Definitions for "Co-stimulation"
The proliferation of T lymphocytes usually requires both antigen binding and a second signal, normally delivered by a cell surface molecule on an antigen-presenting cell. Antigen and cell surface ligand can be substituted for by monoclonal antibodies with specificity for the TCR and a secondary, “costimulatory” receptor (most prominently CD28).
The delivery of a second signal from an antigen-presenting cell to a T cell. The second signal rescues the activated T cell from anergy, allowing it to produce the lymphokines necessary for the growth of additional T cells.
signals in addition to those through the antigen receptor that are required for full T lymphocyte acitvation