T cell

noun

: any of several lymphocytes (such as a helper T cell) that differentiate in the thymus, possess highly specific cell-surface antigen receptors, and include some that control the initiation or suppression of cell-mediated and humoral immunity (as by the regulation of T and B cell maturation and proliferation) and others that lyse antigen-bearing cells : t lymphocyte
The immature lymphoid cell, in turn, can be processed into a B cell, which makes infection-fighting antibodies, or a T cell, which recognizes foreign tissue and virally infected cells and directs the activities of the rest of the immune system.Gina Kolata
T cells recognize antigen only in association with cell surface molecules encoded by the major histocompatibility complexMiranda Robertson
see helper t cell, killer t cell compare b cell

Examples of T cell in a Sentence

Recent Examples on the Web But over the last few years, researchers in Germany have begun testing the potential of CAR-T therapy — a cutting-edge cancer treatment in which a patient’s immune T cells are genetically modified in a lab to better attack disease targets — to help those with autoimmune disorders. Theresa Gaffney, STAT, 21 Feb. 2024 Evidence of Gene-Editing The lentiviral and enveloped delivery vectors successfully transformed a percentage of T cells into CAR-bearing T cells. William A. Haseltine, Forbes, 14 Feb. 2024 If these are from an invader, such as a virus, or show the cell is otherwise malfunctioning, this signals the immune system T cells to respond.2 The Role of Antigens Antigens are immune response initiators. Angelica Bottaro, Verywell Health, 16 Jan. 2024 The acids, in turn, weakened the animals’ T cells — immune-system warriors that go rogue in autoimmune disorders. Kenneth Miller, Discover Magazine, 11 Dec. 2023 The treatment involves intravenous drips of the patient’s own T cells, reëngineered in a laboratory to bind with specific antigens on the surface of the patient’s cancer cells. Casey Cep, The New Yorker, 4 Dec. 2023 According to the National Cancer Institute, the treatment involves replicating a patient’s T cells — a type of white blood cell — and reprogramming them so they can be infused back into the patient to target and kill the cancer cells. Julia Moore, Peoplemag, 30 Nov. 2023 Now, the agency is probing reports of some patients’ T cells becoming cancerous after receiving these therapies. Emily Mullin, WIRED, 29 Nov. 2023 One possibility relates to the viruses used to engineer patients’ T cells, which could be straying from their targets. Damian Garde, STAT, 29 Nov. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'T cell.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

thymus-derived cell

First Known Use

1970, in the meaning defined above

Time Traveler
The first known use of T cell was in 1970

Dictionary Entries Near T cell

Cite this Entry

“T cell.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/T%20cell. Accessed 19 Mar. 2024.

Kids Definition

T cell

noun
: any of the lymphocytes (as a helper T cell) that usually mature in the thymus and take an active part in immune responses compare b cell

Medical Definition

T cell

noun
: any of several lymphocytes (as a helper T cell) that differentiate in the thymus, possess highly specific cell-surface antigen receptors, and include some that control the initiation or suppression of cell-mediated and humoral immunity (as by the regulation of T and B cell maturation and proliferation) and others that lyse antigen-bearing cells

called also T lymphocyte

see cytotoxic t cell, helper t cell, suppressor t cell, t4 cell

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