Immune Complex Disease Overview

Type III Immune Complex Disease

• Immune complexes depositing in capillaries or joints leads to inflammation and tissue damage.
• If neutrophils and macrophages cannot phagocytize the immune complexes, they accumulate and exacerbate inflammation, causing tissue damage.

Kidney Involvement

• Immune complexes deposited in the kidneys can lead to glomerulonephritis, a type of kidney disease.

Serum Sickness

• Serum sickness is caused by the formation of immune complexes, which trigger an immune response, leading to symptoms such as fever, rash, and arthritis.

Localized Disease

• In Type III Immune Complex Disease, localized disease occurs when immune complexes deposit in specific tissues, triggering a local inflammatory response.

Delayed Type Hypersensitivity (DTH)

• The primary mechanism behind DTH is the activation of T cells, which release cytokines, leading to the recruitment of macrophages and other immune cells.

Consequences of Macrophage Activation

• Continued macrophage activation in DTH can lead to tissue damage and chronic inflammation.

Sensitization Stage of Type IV DTH

• During sensitization, memory Th1 cells play a crucial role in recognizing and responding to specific antigens.

Cytokine Production in Type IV DTH

• Activated Th1 memory cells produce cytokines such as IFN-γ and TNF-α during secondary exposure in Type IV DTH.

Contact Dermatitis

• Contact dermatitis is a type of Type IV DTH reaction, which occurs when the skin comes into contact with an allergen, triggering a delayed immune response.

This quiz covers the formation and consequences of immune complex diseases, focusing on Type III immune complexes and the role of phagocytes. Topics include the deposition of complexes in capillaries, inflammation triggers, and the concept of 'frustrated phagocytes'.