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) Submit an electronic Letter to the Editor about this paper Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science 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 ISI Web of Science (13) Citing Articles via Google Scholar Google Scholar Articles by Sompuram, S. R. Articles by Bogen, S. A. Search for Related Content PubMed PubMed Citation Articles by Sompuram, S. R. Articles by Bogen, S. A. Related Collections Clinical Immunology Molecular Diagnostics and Genetics Proteomics and Protein Markers Hematology Endocrinology and Metabolism

Synthetic Peptides Identified from Phage-displayed Combinatorial Libraries as Immunodiagnostic Assay Surrogate Quality-Control Targets

¹ CytoLogix Corporation, 99 Erie St., Cambridge, MA 02139.

² Holtherics Inc., 128 Spring St., Lexington, MA 02421.

³ Dyax Corporation, One Kendall Square, Cambridge, MA 02139.

^aAuthor for correspondence. Fax 617-576-0088; e-mail ssompuram{at}cytologix.com.

Background: Quantitative immunohistochemical (IHC) assays currently lack optimal reference quality-control material for cellular protein targets. To address this problem, we identified peptides that mimic the site on the native analyte to which the primary (monoclonal) antibody binds and used them as surrogate peptide controls.

Methods: We identified peptide candidates from a combinatorial peptide phage-display library that mimic the epitope for the 1D5 estrogen receptor (ER) monoclonal antibody (mAb). The peptide inserts of the phage clones were sequenced. Several phage-encoded peptides were then synthesized and analyzed for affinity and specificity.

Results: We identified phage clones that specifically bound to the ER 1D5 mAb. The binding was specific, in that the phage clones did not bind to two other isotype-matched mAbs. Their ability to bind the ER 1D5 mAb was related to the presence of a consensus sequence. Binding analysis revealed a K_d of 8.3 x 10^-8 mol/L. The peptide was not recognized by any of 15 other mAbs commonly used for clinical IHC testing. Moreover, the peptide was able to inhibit the binding of ER 1D5 mAb to native ER, indicating that the peptide bound to ER 1D5 mAb at or close to the antigen-binding site.

Conclusions: Surrogate peptide controls behave like the native analyte in terms of affinity and specificity. This technology may be especially useful when the native analyte is in short supply.

The following articles in journals at HighWire Press have cited this article:

				S. R. Sompuram, G. Bastas, K. Vani, and S. A. Bogen Accurate identification of paraprotein antigen targets by epitope reconstruction Blood, January 1, 2008; 111(1): 302 - 308. [Abstract] [Full Text] [PDF]

				S. R. Sompuram, V. Kodela, K. Zhang, H. Ramanathan, G. Radcliffe, P. Falb, and S. A. Bogen A Novel Quality Control Slide for Quantitative Immunohistochemistry Testing J. Histochem. Cytochem., November 1, 2002; 50(11): 1425 - 1434. [Abstract] [Full Text] [PDF]