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
Gina KolataT cells recognize antigen only in association with cell surface molecules encoded by the major histocompatibility complex …—Miranda Robertson
see helper t cell, killer t cell compare b cell
Miranda RobertsonExamples of T cell in a Sentence
Recent Examples on the Web
T cells normally recognize other cells that have been infected by a virus or bacterium, or are otherwise abnormal, and either destroy them or recruit other parts of the immune system to do so.
—Amber Dance, ArsTechnica, 17 May 2026
Those two strong responders saw their HIV drop to undetectable levels, inching up only occasionally when the CAR-T cells presumably got to work again.
—ABC News, 12 May 2026
B cells identify cancer cells and send the signal to T cells to go in and attack.
—Ashley MacKin Solomon, San Diego Union-Tribune, 8 May 2026
What multiple doctors had written off as dry skin was, in fact, cutaneous T-cell lymphoma, a rare type of non-Hodgkin lymphoma that starts in white blood cells called T cells and primarily affects the skin, according to the Cleveland Clinic.
—Jordan Greene, PEOPLE, 4 May 2026
See All Example Sentences for T cell
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Amber Dance, ArsTechnica, 17 May 2026
Those two strong responders saw their HIV drop to undetectable levels, inching up only occasionally when the CAR-T cells presumably got to work again.
—ABC News, 12 May 2026
B cells identify cancer cells and send the signal to T cells to go in and attack.
—Ashley MacKin Solomon, San Diego Union-Tribune, 8 May 2026
What multiple doctors had written off as dry skin was, in fact, cutaneous T-cell lymphoma, a rare type of non-Hodgkin lymphoma that starts in white blood cells called T cells and primarily affects the skin, according to the Cleveland Clinic.
—Jordan Greene, PEOPLE, 4 May 2026
See All Example Sentences for T cell
Cite this Entry
“T cell.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/T%20cell. Accessed 22 May. 2026.
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