The Journal of Immunology, Vol 154, Issue 8 3678-3685, Copyright © 1995 by American Association of Immunologists

ARTICLES

pp60c-src expression is induced by activation of normal human T lymphocytes [published erratum appears in J Immunol 1995 Aug 1;155(3):1637]

DR Branch and GB Mills
Research Section, Canadian Red Cross Society, Toronto, Ontario.

We have re-examined whether pp60c-src, the normal cellular homologue of the transforming protein of Rous sarcoma virus, is present in human T cells. By in vitro immune-complex kinase assay or Western blotting with the anti-pp60c-src mAbs 327 or GD11, pp60c-src was found to be present in lysates of T cell lines, including the Jurkat T cell line. The 327 and GD11 mAbs have been reported to be specific for pp60c-src and not to cross-react with other src family members or other kinases. Furthermore, the size of the pp60c-src bands present on Western blotting and in vitro kinase assay were clearly different from those of p56lck or p59fyn. In addition, pp60c-src is detected in the HTLV-I- derived T cell lines S1T and C8, which lack expression of p56lck and p59fyn. RNase protection assays confirmed that pp60c-src mRNA is present in Jurkat T cells. We also found pp60c-src protein to be constitutively present in freshly isolated thymocytes. In contrast, pp60c-src was absent, or present at extremely low levels, in normal, resting peripheral blood T lymphocytes, which is in agreement with previous findings. However, after stimulation of resting T cells with the mitogenic lectin PHA or with Ab to the TCR complex, pp60c-src expression is induced in both CD4+ and CD8+ T cell subsets, with peak expression detectable 12 to 24 h after T cell activation. The levels of pp60c-src are low in all T cells except Jurkat, where levels of pp60c- src are comparable to levels found in a glioblastoma cell line (T98G). Nevertheless, significant levels of pp60c-src kinase activity are readily detectable in thymocytes and activated normal T cells as well as in T cell lines. The finding that pp60c-src is inducible following activation through the TCR suggests that pp60c-src may play a specific role in the normal T cell activation pathway.

This article has been cited by other articles:

				G. Suck, D. R. Branch, P. Aravena, M. Mathieson, S. Helke, and A. Keating Constitutively polarized granules prime KHYG-1 NK cells Int. Immunol., September 1, 2006; 18(9): 1347 - 1354. [Abstract] [Full Text] [PDF]

				S. Neron, G. Suck, X.-Z. Ma, D. Sakac, A. Roy, Y. Katsman, N. Dussault, C. Racine, and D. R. Branch B cell proliferation following CD40 stimulation results in the expression and activation of Src protein tyrosine kinase Int. Immunol., February 1, 2006; 18(2): 375 - 387. [Abstract] [Full Text] [PDF]

				D. Cussac, C. Greenland, S. Roche, R.-Y. Bai, J. Duyster, S. W. Morris, G. Delsol, M. Allouche, and B. Payrastre Nucleophosmin-anaplastic lymphoma kinase of anaplastic large-cell lymphoma recruits, activates, and uses pp60c-src to mediate its mitogenicity Blood, February 15, 2004; 103(4): 1464 - 1471. [Abstract] [Full Text] [PDF]

				J. B. Pollett, S. Trudel, D. Stern, Z. H. Li, and A. K. Stewart Overexpression of the myeloma-associated oncogene fibroblast growth factor receptor 3 confers dexamethasone resistance Blood, November 15, 2002; 100(10): 3819 - 3821. [Abstract] [Full Text] [PDF]

				M.-R. Chen, S.-J. Chang, H. Huang, and J.-Y. Chen A Protein Kinase Activity Associated with Epstein-Barr Virus BGLF4 Phosphorylates the Viral Early Antigen EA-D In Vitro J. Virol., April 1, 2000; 74(7): 3093 - 3104. [Abstract] [Full Text]

				E. E. Plowright, Z. Li, P. L. Bergsagel, M. Chesi, D. L. Barber, D. R. Branch, R. G. Hawley, and A. K. Stewart Ectopic expression of fibroblast growth factor receptor 3 promotes myeloma cell proliferation and prevents apoptosis Blood, February 1, 2000; 95(3): 992 - 998. [Abstract] [Full Text] [PDF]

				D. J. Phipps, S. Yousefi, and D. R. Branch Increased Enzymatic Activity of the T-Cell Antigen Receptor-Associated Fyn Protein Tyrosine Kinase in Asymptomatic Patients Infected With the Human Immunodeficiency Virus Blood, November 1, 1997; 90(9): 3603 - 3612. [Abstract] [Full Text] [PDF]

				A. August, A. Sadra, B. Dupont, and H. Hanafusa Src-induced activation of inducible T cell kinase (ITK) requires phosphatidylinositol 3-kinase activity and the Pleckstrin homology domain of inducible T cell kinase PNAS, October 14, 1997; 94(21): 11227 - 11232. [Abstract] [Full Text] [PDF]

				A.-K. Somani, J. S. Bignon, G. B. Mills, K. A. Siminovitch, and D. R. Branch Src Kinase Activity Is Regulated by the SHP-1 Protein-tyrosine Phosphatase J. Biol. Chem., August 22, 1997; 272(34): 21113 - 21119. [Abstract] [Full Text] [PDF]

				S. Gibson, A. August, D. Branch, B. Dupont, and G. B. Mills Functional LCK Is Required for Optimal CD28-mediated Activation of the TEC Family Tyrosine Kinase EMT/ITK J. Biol. Chem., March 22, 1996; 271(12): 7079 - 7083. [Abstract] [Full Text] [PDF]