International Immunology, Vol. 11, No. 9, 1411-1422,
September 1999
© 1999 Japanese Society for Immunology
Defective TCR signaling events in glycosylphosphatidylinositol-deficient T cells derived from paroxysmal nocturnal hemoglobinuria patients
Institute of Biochemistry, BIL Biomedical Research Centre, University of Lausanne, 1066 Epalinges, Switzerland
Correspondence to: P. Romagnoli, U395 INSERM, BP 3028, 31024 Toulouse Cedex 3, France
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic disorder characterized by the presence of abnormal cells of various hematopoietic cell lineages deficient in surface expression of glycosylphosphatidylinositol (GPI)-anchored molecules. By analyzing T cells isolated from patients affected with PNH, it was found that ex vivo GPI-deficient CD4+ and CD8+ peripheral T cells display a more naive phenotype as compared to wild-type cells. In addition, in vitro proliferative responses to allogeneic antigen-presenting cells were shown to be reduced in mutant T cells. To investigate the molecular basis responsible for defective T cell activation in GPI-deficient T cells, T cell lines and T cell clones were generated from patients affected with PNH. When stimulated with anti-CD3
mAb, mutant cells displayed a significantly decreased activation of protein tyrosine kinase p56lck. The decreased kinase activity was accompanied by a delayed TCR capping and internalization. Interestingly, protein tyrosine phosphorylation is not only quantitatively but also qualitatively affected, with one substrate being more intensively phosphorylated in mutant than in wild-type cells. These observations suggest that a defective activation of p56lck contributes to the depressed immune responses observed in GPI-deficient T cells derived from PNH patients.
Keywords: glycosylphosphatidylinositol, paroxysmal nocturnal hemoglobinuria, TCR signaling
Transmitting editor: L. Moretta
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
G. Terrazzano, M. Sica, C. Becchimanzi, S. Costantini, B. Rotoli, S. Zappacosta, F. Alfinito, and G. Ruggiero T cells from paroxysmal nocturnal haemoglobinuria (PNH) patients show an altered CD40-dependent pathway J. Leukoc. Biol., July 1, 2005; 78(1): 27 - 36. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Staffler, A. Szekeres, G. J. Schutz, M. D. Saemann, E. Prager, M. Zeyda, K. Drbal, G. J. Zlabinger, T. M. Stulnig, and H. Stockinger Selective Inhibition of T Cell Activation Via CD147 Through Novel Modulation of Lipid Rafts J. Immunol., August 15, 2003; 171(4): 1707 - 1714. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Shichishima, M. Okamoto, K. Ikeda, T. Kaneshige, H. Sugiyama, T. Terasawa, K. Osumi, and Y. Maruyama HLA class II haplotype and quantitation of WT1 RNA in Japanese patients with paroxysmal nocturnal hemoglobinuria Blood, June 17, 2002; 100(1): 22 - 28. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-i. Nishimura, K. L. Phillips, R. E. Ware, S. Hall, L. Wilson, T. L. Gentry, T. A. Howard, Y. Murakami, M. Shibano, T. Machii, et al. Efficient retrovirus-mediated PIG-A gene transfer and stable restoration of GPI-anchored protein expression in cells with the PNH phenotype Blood, May 15, 2001; 97(10): 3004 - 3010. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Trotter, C. Klein, and E.-M. Kramer GPI-Anchored Proteins and Glycosphingolipid-Rich Rafts: Platforms for Adhesion and Signaling Neuroscientist, August 1, 2000; 6(4): 271 - 284. [Abstract] [PDF] |
||||



