Copyright © 2008 Kopetzki et al; licensee BioMed Central Ltd. Closing two doors of viral entry: Intramolecular combination of a coreceptor- and fusion inhibitor of HIV-1 Corresponding author. #Contributed equally. Erhard Kopetzki: erhard.kopetzki/at/roche.com; Andreas Jekle: andreas.jekle/at/roche.com; Changhua Ji: changhua.ji/at/roche.com; Eileen Rao: Eileen.rao/at/roche.com; Jun Zhang: jun.zhang/at/roche.com; Stephan Fischer: Stephan.fischer/at/roche.com; Nick Cammack: nick.cammack/at/roche.com; Surya Sankuratri: suryanarayna.sankuratri/at/roche.com; Gabrielle Heilek: gabrielle.heilek-snyder/at/roche.com Received March 25, 2008; Accepted May 1, 2008. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. | ||||
Abstract We describe a novel strategy in which two inhibitors of HIV viral entry were incorporated into a single molecule. This bifunctional fusion inhibitor consists of an antibody blocking the binding of HIV to its co-receptor CCR5, and a covalently linked peptide which blocks envelope mediated virus-cell fusion. This novel bifunctional molecule is highly active on CCR5- and X4-tropic viruses in a single cycle assay and a reporter cell line with IC50 values of 0.03–0.05 nM. We demonstrated that both inhibitors contribute to the antiviral activity. In the natural host peripheral blood mononuclear cells (PBMC) the inhibition of CXCR4-tropic viruses is dependant on the co-expression of CCR5 and CXCR4 receptors. This bifunctional inhibitor may offer potential for improved pharmacokinetic parameters for a fusion inhibitor in humans and the combination of two active antiviral agents in one molecule may provide better durability in controlling the emergence of resistant viruses. | ||||