HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Brooke, G. Articles by Barclay, A. N. Search for Related Content PubMed PubMed Citation Articles by Brooke, G. Articles by Barclay, A. N.

Human Lymphocytes Interact Directly with CD47 through a Novel Member of the Signal Regulatory Protein (SIRP) Family¹

Gary Brooke^*, Joanna D. Holbrook, Marion H. Brown^* and A. Neil Barclay^2,*

^* Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom; and GlaxoSmithKline UK Ltd., Uxbridge, United Kingdom

Two closely related proteins, signal regulatory protein (SIRP; SHPS-1/CD172) and SIRP, have been described in humans. The existence of a third SIRP protein has been suggested by cDNA sequence only. We show that this third SIRP is a separate gene that is expressed as a protein with unique characteristics from both and genes and suggest that this gene should be termed SIRP. We have expressed the extracellular region of SIRP as a soluble protein and have shown that, like SIRP, it binds CD47, but with a lower affinity (K_d, 23 µM) compared with SIRP (K_d, 2 µM). mAbs specific to SIRP show that it was not expressed on myeloid cells, in contrast to SIRP and -, being expressed instead on the majority of T cells and a proportion of B cells. The short cytoplasmic tail of SIRP does not contain any known signaling motifs, nor does it contain a characteristic lysine, as with SIRP, that is required for DAP12 interaction. DAP12 coexpression is a requirement for SIRP surface expression, whereas SIRP is expressed in its absence. The SIRP-CD47 interaction may therefore not be capable of bidirectional signaling as with the SIRP-CD47, but, instead, use unidirectional signaling via CD47 only.

This article has been cited by other articles:

				M. Stefanidakis, G. Newton, W. Y. Lee, C. A. Parkos, and F. W. Luscinskas Endothelial CD47 interaction with SIRP{gamma} is required for human T-cell transendothelial migration under shear flow conditions in vitro Blood, August 15, 2008; 112(4): 1280 - 1289. [Abstract] [Full Text] [PDF]

				D. Hatherley, K. Harlos, D. C. Dunlop, D. I. Stuart, and A. N. Barclay The Structure of the Macrophage Signal Regulatory Protein {alpha} (SIRP{alpha}) Inhibitory Receptor Reveals a Binding Face Reminiscent of That Used by T Cell Receptors J. Biol. Chem., May 11, 2007; 282(19): 14567 - 14575. [Abstract] [Full Text] [PDF]

				S. Subramanian, E. T. Boder, and D. E. Discher Phylogenetic Divergence of CD47 Interactions with Human Signal Regulatory Protein {alpha} Reveals Locus of Species Specificity: IMPLICATIONS FOR THE BINDING SITE J. Biol. Chem., January 19, 2007; 282(3): 1805 - 1818. [Abstract] [Full Text] [PDF]

				D. Braun, L. Galibert, T. Nakajima, H. Saito, V. V. Quang, M. Rubio, and M. Sarfati Semimature Stage: A Checkpoint in a Dendritic Cell Maturation Program That Allows for Functional Reversion after Signal-Regulatory Protein-{alpha} Ligation and Maturation Signals J. Immunol., December 15, 2006; 177(12): 8550 - 8559. [Abstract] [Full Text] [PDF]

				M. H. Lahoud, A. I. Proietto, K. H. Gartlan, S. Kitsoulis, J. Curtis, J. Wettenhall, M. Sofi, C. Daunt, M. O'Keeffe, I. Caminschi, et al. Signal Regulatory Protein Molecules Are Differentially Expressed by CD8- Dendritic Cells J. Immunol., July 1, 2006; 177(1): 372 - 382. [Abstract] [Full Text] [PDF]

				E. M. van Beek, F. Cochrane, A. N. Barclay, and T. K. van den Berg Signal Regulatory Proteins in the Immune System J. Immunol., December 15, 2005; 175(12): 7781 - 7787. [Abstract] [Full Text] [PDF]

				Y. Liu, I. Soto, Q. Tong, A. Chin, H.-J. Buhring, T. Wu, K. Zen, and C. A. Parkos SIRP{beta}1 Is Expressed as a Disulfide-linked Homodimer in Leukocytes and Positively Regulates Neutrophil Transepithelial Migration J. Biol. Chem., October 28, 2005; 280(43): 36132 - 36140. [Abstract] [Full Text] [PDF]

				J. Alblas, H. Honing, C. Renardel de Lavalette, M. H. Brown, C. D. Dijkstra, and T. K. van den Berg Signal Regulatory Protein {alpha} Ligation Induces Macrophage Nitric Oxide Production through JAK/STAT- and Phosphatidylinositol 3-Kinase/Rac1/NAPDH Oxidase/H2O2-Dependent Pathways Mol. Cell. Biol., August 15, 2005; 25(16): 7181 - 7192. [Abstract] [Full Text] [PDF]

				D. Hatherley, H. M. Cherwinski, M. Moshref, and A. N. Barclay Recombinant CD200 Protein Does Not Bind Activating Proteins Closely Related to CD200 Receptor J. Immunol., August 15, 2005; 175(4): 2469 - 2474. [Abstract] [Full Text] [PDF]

				P.-A. Oldenborg CD47 and SIRPs: new openings Blood, March 15, 2005; 105(6): 2245 - 2246. [Full Text] [PDF]