| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Institut de Génétique Moléculaire de Montpellier, Centre National de la Recherche Scientifique Unité Mixte de Recherche 5535/Institut Fédératif de Recherche 122, Montpellier, France
Cytokines play a crucial role in the maintenance of polyclonal naive and memory T cell populations. It has previously been shown that ex vivo, the IL-7 cytokine induces the proliferation of naive recent thymic emigrants (RTE) isolated from umbilical cord blood but not mature adult-derived naive and memory human CD4+ T cells. We find that the combination of IL-2 and IL-7 strongly promotes the proliferation of RTE, whereas adult CD4+ T cells remain relatively unresponsive. Immunological activity is controlled by a balance between proliferation and apoptotic cell death. However, the relative contributions of IL-2 and IL-7 in regulating these processes in the absence of MHC/peptide signals are not known. Following exposure to either IL-2 or IL-7 alone, RTE, as well as mature naive and memory CD4+ T cells, are rendered only minimally sensitive to Fas-mediated cell death. However, in the presence of the two cytokines, Fas engagement results in a high level of caspase-dependent apoptosis in both RTE as well as naive adult CD4+ T cells. In contrast, equivalently treated memory CD4+ T cells are significantly less sensitive to Fas-induced cell death. The increased susceptibility of RTE and naive CD4+ T cells to Fas-induced apoptosis correlates with a significantly higher IL-2/IL-7-induced Fas expression on these T cell subsets than on memory CD4+ T cells. Thus, IL-2 and IL-7 regulate homeostasis by modulating the equilibrium between proliferation and apoptotic cell death in RTE and mature naive and memory T cell subsets.
Related articles in The JI:
This article has been cited by other articles:
|
|
 |
|
  Z. Wang, C. Zhao, R. Moya, and J. D. Davies A Novel Role for CD4+ T Cells in the Control of Cachexia J. Immunol., October 1, 2008; 181(7): 4676 - 4684. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Rethi, N. Vivar, S. Sammicheli, C. Fluur, N. Ruffin, A. Atlas, E. Rajnavolgyi, and F. Chiodi Priming of T cells to Fas-mediated proliferative signals by interleukin-7 Blood, August 15, 2008; 112(4): 1195 - 1204. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. V. Dolfi, A. C. Boesteanu, C. Petrovas, D. Xia, E. A. Butz, and P. D. Katsikis Late Signals from CD27 Prevent Fas-Dependent Apoptosis of Primary CD8+ T Cells J. Immunol., March 1, 2008; 180(5): 2912 - 2921. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Fluur, A. De Milito, T. J. Fry, N. Vivar, L. Eidsmo, A. Atlas, C. Federici, P. Matarrese, M. Logozzi, E. Rajnavolgyi, et al. Potential Role for IL-7 in Fas-Mediated T Cell Apoptosis During HIV Infection J. Immunol., April 15, 2007; 178(8): 5340 - 5350. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Swainson, S. Kinet, C. Mongellaz, M. Sourisseau, T. Henriques, and N. Taylor IL-7-induced proliferation of recent thymic emigrants requires activation of the PI3K pathway Blood, February 1, 2007; 109(3): 1034 - 1042. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Swainson, E. Verhoeyen, F.-L. Cosset, and N. Taylor IL-7R{alpha} Gene Expression Is Inversely Correlated with Cell Cycle Progression in IL-7-Stimulated T Lymphocytes. J. Immunol., June 1, 2006; 176(11): 6702 - 6708. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. R. Ryan, R. Shepherd, J. K. Leavey, Y. Gao, F. Grassi, F. J. Schnell, W.-P. Qian, G. J. Kersh, M. N. Weitzmann, and R. Pacifici An IL-7-dependent rebound in thymic T cell output contributes to the bone loss induced by estrogen deficiency PNAS, November 15, 2005; 102(46): 16735 - 16740. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Baratelli, Y. Lin, L. Zhu, S.-C. Yang, N. Heuze-Vourc'h, G. Zeng, K. Reckamp, M. Dohadwala, S. Sharma, and S. M. Dubinett Prostaglandin E2 Induces FOXP3 Gene Expression and T Regulatory Cell Function in Human CD4+ T Cells J. Immunol., August 1, 2005; 175(3): 1483 - 1490. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. Rochman, W. E. Paul, and S. Z. Ben-Sasson IL-6 Increases Primed Cell Expansion and Survival J. Immunol., April 15, 2005; 174(8): 4761 - 4767. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.-D. Lelievre, F. Petit, D. Arnoult, J.-C. Ameisen, and J. Estaquier Interleukin 7 Increases Human Immunodeficiency Virus Type 1 LAI-Mediated Fas-Induced T-Cell Death J. Virol., March 1, 2005; 79(5): 3195 - 3199. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Dondi, G. Roue, V. J. Yuste, S. A. Susin, and S. Pellegrini A Dual Role of IFN-{alpha} in the Balance between Proliferation and Death of Human CD4+ T Lymphocytes during Primary Response J. Immunol., September 15, 2004; 173(6): 3740 - 3747. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
