Synthetic peptide conjugates with horseradish peroxidase and β-galactosidase for use in epitope-specific immunocytochemistry and ELISA

Jon D. Laman*, Alfons J.M. van den Eertwegh, Carla Deen, Nicole Vermeulen, Wim J.A. Boersma, Eric Claassen

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Synthetic peptide-alkaline phosphatase conjugates can be used to detect the epitope specificity of (i) antibody-forming cells in vivo by immunocytochemistry; (ii) of antibody secreting cells in vitro by spot-ELISA; and (iii) antibodies in solution by capture ELISA. The availability of synthetic peptide-enzyme conjugates using detector enzymes other than alkaline phosphatase would offer several important advantages, for example in double staining approaches. This paper reports the production of synthetic peptide-horseradish peroxidase conjugates and synthetic peptide-β-galactosidase conjugates. A peptide of 21 amino acids (SP 29) was coupled to peroxidase in seven differing molar ratios of peptide over peroxidase, ranging from 1:3.4 to 1:575, using periodate oxidation of the enzyme. SP 29 was coupled to β-galactosidase in four molar ratios ranging from 1.25 to 10, using glutaraldehyde pre-activation of the enzyme. The enzyme activity of the different conjugates was determined, the conjugates were tested in direct capture-ELISA with peptide-specific monoclonal antibodies, and the conjugates were tested in immunocytochemistry to detect peptide-specific B cells. The results show that the conjugates perform best if the peptide is coupled to the enzyme at relatively low molar ratios (1-30). The availability of these new peptide-enzyme conjugates broadens the applicability of synthetic peptides for detection purposes in several assay systems.

Original languageEnglish
Pages (from-to)1-10
Number of pages10
JournalJournal of Immunological Methods
Issue number1-2
Publication statusPublished - 15 Dec 1991

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