Week 1 - Immunology Flashcards
does lysozyme destroy Gram - or + bacteria (and fungi?)
gram negative
does lactoferrin + transferrin destroy gram + or - bacteria?
gram positive
what are Langerhans cells?
dendritic cells
lots of them at the peripheral cornea
what is the cornea
the transparent cover of the iris + pupil + anterior chamber
what is the sclera
the “white” - fibrous + opaque collagen outer layer
what are the two types of conjunctiva and where are they?
bulbar = clear, covers eyeball
palpebral = lines inner eyelid
what has better immune protection - the conjunctiva or cornea+sclera ?
the conjunctiva - has drainage, APCs, T cells and IgA
the cornea+sclera have a tough collagen coat for protection but not much else. Langerhans cells in peripheral cornea.
does the lacrimal gland have good immune protection?
yes - MALT (mucosa ass. lymphoid tissue)
lymphoid = B and T cells
also lots of IgA and T cells
do the deep structures - vitreous + choroid + retina have good immune protection?
not really
lack APCs
what is ocular Immune privilege?
in what surgery is it v. helpful?
the eye is able to tolerate antigens WITHOUT them causing inflammation- its has a separate “local” immunity
beneficial in corneal transplants?
what factors allow ocular immune priveledge?
blood-tissue barrier immunosuppressant molecules (ACAID)
No direct lymphatic drainage
2 “cons” of ocular immune privelegde?
- malignancy
2. Sympathetic ophthalmia
what is sympathetic ophthalmia?
autoimmune attack on “self antigens” normally processed “locally” that get into the systemic immune response
unilateral damage –> bilateral uveitis
when does sympathetic ophthalmia occur?
either due to (unilateral )trauma or surgery
what is type 2 hypersensitivity ?
antibody mediated cytotoxicity
what is type 4 hypersensitivity ?
immune complex mediated
what type of hypersensitivity is Ocular cicatrical pemphigoid?
type 2
give an example for all types of hypersensitivy in the eye
1 - allergic conjuncitivity (+ chemosis)
2 - cicatrical pemphigoid
3 - autoimmune corneal melting
4. corneal graft rejection
what can overuse of ocular steroids lead to ? (2)
cataracts + glaucoma
