Immunodeficiency Disorders and Hypersensitivity

This set of flashcards covers key vocabulary and definitions related to immunodeficiency disorders and hypersensitivity themes discussed in the lecture.

Immunodeficiency

A deficiency in the immune response resulting in failure to protect the host from disease.

Primary Immunodeficiency (PID)

Immunodeficiency resulting from an inherited genetic or developmental defect.

Severe Combined Immunodeficiency (SCID)

The most extreme form of CID characterized by a nearly complete loss of functional T cells.

X-Linked SCID (XSCID)

The most common form of SCID caused by a mutation in IL-2R.

Common Variable Immunodeficiencies (CVIDs)

Genetic defects resulting in low levels of most or all antibody classes.

Secondary (Acquired) Immunodeficiency

Loss of immune function due to exposure to an external agent.

Human Immunodeficiency Virus (HIV)

A viral infection that leads to loss of key immune cells, marked deficiency in cell-mediated immune responses.

Hypersensitivity

An inappropriate immune response to antigens that pose little or no threat.

Type I Hypersensitivity

Allergic reaction initiated by IgE antibodies involving mast cells, basophils, and eosinophils.

Sensitization

The process of arming mast cells with allergen-specific IgE antibodies.

Antihistamines

Drugs that prevent histamine from binding to H1 receptors and mitigate allergic reactions.

Type II Hypersensitivity

Antibody-mediated destruction of cells in response to reactive small molecules.

Type III Hypersensitivity

Initiated by immune complexes of antigens and IgG, leading to tissue damage.

Type IV Hypersensitivity

T cell mediated hypersensitivity, with delayed reactions manifesting hours or days after exposure.