Types of hypersensitivity reactions

1. Immune complex-mediated hypersensitivity

1.1. Immune complexes

1.1.1. Ag-Ab complexes deposited in various tissues induce complement activation

1.1.2. ensuing inflammatory response

1.1.2.1. massive infiltration of neutrophils.

1.1.2.1.1. Rheumatoid arthritis

1.1.2.1.2. Systemic lupus

2. Delayed type hypersensitivity (DTH)

2.1. T cells

2.2. release cytokines

2.2.1. macrophages

2.2.2. Tc cells

2.2.3. direct cellular damage

2.2.3.1. Tuberculin

2.2.3.2. Multiple sclerosis

3. Allergy and Atopy

3.1. IgE

3.1.1. bound to mast cells and basophils

3.1.2. release of vasoactive mediators

3.1.2.1. Hay fever

3.1.2.2. Asthma

4. Antibody-mediated hypersensitivity

4.1. IgG

4.1.1. IgM

4.1.2. Ab directed against cell surface antigens

4.1.2.1. mediates cell destruction

4.1.2.1.1. complement activation

4.1.2.1.2. ADCC.