T lymphocyte

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 cell

T lymphocytes differentiate in the thymus and interact directly with other cells to regulate the immune response or to kill cells expressing the appropriate antigen.

—Alan F. Williams

Activation of a T lymphocyte requires occupancy of its antigen-specific cell surface receptor … by its appropriate ligand (processed antigen presented by class I or class II MHC molecules) and a second signal from a growth factor.

—Suryaprakash R. Sambhara et al.

compare b lymphocyte

Examples of T lymphocyte in a Sentence

Recent Examples on the Web

His physician, David Golde of UCLA, found a rare T lymphocyte in Moore’s blood that could be coaxed into making an immune-boosting protein. —Delthia Ricks, Discover Magazine, 27 Jan. 2010

Word History

Etymology

thymus-derived

First Known Use

1972, in the meaning defined above

Kids Definition

T lymphocyte

noun

: T cell

Medical Definition

T lymphocyte

noun

ˈtē- 

: t cell