|
|
||||||||
Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
Requirements for T cell activation are not fully established. One model is that receptor occupancy and down-regulation are essential for activation, and another, not necessarily mutually exclusive, model is that sustained signals are important. Here we examine the importance of signal duration in T cell activation. First, we demonstrate that immobilized, but not soluble cross-linked, Abs to CD3 stimulate degranulation by CTL. The cross-linked Abs are not deficient in their ability to signal since they stimulate the same tyrosine phosphorylation pattern as immobilized Ab, but it is very transient relative to that stimulated by immobilized Ab. Furthermore, novel decreased migratory forms of Lck occur to a significant extent only after stimulation with immobilized Abs. A dramatic difference in the duration of signals is very evident when mitogen-activated protein kinase (MAPK) activity is examined. Immobilized anti-CD3 stimulates very high levels of MAPK activation that is still detectable 1 h after stimulation. In contrast, cross-linked Ab stimulates only transient and incomplete activation of MAPK. Taken together, these results suggest that TCR engagement and induction of tyrosine phosphorylation alone are not sufficient for T cell activation and that the duration of TCR-stimulated signals is critical to attain a functional response.
This article has been cited by other articles:
![]() |
X. Wang, L. Simeoni, J. A. Lindquist, J. Saez-Rodriguez, A. Ambach, E. D. Gilles, S. Kliche, and B. Schraven Dynamics of Proximal Signaling Events after TCR/CD8-Mediated Induction of Proliferation or Apoptosis in Mature CD8+ T Cells J. Immunol., May 15, 2008; 180(10): 6703 - 6712. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-S. He and H. L. Ostergaard CTLs Contain and Use Intracellular Stores of FasL Distinct from Cytolytic Granules J. Immunol., August 15, 2007; 179(4): 2339 - 2348. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Grybko, J. P. Bartnik, G. A. Wurth, A. T. Pores-Fernando, and A. Zweifach Calcineurin Activation Is Only One Calcium-dependent Step in Cytotoxic T Lymphocyte Granule Exocytosis J. Biol. Chem., June 22, 2007; 282(25): 18009 - 18017. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. S. Y. Ma, N. Monu, D. T. Shen, I. Mecklenbrauker, N. Radoja, T. F. Haydar, M. Leitges, A. B. Frey, S. Vukmanovic, and S. Radoja Protein Kinase C{delta} Regulates Antigen Receptor-Induced Lytic Granule Polarization in Mouse CD8+ CTL J. Immunol., June 15, 2007; 178(12): 7814 - 7821. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Grybko, A. T. Pores-Fernando, G. A. Wurth, and A. Zweifach Protein kinase C activity is required for cytotoxic T cell lytic granule exocytosis, but the {theta} isoform does not play a preferential role J. Leukoc. Biol., February 1, 2007; 81(2): 509 - 519. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Laforge, N. Bidere, S. Carmona, A. Devocelle, B. Charpentier, and A. Senik Apoptotic Death Concurrent with CD3 Stimulation in Primary Human CD8+ T Lymphocytes: A Role for Endogenous Granzyme B J. Immunol., April 1, 2006; 176(7): 3966 - 3977. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. K. Robertson, L. R. Mireau, and H. L. Ostergaard A Role for Phosphatidylinositol 3-Kinase in TCR-Stimulated ERK Activation Leading to Paxillin Phosphorylation and CTL Degranulation J. Immunol., December 15, 2005; 175(12): 8138 - 8145. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. L. Lysechko and H. L. Ostergaard Differential Src Family Kinase Activity Requirements for CD3{zeta} Phosphorylation/ZAP70 Recruitment and CD3{epsilon} Phosphorylation J. Immunol., June 15, 2005; 174(12): 7807 - 7814. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Sipione, C. Ewen, I. Shostak, M. Michalak, and R. C. Bleackley Impaired Cytolytic Activity in Calreticulin-Deficient CTLs J. Immunol., March 15, 2005; 174(6): 3212 - 3219. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. F. Fierro, G. A. Wurth, and A. Zweifach Cross-talk with Ca2+ Influx Does Not Underlie the Role of Extracellular Signal-regulated Kinases in Cytotoxic T Lymphocyte Lytic Granule Exocytosis J. Biol. Chem., June 11, 2004; 279(24): 25646 - 25652. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. O. Yarovinsky, M. M. Monick, and G. W. Hunninghake Integrin Receptors Are Crucial for the Restimulation of Activated T Lymphocytes Am. J. Respir. Cell Mol. Biol., May 1, 2003; 28(5): 607 - 615. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. G. Puente and H. L. Ostergaard {beta}1/{beta}3 integrin ligation is uncoupled from ERK1/ERK2 activation in cytotoxic T lymphocytes J. Leukoc. Biol., March 1, 2003; 73(3): 391 - 398. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. D. Edmonds and H. L. Ostergaard Dynamic Association of CD45 with Detergent-Insoluble Microdomains in T Lymphocytes J. Immunol., November 1, 2002; 169(9): 5036 - 5042. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Borovsky, G. Mishan-Eisenberg, E. Yaniv, and J. Rachmilewitz Serial Triggering of T Cell Receptors Results in Incremental Accumulation of Signaling Intermediates J. Biol. Chem., June 7, 2002; 277(24): 21529 - 21536. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Favier, N. J. Burroughs, L. Wedderburn, and S. Valitutti TCR dynamics on the surface of living T cells Int. Immunol., December 1, 2001; 13(12): 1525 - 1532. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. S. Warren, A. J. Campbell, J. C. Waldron, and L. L. Lanier Biphasic response of NK cells expressing both activating and inhibitory killer Ig-like receptors Int. Immunol., August 1, 2001; 13(8): 1043 - 1052. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. R. Santori, I. Arsov, and S. Vukmanovic Modulation of CD8+ T Cell Response to Antigen by the Levels of Self MHC Class I J. Immunol., May 1, 2001; 166(9): 5416 - 5421. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. G. Puente, J. C. Stone, and H. L. Ostergaard Evidence for Protein Kinase C-Dependent and -Independent Activation of Mitogen-Activated Protein Kinase in T Cells: Potential Role of Additional Diacylglycerol Binding Proteins J. Immunol., December 15, 2000; 165(12): 6865 - 6871. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. A. Fischer, A. Palmetshofer, S. Gambaryan, E. Butt, C. Jassoy, U. Walter, S. Sopper, and S. M. Lohmann Activation of cGMP-dependent Protein Kinase Ibeta Inhibits Interleukin 2 Release and Proliferation of T Cell Receptor-stimulated Human Peripheral T Cells J. Biol. Chem., February 16, 2001; 276(8): 5967 - 5974. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |