| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
,
* Institut National de la Recherche Agronomique, Unité de Virologie et Immunologie Moléculaires, Jouy-en-Josas, France;
Western Fisheries Research Center, U.S. Geological Survey’s Biological Resources Division, Seattle, WA 98115;
Department of Pathobiology, University of Washington, Seattle, WA 98686;
School of Biological Sciences, Washington State University, Vancouver, WA 99164; and
¶
Unité d’Immunologie Moléculaire, Institut Pasteur, Paris, France
T cell activation requires both specific recognition of the peptide-MHC complex by the TCR and additional signals delivered by costimulatory receptors. We have identified rainbow trout sequences similar to CD28 (rbtCD28) and CTLA4 (rbtCTLA4). rbtCD28 and rbtCTLA4 are composed of an extracellular Ig-superfamily V domain, a transmembrane region, and a cytoplasmic tail. The presence of a conserved ligand binding site within the V domain of both molecules suggests that these receptors likely recognize the fish homologues of the B7 family. The mRNA expression pattern of rbtCD28 and rbtCTLA4 in naive trout is reminiscent to that reported in humans and mice, because rbtCTLA4 expression within trout leukocytes was quickly up-regulated following PHA stimulation and virus infection. The cytoplasmic tail of rbtCD28 possesses a typical motif that is conserved in mammalian costimulatory receptors for signaling purposes. A chimeric receptor made of the extracellular domain of human CD28 fused to the cytoplasmic tail of rbtCD28 promoted TCR-induced IL-2 production in a human T cell line, indicating that rbtCD28 is indeed a positive costimulator. The cytoplasmic tail of rbtCTLA4 lacked obvious signaling motifs and accordingly failed to signal when fused to the huCD28 extracellular domain. Interestingly, rbtCTLA4 and rbtCD28 are not positioned on the same chromosome and thus do not belong to a unique costimulatory cluster as in mammals. Finally, our results raise questions about the origin and evolution of positive and negative costimulation in vertebrate immune systems.
This article has been cited by other articles:
|
|
 |
|
  Y.-A. Zhang, J.-i. Hikima, J. Li, S. E. LaPatra, Y.-P. Luo, and J. O. Sunyer Conservation of Structural and Functional Features in a Primordial CD80/86 Molecule from Rainbow Trout (Oncorhynchus mykiss), a Primitive Teleost Fish J. Immunol., July 1, 2009; 183(1): 83 - 96. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Khoufache, F. LeBouder, E. Morello, F. Laurent, S. Riffault, P. Andrade-Gordon, S. Boullier, P. Rousset, N. Vergnolle, and B. Riteau Protective Role for Protease-Activated Receptor-2 against Influenza Virus Pathogenesis via an IFN-{gamma}-Dependent Pathway J. Immunol., June 15, 2009; 182(12): 7795 - 7802. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Sugamata, H. Suetake, K. Kikuchi, and Y. Suzuki Teleost B7 Expressed on Monocytes Regulates T Cell Responses J. Immunol., June 1, 2009; 182(11): 6799 - 6806. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. LeBouder, E. Morello, G. F. Rimmelzwaan, F. Bosse, C. Pechoux, B. Delmas, and B. Riteau Annexin II Incorporated into Influenza Virus Particles Supports Virus Replication by Converting Plasminogen into Plasmin J. Virol., July 15, 2008; 82(14): 6820 - 6828. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
