Lck plays a critical role in Ca(2+) mobilization and CD28 costimulation in mature primary T cells.
To investigate the signaling function of the Src-family protein tyrosine kinase Lck in mature T cells, we generated transgenic mice that expressed Lck in thymocytes but not in peripheral lymphocytes. We compared the phenotype and signaling capacity of Lck-deficient T cells with T cells from mice expressing a dominant inhibitory form of Lck and found that both mouse strains have diminished numbers of mature CD8(+) T cells and respond poorly to CD28 costimulation. However, while T cells that lack Lck fail to mobilize Ca(2+) after stimulation, those expressing the dominant negative protein do so normally. Our data demonstrate that Lck plays several unique roles in mature lymphocyte signaling.
Trobridge
P A
PA
Department of Immunology, University of Washington, Seattle, WA 98195, USA.
Levin
S D
SD
D000818:Animals; D018106:CD28 Antigens / Q000502:physiology*; D002118:Calcium / Q000378:metabolism*; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D013601:T-Lymphocytes / Q000502:physiology*
D018106:CD28 Antigens; D007376:Interleukin-2; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D002118:Calcium