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) Data Supplement 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 Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Huang, J. Articles by Zhu, C. Search for Related Content PubMed PubMed Citation Articles by Huang, J. Articles by Zhu, C.

Kinetics of MHC-CD8 Interaction at the T Cell Membrane¹

Jun Huang^*, Lindsay J. Edwards, Brian D. Evavold and Cheng Zhu^2,*,

^* Coulter Department of Biomedical Engineering, and Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332; and Department of Microbiology and Immunology, Emory University, Atlanta, GA 30322

CD8 plays an important role in facilitating TCR-MHC interaction, promoting Ag recognition, and initiating T cell activation. MHC-CD8 binding kinetics have been measured in three dimensions by surface plasmon resonance technique using purified molecules. However, CD8 is a membrane-anchored, signaling kinase-linked, and TCR-associated molecule whose function depends on the cell membrane environment. Purified molecules lack their linkage to the membrane, which precludes interactions with other structures of the cell as well as signaling. Furthermore, three-dimensional binding in the fluid phase is biologically and physically distinct from two-dimensional binding across apposing cell membranes. As a first step toward characterizing the molecular interactions between T cells and APCs, we used a micropipette adhesion frequency assay to measure the adhesion kinetics of single mouse T cells interacting with single human RBCs coated with MHC. Using anti-TCR mAb we isolated and characterized the specific two-dimensional MHC-CD8 binding from the trimolecular TCR-MHC-CD8 interaction. The TCR-independent MHC-CD8 interaction has a very low affinity that depends on the MHC alleles, but not on the peptide complexed to the MHC and whether CD8 is an homodimer or an β heterodimer. Surprisingly, MHC-CD8 binding affinity varies with T cells from different TCR transgenic mice and these affinity differences were abolished by treatment with cholesterol oxidase to disrupt membrane rafts. These data highlight the relevance and importance of two-dimensional analysis of T cells and APCs and indicate that membrane rafts play an important role in modulating the affinity of cell-cell interactions.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ This work was supported by National Institutes of Health Grants AI38282 (to C.Z.) and AI56017 (to B.D.E.).

² Address correspondence and reprint requests to Dr. Cheng Zhu, Coulter Department of Biomedical Engineering, Georgia Institute of Technology, 315 Ferst Drive, Atlanta, GA 30332. E-mail address: cheng.zhu{at}bme.gatech.edu

³ Abbreviations used in this paper: Lck, Src kinase p56^lck; EAS45, experimental additive solutions 45; pMHC, peptide MHC; SPR, surface plasmon resonance; 2D, two dimension(al); 3D, three dimension(al).

⁴ The online version of this article contains supplemental material.

This article has been cited by other articles:

				M. L. Dustin Visualizing Immune System Complexity Sci. Signal., April 14, 2009; 2(66): mr4 - mr4. [Abstract] [Full Text] [PDF]

				H. A. Wasserman, C. D. Beal, Y. Zhang, N. Jiang, C. Zhu, and B. D. Evavold MHC Variant Peptide-Mediated Anergy of Encephalitogenic T Cells Requires SHP-1 J. Immunol., November 15, 2008; 181(10): 6843 - 6849. [Abstract] [Full Text] [PDF]

				D. S. Jones, P. Reichardt, M. L. Ford, L. J. Edwards, and B. D. Evavold TCR Antagonism by Peptide Requires High TCR Expression J. Immunol., August 1, 2008; 181(3): 1760 - 1766. [Abstract] [Full Text] [PDF]

				M. Mallaun, D. Naeher, M. A. Daniels, P. P. Yachi, B. Hausmann, I. F. Luescher, N. R. J. Gascoigne, and E. Palmer The T Cell Receptor's {alpha}-Chain Connecting Peptide Motif Promotes Close Approximation of the CD8 Coreceptor Allowing Efficient Signal Initiation J. Immunol., June 15, 2008; 180(12): 8211 - 8221. [Abstract] [Full Text] [PDF]

				Y.-H. Chien, N. Jiang, F. Li, F. Zhang, C. Zhu, and D. Leckband Two Stage Cadherin Kinetics Require Multiple Extracellular Domains but Not the Cytoplasmic Region J. Biol. Chem., January 25, 2008; 283(4): 1848 - 1856. [Abstract] [Full Text] [PDF]