| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
*
Department of Cellular and Developmental Biology, "La Sapienza" University, Rome, Italy; and
Department of Immunology, Imperial College of Medicine, Hammersmith Hospital, London, United Kingdom
T cell suppression exerted by regulatory T cells represents a well-established phenomenon, but the mechanisms involved are still a matter of debate. Recent data suggest that anergic T cells can suppress responder T cell activation by inhibiting Ag presentation by dendritic cells (DC). In this study, we focused our attention on the mechanisms that regulate the susceptibility of DC to suppressive signals and analyzed the fate of DC and responder T cells. To address this issue, we have cocultured human alloreactive or Ag-specific CD4+ T cell clones, rendered anergic by incubation with immobilized anti-CD3 Ab, with autologous DC and responder T cells. We show that anergic T cells affect either Ag-presenting functions or survival of DC, depending whether immature or mature DC are used as APC. Indeed, MHC and costimulatory molecule expression on immature DC activated by responder T cells is inhibited, while apoptotic programs are induced in mature DC and in turn in responder T cells. Ligation of CD95 by CD95L expressed on anergic T cells in the absence of CD40-CD40L (CD154) interaction are critical parameters in eliciting apoptosis in both DC and responder T cells. In conclusion, these findings indicate that the defective activation of CD40 on DC by CD95L+ CD154-defective anergic T cells could be the primary event in determining T cell suppression and support the role of CD40 signaling in regulating both conditioning and survival of DC.
This article has been cited by other articles:
|
|
 |
|
  M. Carvalho-Gaspar, N. D. Jones, S. Luo, L. Martin, M. O. Brook, and K. J. Wood Location and Time-Dependent Control of Rejection by Regulatory T Cells Culminates in a Failure to Generate Memory T Cells J. Immunol., May 15, 2008; 180(10): 6640 - 6648. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Frasca, M. Nasso, F. Spensieri, G. Fedele, R. Palazzo, F. Malavasi, and C. M. Ausiello IFN-{gamma} Arms Human Dendritic Cells to Perform Multiple Effector Functions J. Immunol., February 1, 2008; 180(3): 1471 - 1481. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. P. Lewkowich, N. S. Herman, K. W. Schleifer, M. P. Dance, B. L. Chen, K. M. Dienger, A. A. Sproles, J. S. Shah, J. Kohl, Y. Belkaid, et al. CD4+CD25+ T cells protect against experimentally induced asthma and alter pulmonary dendritic cell phenotype and function J. Exp. Med., December 5, 2005; 202(11): 1549 - 1561. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Mallone, S. A. Kochik, H. Reijonen, B. Carson, S. F. Ziegler, W. W. Kwok, and G. T. Nepom Functional avidity directs T-cell fate in autoreactive CD4+ T cells Blood, October 15, 2005; 106(8): 2798 - 2805. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Scotta, L. Tuosto, A. M. Masci, L. Racioppi, E. Piccolella, and L. Frasca Hypervariable region 1 variant acting as TCR antagonist affects hepatitis C virus-specific CD4+ T cell repertoire by favoring CD95-mediated apoptosis J. Leukoc. Biol., August 1, 2005; 78(2): 372 - 382. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Kriehuber, W. Bauer, A.-S. Charbonnier, D. Winter, S. Amatschek, D. Tamandl, N. Schweifer, G. Stingl, and D. Maurer Balance between NF-{kappa}B and JNK/AP-1 activity controls dendritic cell life and death Blood, July 1, 2005; 106(1): 175 - 183. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. S. Smith, T. Patterson, and M. E. Pauza Transgenic Ly-49A Inhibits Antigen-Driven T Cell Activation and Delays Diabetes J. Immunol., April 1, 2005; 174(7): 3897 - 3905. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Weiss, V. Donkova-Petrini, L. Caccavelli, M. Balbo, C. Carbonneil, and Y. Levy Human immunodeficiency virus-driven expansion of CD4+CD25+ regulatory T cells, which suppress HIV-specific CD4 T-cell responses in HIV-infected patients Blood, November 15, 2004; 104(10): 3249 - 3256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. H. Munn, M. D. Sharma, and A. L. Mellor Ligation of B7-1/B7-2 by Human CD4+ T Cells Triggers Indoleamine 2,3-Dioxygenase Activity in Dendritic Cells J. Immunol., April 1, 2004; 172(7): 4100 - 4110. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Guillot, S. Menoret, C. Guillonneau, C. Braudeau, M. G. Castro, P. Lowenstein, and I. Anegon Active suppression of allogeneic proliferative responses by dendritic cells after induction of long-term allograft survival by CTLA4Ig Blood, April 15, 2003; 101(8): 3325 - 3333. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W.-P. Min, D. Zhou, T. E. Ichim, G. H. Strejan, X. Xia, J. Yang, X. Huang, B. Garcia, D. White, P. Dutartre, et al. Inhibitory Feedback Loop Between Tolerogenic Dendritic Cells and Regulatory T Cells in Transplant Tolerance J. Immunol., February 1, 2003; 170(3): 1304 - 1312. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. James, D. Scott, J.-G. Chai, M. Millrain, P. Chandler, and E. Simpson HY peptides modulate transplantation responses to skin allografts Int. Immunol., November 1, 2002; 14(11): 1333 - 1342. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
