Ocular Immunity and Inflammation

Question 1

Is lactoferrin a component of innate or acquired immunity?

Describe it’s antimicrobial actions.

Answer 1

• Component of Innate Defense (Chemical Barrier)
• Antimicrobial protein in tears
• Sequesters essential iron and enhances lysozyme
• Tears prevent drying, dilute/remove microbes

Question 2

Is lysozyme a component of innate or acquired immunity?

Describe it’s antimicrobial actions.

Answer 2

• Component of Innate Defense (Chemical Barrier)
• Antimicrobial protein in tears
• Digests peptidoglycan (bacterial cell wall)
• Tears prevent drying, dilute/remove microbes

Question 3

Is mucins a component of innate or acquired immunity?

Describe it’s antimicrobial actions.

Answer 3

• Component of Innate Defense (Chemical Barrier)

- Glycoproteins that inhibit microbe attachment

Question 4

Is meibum a component of innate or acquired immunity?

Describe it’s antimicrobial actions.

Answer 4

• Component of Innate Defense (Chemical Barrier)
• Meibomian glands lipids that prevent evaporation of tear film, prevents tear spillage, and makes closed eyelids airtight
• *Helps tears wash away microbes**

Question 5

Is IgA a component of innate or acquired immunity?

Describe it’s antimicrobial actions.

Answer 5

• Innate Defense (chemical barrier)
• Found in all body secretions (Component of tears)
• Binds pathogens very well
• Does NOT activate complement…so it tends NOT to trigger inflammation

Question 6

Explain why Anterior-Chamber-Associated Immune Deviation (ACAID) is described as “active” immune privilege

Answer 6

• Active because antigen is injected into the anterior chamber and suppresses immune response
• Injected antigen is captured by APC’s
• APC’s migrate to spleen
• Regulatory T-cells (Tregs) induce peripheral tolerance and prevent classic Th1 (cell mediated) Type 4 Hypersensitivity

Question 7

Define uveitis.
What are its potential complications?
Symptoms?

Answer 7

• Inflammation within the eye (uvea is vascular layer)
• Complications: glaucoma, cataracts, neovascularization, blindness
• Symptoms: changes in vision, sensitivity to light, dark/floating spots, eye pain or redness

Question 8

What form of uveitis a is a patient with multiple sclerosis is most likely to develop?

Answer 8

Intermediate Uveitis - in vitreous chamber

Question 9

What type of hypersensitivity is prevented by ACAID?

Answer 9

Type 4 (cell-mediated)

Question 10

What is the most common form of uveitis?

Answer 10

Anterior Uveitis

Question 11

What is the least common form of uveitis?

Answer 11

Posterior Uveitis - in retina and choroid

Question 12

What is Pan-Uveitis?

Answer 12

Uveitis that involves the whole eye

Question 13

How is uveitis treated?

Answer 13

• Corticosteroids
• Immunosuppressive agents
• Biologics (monoclonal antibodies) such as Adalimumab

Question 14

Recall the source and action of defensins.

Are these innate or acquired?

Answer 14

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