Title: helper T lymphocyte
Long Title: IUPAC Gold Book - helper T lymphocyte
DOI: 10.1351/goldbook.13199
Status: current

Definition
Member of a subclass of T lymphocytes that provides help (in the form of cytokines and/or cognate interactions) necessary for the expression of effector function by other cells in the immune system.

Note
Helper T cells recognize antigen in association with major histocompatibility complex (MHC) class II gene products. Depending on their capacity to produce various cytokines, one can functionally differentiate Th1 [interleukin-2- (IL-2-) and IFN-γ-producing] and Th2 (interleukins IL-3-, IL-4-, and IL-6-producing) cells.

Related Terms
- IFN-γ: https://goldbook.iupac.org/terms/view/13163
- T lymphocytes: https://goldbook.iupac.org/terms/view/13724
- Th1: https://goldbook.iupac.org/terms/view/13718
- Th2: https://goldbook.iupac.org/terms/view/13719
- cytokines: https://goldbook.iupac.org/terms/view/13065
- immune system: https://goldbook.iupac.org/terms/view/13271
- interleukin: https://goldbook.iupac.org/terms/view/13338
- major histocompatibility complex (MHC) class II: https://goldbook.iupac.org/terms/view/13432

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1173 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13199/html
- json: https://goldbook.iupac.org/terms/view/13199/json
- xml: https://goldbook.iupac.org/terms/view/13199/xml

Citation: Citation: 'helper T lymphocyte' 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.13199
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Accessed: 2026-06-30T12:00:56+00:00