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 Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Andrásfalvy, M. Articles by Erdei, A. Search for Related Content PubMed PubMed Citation Articles by Andrásfalvy, M. Articles by Erdei, A.

The Subunit of the Type I Fc Receptor Is a Target for Peptides Inhibiting IgE-Mediated Secretory Response of Mast Cells¹

Márton Andrásfalvy^2,*, Hajna Péterfy^2,*, Gábor Tóth, János Matkó^*, Jakub Abramson^¶, Krisztina Kerekes^*, György Vámosi, Israel Pecht^¶ and Anna Erdei^3,*,

^* Department of Immunology and Immunology Research Group of the Hungarian Academy of Sciences at Eötvös Lorand University, Budapest, Hungary; Department of Medical Chemistry, University of Szeged, Szeged, Hungary; Cell Biophysics Research Group of Hungarian Academy of Sciences at University of Debrecen, Debrecen, Hungary; and ^¶ Department of Immunology, Weizmann Institute of Science, Rehovot, Israel

Peptides originally derived from complement component C3a were earlier shown to inhibit the type I FcR (FcRI)-mediated degranulation of mucosal type mast cells. In the present study, we show that C3a7, a peptide with a natural sequence, and its modified derivative, C3a9, are powerful inhibitors of the above response of both serosal and mucosal type mastocytes. We demonstrate that these peptides inhibit FcRI-induced membrane proximal events, suppress phosphorylation of the FcRI subunit, the protein tyrosine kinase Lyn, as well as the transient rise in free cytosolic Ca²⁺ level. The late phase of cellular response was also inhibited, as demonstrated by the reduced TNF- secretion. Experiments using two independent methods provided evidence that the interaction site of complement-derived peptides is the FcRI -chain. This was further supported by fluorescence confocal microscopic colocalization and resonance energy transfer measurements. Taken together, these results suggest the presence of distinct "activating" and "inhibitory" motifs in the C3a sequence. Response to both is in balance under physiologic conditions. Furthermore, present data predict that such inhibitory peptides may serve as potent agents for future therapeutic intervention.

This article has been cited by other articles:

				H. Peterfy, G. Toth, I. Pecht, and A. Erdei C3a-derived peptide binds to the type I Fc{varepsilon}R and inhibits proximal-coupling signal processes and cytokine secretion by mast cells Int. Immunol., July 24, 2008; (2008) dxn083v1. [Abstract] [Full Text] [PDF]