Title: B7 molecule
Long Title: IUPAC Gold Book - B7 molecule
DOI: 10.1351/goldbook.12933
Status: current

Definition
Co-stimulatory molecule on the surface of T-cell-activating antigen-presenting cells (APCs), allowing full activation of T cells that are bound to major histocompatibility complex (MHC)-peptide complexes.

Note
Whereas binding of B7 molecules to CD28 is stimulatory, binding to cytotoxic T-lymphocyte antigen-4 (CTLA-4) decreases T-cell activity and participates in tolerance.

Related Terms
- Co-stimulatory molecule: https://goldbook.iupac.org/terms/view/13051
- T-cell: https://goldbook.iupac.org/terms/view/13724
- activation: https://goldbook.iupac.org/terms/view/13401
- antigen-presenting cells (APCs): https://goldbook.iupac.org/terms/view/12888
- cytotoxic T-lymphocyte antigen-4 (CTLA-4): https://goldbook.iupac.org/terms/view/13073
- major histocompatibility complex (MHC): https://goldbook.iupac.org/terms/view/13430
- tolerance: https://goldbook.iupac.org/terms/view/13302

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1132 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/12933/html
- json: https://goldbook.iupac.org/terms/view/12933/json
- xml: https://goldbook.iupac.org/terms/view/12933/xml

Citation: Citation: 'B7 molecule' 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.12933
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Accessed: 2026-05-14T13:49:46+00:00