1. Define hypersensitivity.

2. What does hypersensitivity result in?

1. The altered immunologic response to an antigen.

2. Hypersensitivity results in damage or disease.

Name the type, name, antibody, timing, and effector cells. 

Type    Name                 AB     Timing         Effector cells

1         IgE mediated      IgE     immediate   Mast

2         Tissue Specific   IgG&M  immediate   Macrophages

3         Immune complex  IgG&M immediate  Neutrophils

4         Cell mediated     --------  delayed      lymphocytes

                                                               macrphgs

Contrast autoimmunity and alloimmunity.

Autoimmunity is when the immune system acts againt self or own cells.

Alloimmunity is an immune reaction to tissues of another individual (ex. liver or kidney transplant).

What are the inappropriate immune responses?

AAA (like triple A)

 Autoimmunity, alloimmunity, and allergies.

What is an allergy?

the most common type of exaggerated immune response to an environmental antigen, but least life threatening.

What are the kinds of hypersensitivity?

IDA

Immediate hypersensitivity- reactions that occur w/i minutes to a few hrs after exposure

Delayed hypersensitivity- reactions that occur several hours after exposure to appear; max severity occurs days after exposure to the antigen.

Anaphylaxis-- most rapid and severe immed. hypersensitivity reaction. Occurs w/i minutes of re-exposure.  Can be systemic (generalized) or localized (cutaneous)

What does the severity of anaphylaxis depend on?

How soon does anaphlaxis occur?

• Severity of anaphylaxis depends on the level of sensitization.  Can be a small dose of ordinary skin testing.
• Occurs w/i minutes after re-exposure.

What are the localized symptoms of anaphylaxis?

RSP

Redness

Swelling

Pain

What are the systemic (localized) symptoms of anaphylaxis (overreaction to antigen)?

HIVED

• Hives
• Itching
• Vomit, abdominal cramps, diarrhea
• Erythema (redness)
• Difficulty breathing

What happens to the body in the case of severe anaphylaxis?

• Respiratory distress
• Shock
• Vascular collapse-- decrease in BP
• Laryngeal edema
• Contraction of bronchial smooth muscle
• Death

What can cause the onset of anaphylaxis?

Shellfish/fish, peanuts and other nuts, milk, eggs, medications

Describe Type 1 hypersensitivity.

• is IgE mediated
• products of tissue mast cells
• most common allergy b/c they are environmental allergens
• has short life span in blood
• rapidly binds to Fc receptors on surface of mast cells
• histamine is most potent receptor
• h1 receptor: contracts bronchial smooth muscle, increases vascular permability, causes vasodiliation to area
• h2 receptor: increases gastric acid secretion

What parts of the body does type 1 hypersensitivity affect?

What are the symptoms?

GI, skin, and respiratory tract

symptoms:

hives (urticaria), itching, hypotension, rhinitis (runny nose), bronchospasm, conjunctivis, wheel and flare reaction

GI: vomiting, diahrrea, abdominal cramping

What causes type II hypersensitivity?