allergies
What are the functions of basophils?
Regulation of inflammation but can cause allergies
Give 5 examples of DAMPs
ECM fragments intracellular proteins, DNA and RNA ATP Crystals
What DAMPs do toll-like receptors bind?
ECM fragments,
intracellular proteins,
DNA and RNA
What binds to RAGE receptors?
intracellular protiens
What binds to P2X7 purinergic
ATP
What receptor binds crystals?
Components of inflammasomes
What does signalling from TLRs and P2X7Rs do?
Activation of inflammasomes resulting in the release of IL-1alpha when cells undergo lysis causing endothelial cells to become adhesive for leukocytes
What is margination
When endothelial cells become adhesive for neutrophils
What is the role of P and E selectins?
To allow for leukocytes to loosely contact the vessel wall rolling along its surface
What causes adhesion flattening of neutrophils?
Upregulation of Intracellular adhesion molecule-1 and vascular adhesion molecule 1 as well as leukocyte function associated antigen 1 on neutrophils
What is transmigration?
Movement of leukocytes through the endothelial cells with use of enzymes to remove the basement membrane
What are the chemotatic signals that release leukocytes?
Proteins from broken cells like N-Formylated peptides
Chemokines
Leukotriene B4, Complement Products C3a, C5a
Bacterial Products
What are the three processes that phagocytes use to kill microbes?
Phagocytosis, degranulation and respiratory burst
What is the process involved in producing a respiratory burst?
NADPH oxidase reduces oxygen to superoxide, this results in rapid entry of K+ counter ion, The super oxides is reduced to hydrogen peroxide by super oxide dismutase, which then reacts with Myeloperoxidase to form hypochlorous acid which kills the pathogen
What is suppuration?
Liquefactive necrosis
