Week 3 - Inflammation, Phagocytosis, Innate Immunity Flashcards
True or False: The skin is the largest immune defence organ as it provides a physical barrier to invaders?
True
What do oil glands of the skin secrete? And is this molecule harmful to all pathogens?
Oil glands secrete peptides. No, these peptides can keep down bad bacteria but help/leave alone bacteria that defend you from other bacteria.
What enzymes reside in the mucus of the lungs and gut? What is their function?
Lysozomes. They chew up the coats of bacteria.
What defence mechanisms does the stomach have?
Mucus = lysozymes and acid.
What can be the downside of decreasing the inflammatory response?
Increase in recovery time.
What is the purpose of a fever?
It sequesters iron from the blood making it harder for bacteria to grow.
What are the 3 processes that occur when skin is penetrated?
Cytokine release (to broken skin and bacteria)–>neutrophils–>chemokine release (type of cytokine to attract more cells to site)
Describe the steps of migration of a neutrophil across the endothelium.
Binding of Lectin to Mucin increases cell ‘stickiness’, eventually leading to arrest and then migration.
What are the 2 ways in which Toll-Like Receptors can be oriented?
Plasma = receptor on the outside of the plasma membrane and signaller inside. Endosome = receptor on the inside and signal outside.
Why are viruses not recognised by the innate immune system by their membrane patterns?
Because these are borrowed from other cells. And so not recognised by the pattern system of the II.
What are viruses recognised by?
Nucleic Acid
What 2 features distinguish bacterial cells from our cells?
- Bacteria flagella have methylated patterns in their flagella DNA
- Different cell wall compounds
What makes yeast different from your cells?
Cell wall compounds
What unicellular eukaryotes are hard to detect and why?
Giardia and Trypanosome, flagella the same as ours.
Why are tapeworms hard to detect?
Multicellular eukaryote
What do Pattern Recognition Receptors do?
They detect patterns that can’t change very significantly in pathogens without changing function = non-functional.
Name 2 patterns that are readily recognised?
Flaggelin and profilin
Name at least 2 targets of TLR.
Carbohydrates, Chitin, Peptidoglycans, Lipopolysaccharide, Nucleic Acid
List 3 innate immune cells that phagocytose.
Macrophage, Neutrophil, Dendritic Cell.
What is formed within a phagocytosing WBC when a pathogen has been attacked?
The pathogen is put in a vacuole called a phagosome.
What binds with a phagosome inside a cell and what does it do?
A lysozome binds and it adds compounds for pathogen digestion.
What is an example of an enzyme complex that is activated in the phagolysozome wall and what process does it begin?
NADPH. Through respiration/oxidisation process it produces toxic compounds.
What are 3 reactive oxygen species?
superoxide radical, hydrogen peroxide and hydrochlorous acid.
What are 3 reactive nitrogen species?
nitric oxide, sulphur, peroxynitrous oxide.
