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 Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kilmon, M. A. Articles by Conrad, D. H. Search for Related Content PubMed PubMed Citation Articles by Kilmon, M. A. Articles by Conrad, D. H.

Regulation of IgE Production Requires Oligomerization of CD23¹

Michelle A. Kilmon^2,*, Rodolfo Ghirlando^3,, Marie-Paule Strub^4,, Rebecca L. Beavil, Hannah J. Gould and Daniel H. Conrad^*

^* Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298; Faculté de Pharmacie, Centre de Biochimie Structurale, Institut National de la Santé et de la Recherche Médicale Unité 414, Montpellier, France; and The Randall Centre for Molecular Mechanisms of Cell Function, King’s College London, London, United Kingdom

Here we describe the production of a rabbit polyclonal Ab (RAS1) raised against the stalk of murine CD23. RAS1 inhibits release of CD23 from the surface of both M12 and B cells resulting in an increase of CD23 on the cell surface. Despite this increase, these cells are unable to bind IgE as determined by FACS. CD23 has previously been shown to bind IgE with both a high (4–10 x 10⁷ M^-1) and low (4–10 x 10⁶ M^-1) affinity. Closer examination by direct binding of ¹²⁵I-IgE revealed that RAS1 blocks high affinity binding while having no effect on low affinity binding. These data support the model proposing that oligomers of CD23 mediate high affinity IgE binding. These experiments suggest that RAS1 binding to cell surface CD23 results in a shift from oligomers to monomers, which, according to the model, only bind IgE with low affinity. These experiments also suggest that high affinity binding of IgE is required for IgE regulation by CD23 and is demonstrated by the fact that treatment of Ag/Alum-immunized mice treated with RAS1 results in a significant increase in IgE production similar to the levels seen in CD23-deficient mice. These mice also had significantly decreased levels of serum soluble CD23 and Ag-specific IgG1. RAS1 had no effect on IgE or Ag-specific IgG1 production in CD23-deficient mice.

This article has been cited by other articles:

				G. A. Lemieux, F. Blumenkron, N. Yeung, P. Zhou, J. Williams, A. C. Grammer, R. Petrovich, P. E. Lipsky, M. L. Moss, and Z. Werb The Low Affinity IgE Receptor (CD23) Is Cleaved by the Metalloproteinase ADAM10 J. Biol. Chem., May 18, 2007; 282(20): 14836 - 14844. [Abstract] [Full Text] [PDF]

				I. Sayers, J. E. M. Housden, A. C. Spivey, and B. A. Helm The Importance of Lys-352 of Human Immunoglobulin E in Fc{epsilon}RII/CD23 Recognition J. Biol. Chem., August 20, 2004; 279(34): 35320 - 35325. [Abstract] [Full Text] [PDF]

				M. A. Kilmon, A. E. Shelburne, Y. Chan-Li, K. L. Holmes, and D. H. Conrad CD23 Trimers Are Preassociated on the Cell Surface Even in the Absence of Its Ligand, IgE J. Immunol., January 15, 2004; 172(2): 1065 - 1073. [Abstract] [Full Text] [PDF]