Immunology & Pharmacology

Question 1

T/F: Tears contain a mucus layer

Answer 1

True - anti-adhesive function

Question 2

Lysozyme is effective against what type of pathogen?

Answer 2

Gram negative bacteria & fungi

Question 3

Lactoferrin & transferrin in tears is active against which pathogen type?

Answer 3

Gram positive bacteria

Question 4

Which cytokines are responsible for recruitment of leukocytes in the eye?

Answer 4

IL-6, IL-8 and MIP

Question 5

What innate immune cells are present in the eye (3)

Answer 5

1) Neutrophils
2) Macrophages
3) Mast cells

Question 6

What is the principle APC for the external eye?

Answer 6

Langerhans cell

Question 7

Which type of MHC is expressed on APCs?

Answer 7

MHC II

Question 8

Where are Langerhans cells concentrated at on the extenral eye?

Answer 8

Limbus (corneal-scleral junction)

Question 9

Where are Langerhans cells absent from on the external eye?

Answer 9

Central 1/3rd of cornea

Question 10

What is the only part of the eye with lymphatic drainage?

Answer 10

Conjunctiva

Question 11

The eye has MALT. T/F?

Answer 11

True

Question 12

T/F: The eye has no commensal flora.

Answer 12

False

Question 13

Where does the “down-regulated” environment of the eye begin?

Answer 13

Cornea & sclera (fibrous layer)

Question 14

Lacrimal gland secretions contain which antibody?

Answer 14

IgA

Question 15

Why is the inner eye considered “a petri dish with a lid”

Answer 15

There are relatively few defences within the eye. The lid is the conjunctiva which has lymphatic drainage and more immune surveillance.

Question 16

Describe ACAID

Answer 16

The placement of a foreign antibody into the eye can result in systemic tolerance to that antigen (due to active down-regulation of immunity)

Question 17

What role does ACAID serve

Answer 17

Protects the eye and visual axis from collateral damage of an immune response by suppressing future responses

Question 18

What are the 3 main ways the eye establishes immune privilege

Answer 18

1) Separation (normal cornea lacks blood and lymphatic vessels, corneal cells also have reduced MHC1 and NO MHC2)
2) Inhibition (local factors inhibit response)
3) Regulation (peripheral tolerance to antigens as in ACAID)

Question 19

What does ACAID stand for

Answer 19

Anterior Chamber Associated Immune Deviation

Question 20

Typical features of sympathetic ophthalmia (2)

Answer 20

1) Bilateral

2) Granulomatous uveitis

Question 21

What is sympathetic ophthalmia occur secondary to?

Answer 21

Autoimmune reaction to ocular antigens

Question 22

What’s the first T-cell to infiltrate the eye in sympathetic ophthalmia?

Answer 22

CD4+

Question 23

What cell-type mediates sympathetic ophthalmia?

Answer 23

T-cell

Question 24

The injured eye in sympathetic ophthalmia is known as the..

Answer 24

Exciting eye

Question 25

The fellow eye in sympathetic ophthalmia is known as the..

Answer 25

Sympathising eye

Question 26

T/F: Allergy occurs upon first exposure to an allergen.

Answer 26

False - needs a priming event.

Question 27

What is chemosis?

Answer 27

Oedema of the conjunctiva

Question 28

Ocular pemphigoid is what type of immune reaction?

Answer 28

II

Question 29

Type II hypersensitivity reactions do damage how?

Answer 29

Direct cytotoxicity

Question 30

Corneal melting (autoimmune) is due to what type of H/S?

Answer 30

Type III (immune complex)

Question 31

Corneal graft rejection is what type of H/S?

Answer 31

Type IV

Question 32

What are the ocular side effects of steroids?

Answer 32

Cataracts, glaucoma

Question 33

The epithelium tends to let what type of drugs penetrate?

Answer 33

Lipophilic/ hydrophobic (lipid soluble drugs)

Question 34

The stroma tends to let what kind of drugs penetrate?

Answer 34

Lipophobic/ hydrophilic (water-soluble drugs)

Question 35

Hydrophilic drugs will be limited by what eye layer

Answer 35

Epithelium

Question 36

Hydrophobic drugs will be limited by what eye layer

Answer 36

Stroma

Question 37

For topical steroids, adding an alcohol or acetate group has what effect on that steroid?

Answer 37

Makes it more hydrophobic

Question 38

For topical steroids, adding a phosphate group has what effect on that steroid?

Answer 38

Makes it more hydrophilic

Question 39

What drug will penetrate better in the inflammed cornea: prednisolone acetate or prednisolone phosphate?

Answer 39

``` Prednisolone acetate (nb: this does not mean phosphate is useless - this can be useful for when a low-dose of steroid is wanted) ```

Question 40

What drug addiction can be used to enhance corneal penetration?

Answer 40

Benzalkonium

Question 41

What is bimatoprost used for?

Answer 41

Lowering IOP in glaucoma

Question 42

How can systemic absorption of topical eye steroids be reduced?

Answer 42

Punctal occlusion (with fingers for 5 minutes)

Question 43

A sub-tenon administration places a drug where?

Answer 43

Behind orbital space

Question 44

An intracameral administration places a drug where?

Answer 44

Anterior chamber (cornea)

Question 45

Which drug is useful post-operatively for cataract surgery?

Answer 45

Steroid

Question 46

List some treatments for glaucoma (3)

Answer 46

1) Prostanoids (e.g. Latanoprost) 2) Beta-blockers 3) Carbonic anhydrase inhibitors (e.g. Dorzolamide)

Question 47

Which drug is often administered intra-vitreal?

Answer 47

Anti-VEGF. | Also used for antibiotics in endopthalmitis.

Question 48

Phenylephrine will have what effect on the eye?

Answer 48

Dilating the pupil (sympathomimetic)

Question 49

Tropicamide has what effect on the eye?

Answer 49

Mydriatic (block parasympathetic supply to iris - unopposed sympathetic activity)

Question 50

Ethambutol causes what important eye side effect

Answer 50

Optic neuropathy

Question 51

Chloroquines cause what important eye side-effect

Answer 51

Maculopathy