Title: immunological memory
Long Title: IUPAC Gold Book - immunological memory
DOI: 10.1351/goldbook.13300
Status: current

Definition
Ability of the immune system to respond faster and more effectively to subsequent exposures to an antigen following a primary immune response to the same antigen.

Note
Typically, memory T cells appear five days following initial immunization, whereas memory B cells may take about a month to reach maximum levels. Populations of such cells may persist for the lifetime of the individual.

Related Terms
- immune system: https://goldbook.iupac.org/terms/view/13271
- memory B cells: https://goldbook.iupac.org/terms/view/13451
- memory T cells: https://goldbook.iupac.org/terms/view/13452
- primary immune response: https://goldbook.iupac.org/terms/view/13601

Source
- PAC, 2012, 84, 1113. 'IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)' on page 1189 (https://doi.org/10.1351/PAC-REC-11-06-03)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/13300/html
- json: https://goldbook.iupac.org/terms/view/13300/json
- xml: https://goldbook.iupac.org/terms/view/13300/xml

Citation: Citation: 'immunological memory' 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.13300
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Accessed: 2026-06-28T22:04:53+00:00