Published online before print May 10, 2004

This Article Full Text Full Text (PDF) All Versions of this Article: jlb.1103562v1 76/2/491    most recent Alert me when this article is cited Alert me if a correction is posted 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 Huang, Z.-Y. Articles by Schreiber, A. D. Search for Related Content PubMed PubMed Citation Articles by Huang, Z.-Y. Articles by Schreiber, A. D.

(Journal of Leukocyte Biology. 2004;76:491-499.)
© 2004 by Society for Leukocyte Biology

The monocyte Fc receptors FcRI/ and FcRIIA differ in their interaction with Syk and with Src-related tyrosine kinases

University of Pennsylvania School of Medicine, Hematology and Oncology Division, Philadelphia

¹Correspondence: University of Pennsylvania School of Medicine, Hematology and Oncology Division, Biomedical Research Building II/III, Room 705, 421 Curie Blvd., Philadelphia, PA 19104. E-mail: schreibr{at}mail.med.upenn.edu

There are important differences in signaling between the Fc receptor for immunoglobulin G (IgG) FcRIIA, which uses the Ig tyrosine-activating motif (ITAM) within its own cytoplasmic domain, and FcRI, which transmits signals by means of an ITAM located within the cytoplasmic domain of its associated -chain. For example, in transfected epithelial cells and COS-1 cells, FcRIIA mediates phagocytosis of IgG-coated red blood cells more efficiently than does FcRI/, and enhancement of phagocytosis by Syk kinase is more pronounced for FcRI/ than for FcRIIA. In addition, structure/function studies indicate that the -chain ITAM and the FcRIIA ITAM have different requirements for mediating the phagocytic signal. To study the differences between FcRIIA and FcRI/, we examined the interaction of FcRIIA and the FcRI/ chimera FcRI-- (extracellular domain–transmembrane domain–cytoplasmic domain) with Syk kinase and with the Src-related tyrosine kinases (SRTKs) Hck and Lyn in transfected COS-1 cells. Our data indicate that FcRIIA interacts more readily with Syk than does FcRI-- and suggest that one consequence may be the greater phagocytic efficiency of FcRIIA compared with FcRI/. Furthermore, individual SRTKs affect the efficiency of phagocytosis differently for FcRI-- and FcRIIA and also influence the ability of these receptors to interact with Syk kinase. Taken together, the data suggest that differences in signaling by FcRIIA and FcRI-- are related in part to interaction with Syk and Src kinases and that individual SRTKs play different roles in FcR-mediated phagocytosis.

Key Words: ITAM • phagocytosis • Hck

This article has been cited by other articles:

				R. M. Gilberti, G. N. Joshi, and D. A. Knecht The Phagocytosis of Crystalline Silica Particles by Macrophages Am. J. Respir. Cell Mol. Biol., November 1, 2008; 39(5): 619 - 627. [Abstract] [Full Text] [PDF]

				Z.-Y. Huang, D. R. Barreda, R. G. Worth, Z. K. Indik, M.-K. Kim, P. Chien, and A. D. Schreiber Differential kinase requirements in human and mouse Fc-gamma receptor phagocytosis and endocytosis J. Leukoc. Biol., December 1, 2006; 80(6): 1553 - 1562. [Abstract] [Full Text] [PDF]

				D. Pilling, N. M. Tucker, and R. H. Gomer Aggregated IgG inhibits the differentiation of human fibrocytes J. Leukoc. Biol., June 1, 2006; 79(6): 1242 - 1251. [Abstract] [Full Text] [PDF]

				C. Cougoule, S. Hoshino, A. Dart, J. Lim, and E. Caron Dissociation of Recruitment and Activation of the Small G-protein Rac during Fc{gamma} Receptor-mediated Phagocytosis J. Biol. Chem., March 31, 2006; 281(13): 8756 - 8764. [Abstract] [Full Text] [PDF]