Immunology

Question 1

Name the three components of the innate immune system of the eye

Answer 1

• Blink reflex (physical)
• Tears (chemical)
• Neutrophils, macrophages, mast cells (cellular)

Question 2

What is present in tears that help protect against unwanted material

Answer 2

Anti-microbial agents e.g. lysozymes, lactoferrin, transferrin and IgA

Question 3

What is the only part of the eye that has lymphatic drainage

Answer 3

The conjunctiva

Question 4

What is meant by ‘immune privilege’

Answer 4

Certain sites of the human body have immune privilege; they are able to tolerate the introduction of antigens without eliciting an inflammatory response

Question 5

What areas of the body are immune privileged

Answer 5

brain/CNS (controversial),
testes,
placenta/foetus,
cartilage,
eyes

Question 6

What areas of the eye are immune privileged

Answer 6

• Cornea
• Anterior chamber
• Lens
• Vitreous cavity
• Subretinal space

Question 7

What are the mechanisms for ocular immune privilege

Answer 7

• blood ocular barrier
• lack of direct lymphatic drainage
• anterior chamber-associated immune deviation
  
  • rich in immunosuppressive molecules
  • anterior chamber is avascular
  • cells ONLY in PERIPHERAL cornea

Question 8

Describe the immune system of the cornea & sclera

Answer 8

Is immune privileged…
- no lymphatics
- vascular
- immunosuppressants

Limited protection by….
- tough collagen coat
- langerhans cells in PERIPHERAL cornea

Question 9

Describe the immune system of the conjunctiva

Question 10

Describe the immune system of the vitreous/choroid/retina

Question 11

What are the role of the lacrimal gland & system in eye immunity

Question 12

Give an example of a type I hypersensitivity in the eye

Question 13

Give an example of a type II hypersensitivity in the eye

Question 14

Give an example of a type III hypersensitivity in the eye

Question 15

Give an example of a type IV hypersensitivity in the eye