Lec. 11 Immunity Flashcards
How can an organ like the human gut that is only a ~20 feet long have a surface the size of a tennis court?
The fold and villi massively increase the surface area.
What is horror autotoxicus?
The horror of having one’s own immune system unleashed against oneself.
What is autophagy? (ah-ta-fuh-gee)
In my own words: Process where cells can eat structures within the cell by sequestering them inside an autophogosome and digesting them.
What is mucus?
A biogel, of highly hydrated mix of water and glycoproteins secreted (produced) by cells
What is the first line of defense of your gut from foreign invaders?
The Mucus layer.
What is the origin of most immune cells?
The bone marrow
What kind of information does the immune system process?
Molecular information about self and non-self, consisting of composition and shape of molecules and the patterns they form.
How can the cells lining the gut detect microbes that can form a threat of infection?
By expressing innate receptors that specifically detect bacterial molecular patterns.
What is the complement system?
A part of the innate immune systems that relies on numerous secreted proteins that can distinguish self from non-self
and form a powerful membrane attack system as well as amplify the effect of antibodies and other molecular beacons that recognize non-self or “altered self”.
Do soluble innate immune proteins in the blood tag for destruction or tag for
Protection?
Both.
What happens to B-cell that make antibodies specific for self molecules?
They are forced to undergo suicide.
How can the same gene give rise to different proteins?
Alternative splicing,
or different post-translational modifications, or somatic recombination.
What is the difference between an antigen and an antibody?
Antigens are molecules that can be recognized by the immune system, antibodies are molecular probes that recognize antigens.
Mention a key difference between innate and adaptive immunity.
Innate immunity acts rapidly, adaptive immunity can learn to detect new patterns and form memories.
What do the acronyms PAMP, DAMP and SAMP refer to in the context of immunity?
Pathogen-associated, Damage-associated and Self-associated molecular patterns.
What is the difference between HLA and MHC?
They are the same, HLA is also the other name for human MHC.
How can the immune system detect the presence of a virus that has already infected a cell?
The HLA molecules of the cell will present cellular content on the outside of the cell allowing the immune system to detect viral debris, intra-cellular parasites or cancer.
What is the name of the gut immune tissue”
GALT.
What are the lymphoid organs around the gut called?
Peyer’s patches.
What are mesenteric lymph nodes?
the tissue connecting the gut to the rest of the body.
What do the life threatening consequences of gut puncture wounds highlight about the gut microbiome?
That the gut bacteria are extremely dangerous if they invade our bodies.
Give two examples of external influence on gut immunity.
Breast feeding, nutrition, history of infection, antibiotics treatments.
What is Anaphylaxis?
A potentially life threatening, all-out immune response.
Do most people in the USA who avoid gluten have antibodies against gluten?
No, only a minority does.
