Innate immunity fernando overview Flashcards
(36 cards)
What cells infiltrate and are importnat for wound healing in the skin?
neutrohphils and macrophages
What kind of 3 categories of innate immunity are there?
physical (barriers), chemical and cellular
What sorts of preformed components are important immediate innate response?
complement, collectins and ficolins, mucus, nautral Ig. AND PENTRAXINS.
What innate immunity is seen in the early induced response?
Recognition of PAMPs and cellular rsponses, DC migration etc.
What are the 3 external defences of innate immune system?
barrier (skin+ tight junctions) mucous membranes, secretions (can include IgA and lysozymes, acidic secretions, AMP).
4 broad INternal defences?
AMPs, phagocytes, NK cells and inflammatory responses.
what mechaical and fluidmovement in skin, GI tract? Respiratory? urogenital and eyes?
Skin you have sweating and sloughing off of skin.
GI, you have movement of fluid and mucus food and saliva.
Respiratory, fluidand mucus movement by primary cilaia.
Urogential tract, flow of fluid, mucus, sperm and urin.
Eyes, flow of tears?
Secretions in skin, GI tract? Respiratory? urogenital and eyes?
Sebum secretions in the skin can contacain lactic acid and lysozyme.
Gi tract secretions, acid and proteases.
Respiratory tract, lysozoymes in nasal secretions.
urogential tract secretions, acidity in vagina, spermine (zinc in semen)
eyes, lycsosomal sectretion in tears.
what additional defences of barriers?
the microflora and AMPs.
What three kinds of junctions do you have at epithelial surfaces?
tight junctinos (occludins and claudins), desmosomes and gap junctions and (adherens?).
what kind of molecules do desmosomes use for attachments and what cytoskeletal component are they attached to?
desmogleins and desmocollins. Attached to intermediate filaments.
Molecules involved in tight junctions
occludins and claudins attached via adaptors to actin cytoskeleton.
What cytokine can alter the permeability of gap junctions? What kinase does it activate, and what cytokines antagonise this?
TNF-a activates MLCK (kinase) which increases the permeability of epithelium, and IL-10 and TGF-B prevent this.
What symptoms associated with occludin and claudin mutations?
Mostly perinatal death. May get barrier defects like itchyosis and scherolising cholangitis. Or CNS myeloid and schwann cell defects.
What 2 chemical barriers are particularly important?
lactoferrin and lysoszymes, they have synergistic effects onE.coli killing.
What do lysozymes cleave?
Cleave peptidoglycan of bacterial cell walls.
What other iron sequestering molecules are there?
lactoferrin, ferritin and hepcidin (liver).
what kind of glycosylation events for mucins?
N and O glycostylation, prevents proteolysis and degradation by glucases.
Why have different mucins?
To select for and deal with different bacteria.
Generally two different types of mucins?
membrane-associated mucins (e.g. Muc1,3 and 4)
Secreted mucins, e.g. Muc2 and Muc5ac.
where are the secretory mucins 2 and 5ac important?
muc2 is important in the small intestine and colon, and Muc5ac important in the stomach.
What are three general models of AM peptide actions?
pore formation, thinning of memrbanes (targeting specific phospholipids), and influencing membrane polarisation.
What are 2 particularly important AMPs for neutrophils? and what kind of structure?
cathelicidin has an a helix, and B human defensin in neutrohpils has a a helix and B pleated sheet that inserts into the membrane.
what are AM proteases? Where are they important/ cells produced
lysozymes, are found in the intestine, tears, and saliva nasal sections.
Also found in the sebum of the skin.
