Title: host defense
Long Title: IUPAC Gold Book - host defense
DOI: 10.1351/goldbook.13226
Status: current

Definition
Ability of an individual to resist invasion by opportunistic agents and production of disease associated with exposure to microorganisms, foreign tissue, and particulates, as well as certain types of neoplasia. Host defense may be either nonspecific (innate or natural immunity) or specific (adaptive or acquired immunity) in nature.

Note
Immunological defense may involve chemotaxis, phagocytosis, reaction with immunoglobulins (Ig) and/or with complement, and T-cell cytotoxicity.

Related Terms
- T-cell: https://goldbook.iupac.org/terms/view/13724
- acquired immunity: https://goldbook.iupac.org/terms/view/12832
- adaptive: https://goldbook.iupac.org/terms/view/12843
- chemotaxis: https://goldbook.iupac.org/terms/view/13000
- cytotoxicity: https://goldbook.iupac.org/terms/view/12993
- innate: https://goldbook.iupac.org/terms/view/13335
- natural immunity: https://goldbook.iupac.org/terms/view/13498
- phagocytosis: https://goldbook.iupac.org/terms/view/13562

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1177 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13226/html
- json: https://goldbook.iupac.org/terms/view/13226/json
- xml: https://goldbook.iupac.org/terms/view/13226/xml

Citation: Citation: 'host defense' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.13226
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Accessed: 2026-06-30T06:10:13+00:00