AGEM400(HES), a Novel Erythropoietin Mimetic Peptide Conjugated to Hydroxyethyl Starch with Excellent In Vitro Efficacy
Alexandra Greindl, Claudia Kessler, Bettina Breuer, Udo Haber, Andreas Rybka, Marco Emgenbroich, Andy J.G. Pötgens*, Hans-Georg Frank
Identifiers and Pagination:Year: 2010
First Page: 1
Last Page: 14
Publisher Id: TOHJ-4-1
Article History:Received Date: 06/07/2010
Revision Received Date: 20/07/2010
Acceptance Date: 22/07/2010
Electronic publication date: 15/9/2010
Collection year: 2010
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
We developed and tested a compound called AGEM400(HES) that consists of a novel erythropoietin mimetic peptide (EMP) which is produced as a continuous N- to C-linked dimer and is conjugated to biodegradable hydroxyethyl starch (HES). In various in vitro assays, AGEM400(HES) demonstrated excellent efficacy, better than the peptide alone, and comparable to the efficacy of erythropoietin (EPO) and Aranesp (Darbepoietin alpha). The assays included survival assays on EPO-responsive cell lines (EC50 below 1 ng/ml peptide) and clonogenic assays on human bone marrow cells (EC50 1 to 10 ng/ml). AGEM400(HES) caused phosphorylation of STAT5 and ERK signalling proteins in UT7/EPO cells in a similar fashion as EPO. AGEM400(HES) replaced EPO from its receptor and the in vitro activity of AGEM400 (HES) was inhibited by soluble EPO receptor. Antibodies generated in mice and rabbits against EPO did not recognize AGEM400(HES) peptide, and vice versa. A sensitive ELISA was able to detect AGEM400(HES) at low nanogram per ml concentrations which allows for bioanalytics of AGEM400(HES) serum levels in future in vivo studies. As a result, AGEM400(HES) is a promising drug candidate for anemias related to renal insufficiency and/or in oncological settings.