Title: light chain
Long Title: IUPAC Gold Book - light chain
DOI: 10.1351/goldbook.13386
Status: current

Definition
Small polypeptide subunit of an antibody or immunoglobulin (Ig).

Note
A typical antibody is composed of two immunoglobulin (Ig) heavy chains and two Ig light chains.

Related Term
- heavy chains: https://goldbook.iupac.org/terms/view/13198

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1202 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13386/html
- json: https://goldbook.iupac.org/terms/view/13386/json
- xml: https://goldbook.iupac.org/terms/view/13386/xml

Citation: Citation: 'light chain' 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.13386
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Accessed: 2026-06-28T15:53:43+00:00