NU 231 Chapter 12: Disorders of the Immune Response

Vocabulary flashcards covering key terms and concepts related to immune response disorders and Type I immediate hypersensitivity.

Immune System

A system designed to protect from invading organisms (antigens) and maintain homeostasis by distinguishing self from non-self.

Hypersensitivity Disorders

Exaggerations of the adaptive immune response consisting of four types (I-IV) that result in host damage and range from mild to life-threatening.

Autoimmunity

An immune response disorder where the immune system fails to maintain homeostasis by distinguishing self from non-self.

Type I Immediate Hypersensitivity Disorders

Disorders caused by genetic factors and environmental triggers, characterized by IgE binding to mast cells, degranulation, release of histamine, and recruitment of eosinophils to the area.

Sensitization of Mast Cell

The process in Type I hypersensitivity where an antigen prompts CD4 $T_H2$ cells to release IL-3, IL-4, and IL-5, inducing B cells to become IgE-secreting plasma cells whose antibodies bind to mast cells.

Primary Early Response

The initial phase of Type I hypersensitivity involving mast cell degranulation and release of mediators, resulting in vasodilation, vascular damage, and smooth muscle spasm.

Secondary Late Response

The second phase of Type I hypersensitivity involving cytokine release, eosinophil recruitment, leukocyte infiltration, and arachidonic acid production (prostaglandins and leukotrienes), resulting in mucosal edema, mucus secretion, epithelial damage, and bronchospasm.

Arachidonic Acid

A compound generated from membrane phospholipids during the secondary late response of Type I hypersensitivity that produces prostaglandins and leukotrienes.