SEARCH:   Advanced

Blood, 15 December 2006, Vol. 108, No. 13, pp. 4094-4101. Prepublished online as a Blood First Edition Paper on August 15, 2006; DOI 10.1182/blood-2006-03-011742. This Article Full Text Full Text (PDF) All Versions of this Article: blood-2006-03-011742v1 108/13/4094    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Rights and Permissions Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Fischer, K. Articles by Mackensen, A. Search for Related Content PubMed PubMed Citation Articles by Fischer, K. Articles by Mackensen, A. Related Collections Immunobiology Signal Transduction Social Bookmarking                   What's this?  Previous Article  |  Table of Contents  |  Next Article  IMMUNOBIOLOGY Antigen recognition induces phosphatidylserine exposure on the cell surface of human CD8+ T cells Karin Fischer, Simon Voelkl, Jana Berger, Reinhard Andreesen, Thomas Pomorski, and Andreas Mackensen From the Department of Hematology and Oncology, University of Regensburg, Regensburg, Germany; and Institute of Biology, Cell Biophysics, Humboldt University Berlin, Berlin, Germany. In eukaryotic cells the phospholipid phosphatidylserine (PS) is restricted to the inner plasma-membrane leaflet. This lipid asymmetry, which is maintained by the concerted action of phospholipid transport proteins, is mainly lost during apoptosis. Here, we demonstrate that primary human CD8+ cytotoxic T lymphocytes (CTLs) expose PS on T-cell receptor (TCR)–mediated antigen (Ag) recognition. In contrast to PS externalization on apoptotic cells, activation-induced PS exposure is less pronounced and reversible. Fluorescence microscopic analysis revealed that PS is distributed nonhomogenously over the plasma membrane and concentrated in membrane lipid raft domains at the immunologic synapse. By studying the activity of PS transport proteins using a fluorescence-labeled PS analogue, we found that activation of CTLs inhibited the flippase-mediated inward-directed PS transport without affecting the outward transport. Shielding of exposed PS by annexin V protein during Ag recognition diminished cytokine secretion, activation, and cell-to-cell clustering of Ag-specific CTLs. In summary, our data demonstrate for the first time that externalized PS on Ag-stimulated CTLs is linked to T-cell activation and probably involved in cell-to-cell contact formation at the immunologic synapse. CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this? This article has been cited by other articles: S. R. Stowell, S. Karmakar, C. M. Arthur, T. Ju, L. C. Rodrigues, T. B. Riul, M. Dias-Baruffi, J. Miner, R. P. McEver, and R. D. Cummings Galectin-1 Induces Reversible Phosphatidylserine Exposure at the Plasma Membrane Mol. Biol. Cell, March 1, 2009; 20(5): 1408 - 1418. [Abstract] [Full Text] [PDF] F. G. Blankenberg In Vivo Detection of Apoptosis J. Nucl. Med., June 1, 2008; 49(Suppl_2): 81S - 95S. [Abstract] [Full Text] [PDF] D. Smrz, P. Lebduska, L. Draberova, J. Korb, and P. Draber Engagement of Phospholipid Scramblase 1 in Activated Cells: IMPLICATION FOR PHOSPHATIDYLSERINE EXTERNALIZATION AND EXOCYTOSIS J. Biol. Chem., April 18, 2008; 283(16): 10904 - 10918. [Abstract] [Full Text] [PDF] C. Schutz, M. Fleck, A. Mackensen, A. Zoso, D. Halbritter, J. P. Schneck, and M. Oelke Killer artificial antigen-presenting cells: a novel strategy to delete specific T cells Blood, April 1, 2008; 111(7): 3546 - 3552. [Abstract] [Full Text] [PDF] S. R. Stowell, Y. Qian, S. Karmakar, N. S. Koyama, M. Dias-Baruffi, H. Leffler, R. P. McEver, and R. D. Cummings Differential Roles of Galectin-1 and Galectin-3 in Regulating Leukocyte Viability and Cytokine Secretion J. Immunol., March 1, 2008; 180(5): 3091 - 3102. [Abstract] [Full Text] [PDF] A. E. Schade, G. L. Schieven, R. Townsend, A. M. Jankowska, V. Susulic, R. Zhang, H. Szpurka, and J. P. Maciejewski Dasatinib, a small-molecule protein tyrosine kinase inhibitor, inhibits T-cell activation and proliferation Blood, February 1, 2008; 111(3): 1366 - 1377. [Abstract] [Full Text] [PDF] D. Smrz, L. Draberova, and P. Draber Non-apoptotic Phosphatidylserine Externalization Induced by Engagement of Glycosylphosphatidylinositol-anchored Proteins J. Biol. Chem., April 6, 2007; 282(14): 10487 - 10497. [Abstract] [Full Text] [PDF] Y. Y. Tyurina, L. V. Basova, N. V. Konduru, V. A. Tyurin, A. I. Potapovich, P. Cai, H. Bayir, D. Stoyanovsky, B. R. Pitt, A. A. Shvedova, et al. Nitrosative Stress Inhibits the Aminophospholipid Translocase Resulting in Phosphatidylserine Externalization and Macrophage Engulfment: IMPLICATIONS FOR THE RESOLUTION OF INFLAMMATION J. Biol. Chem., March 16, 2007; 282(11): 8498 - 8509. [Abstract] [Full Text] [PDF]

	Copyright © 2006 by American Society of Hematology         Online ISSN: 1528-0020