Summarizing Disruptions in the Immune System

Summary

Immune disruptions may involve insufficient immune responses or inappropriate immune targets. Immunodeficiency increases an individual's susceptibility to infections and cancers. Hypersensitivities are misdirected responses either to harmless foreign particles, as in the case of allergies, or to host factors, as in the case of autoimmunity. Reactions to self components may be the result of molecular mimicry.

Glossary

allergy

immune reaction that results from immediate hypersensitivities in which an antibody-mediated immune response occurs within minutes of exposure to a harmless antigen

autoantibody

antibody that incorrectly marks “self” components as foreign and stimulates the immune response

autoimmunity

type of hypersensitivity to self antigens

hypersensitivities

spectrum of maladaptive immune responses toward harmless foreign particles or self antigens; occurs after tissue sensitization and includes immediate-type (allergy), delayed-type, and autoimmunity

immunodeficiency

failure, insufficiency, or delay at any level of the immune system, which may be acquired or inherited