Title: isotype switch
Long Title: IUPAC Gold Book - isotype switch
DOI: 10.1351/goldbook.13349
Status: current

Definition
Process by which a B cell switches from making antibody of one isotype to another without altering the specificity of the antibody, producing an isotype with the same variable (V) regions but a different heavy chain constant (C) region.

Related Terms
- B cell: https://goldbook.iupac.org/terms/view/12937
- constant (C) region: https://goldbook.iupac.org/terms/view/13039
- heavy chain: https://goldbook.iupac.org/terms/view/13198
- isotype: https://goldbook.iupac.org/terms/view/13347
- variable (V) regions: https://goldbook.iupac.org/terms/view/13773

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1197 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13349/html
- json: https://goldbook.iupac.org/terms/view/13349/json
- xml: https://goldbook.iupac.org/terms/view/13349/xml

Citation: Citation: 'isotype switch' 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.13349
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Accessed: 2026-05-14T03:36:37+00:00