Title: Gell and Coombs classification
Long Title: IUPAC Gold Book - Gell and Coombs classification
DOI: 10.1351/goldbook.13167
Status: current

Definition
Classification of immune mechanisms of tissue injury into four types: type I, immediate-type hypersensitivity reactions, mediated by interaction of immunoglobulin E (IgE) antibody and antigen causing the release of histamine and other mediators; type II, antibody-mediated hypersensitivity reactions, due to antibody–antigen interactions on cell surfaces; type III, immune complex, local or general inflammatory responses due to formation of circulating immune complexes and their deposition in tissues; and type IV cell-mediated hypersensitivity reactions, initiated by sensitized T lymphocytes either by release of lymphokines or by T-cell-mediated cytotoxicity [see cytotoxic T lymphocyte (CTL)].

Related Terms
- T lymphocytes: https://goldbook.iupac.org//terms/view/13724
- cytotoxic T lymphocyte (CTL): https://goldbook.iupac.org//terms/view/13072
- hypersensitivity: https://goldbook.iupac.org//terms/view/13241
- immediate-type hypersensitivity: https://goldbook.iupac.org//terms/view/13255
- immune complex: https://goldbook.iupac.org//terms/view/13257
- immunoglobulin E (IgE): https://goldbook.iupac.org//terms/view/13288
- lymphokines: https://goldbook.iupac.org//terms/view/13415

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1168 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13167/html
- json: https://goldbook.iupac.org/terms/view/13167/json
- xml: https://goldbook.iupac.org/terms/view/13167/xml

Citation: Citation: 'Gell and Coombs classification' 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.13167
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Accessed: 2026-07-14T09:14:17+00:00