Immunology Flashcards
what are the innate immune defences in the eye
blink reflex, physical properties and limited) exposure (small size)
what is the blink reflexed used for
flushing things out of the eye
what immunological properties do tears contain
lysosomes, IgA and IgG
how does the mucous layer of the eye help protect it
its is anti-adhesive
what 7 chemical immunological properties are found on the eye surfaces
lysozymes, lactoferrin and transferrin, tear lipids, angiogenin, IgA, complement, IL6 and IL8
what are lysozymes affective against
gram -ive and fungi (destroy cell wall)
what are tear lipids affective against
antibacterial to cell membranes
what immune cells are present in the eyes themselves
neutrophils, macrophages and conjunctival mast cells
where is the only part of the eye with lymphatic drainage
conjunctiva
what are the main APCs for external eye
langerhans
what effector cells are present in the adaptive immune response of the eye
CD4+T, CD8+T and B cells
what type of lymphoid tissue is in the conjunctiva
mucosa associated lymphoid tissue (MALT)
describe the environment and cells present in the cornea and sclera (5)
avascular, tough collagen coat, no lymphoid, langerhans in periphery, down-regulated immune environment
what immunoglobulin is present in the lacrimal gland and conjunctiva
IgA
where is the blood ocular barrier
vitreous, choroid and retina
what is immune privilege and what are some sites in the body where it is active
tolerate antigens without inflam response - brain/ CNS/ testes/ placenta / EYES
what sites in the eye have immune privilege
cornea, ant chamber, lens, vitreous cavity, subretinal space
what is the anterior chamber associated immune deviation (ACAID)
active mechanisms that down-regulate immune response eg inhibition of type IV hypersensitivity and non-complement antibodies
name some autoimmune conditions of the eye (5)
uveoretinitis / dalen fuchs nodule / keratoconjunctivits sicca / retinal autoantibodies / sympathetic ophthalmia
what is sympathetic ophthalmia
rare, bilateral granulomatous uveitis from trauma/ surgery to ONE eye
what process causes sympathetic ophthalmia
secondary autoimmune to ocular antigens which illicits sympathetic response in uninjured eye
describe type 1 hypersensitivity and a condition it causes in the eye
immediate hypersensitivity - mast cells + B cells –> IgE - acute allergic conjunctivitis
describe type 2 hypersensitivity and a condition it causes in the eye
direct cell killing - antibody mediated and complement - ocular cicatricial pemphigoid
describe type 3 hypersensitivity and a condition it causes in the eye
immune complex mediated - autoimmune corneal melting
describe type 4 hypersensitivity and a condition it causes in the eye
T helper cells - interferons, interleukins, TNF etc - corneal graft rejection
