Article

The use of receptor-specific antibodies to study G-protein-coupled receptors.

Department of Pharmacology and Biological Chemistry, Box 1603, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029, USA.
Mount Sinai Journal of Medicine A Journal of Translational and Personalized Medicine (Impact Factor: 1.56). 08/2006; 73(4):673-81.
Source: PubMed

ABSTRACT The identification of G-protein-coupled receptor (GPCR) cDNAs has facilitated a number of studies characterizing the biochemical properties of the receptor protein. Most of these studies have used antibodies directed against the epitope-tagged receptor expressed in heterologous cells, because of the lack of sensitive and selective antibodies capable of recognizing endogenous receptors in their native state. In order to facilitate studies with endogenous receptors, efforts have been made to generate receptor-type selective, sensitive antibodies that are able to recognize endogenous receptors. In this review, we discuss the strategies as well as the details of the techniques used for the generation of monoclonal and polyclonal antibodies with a focus on family A GPCRs.

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    • "Due to the inherent problems in the production and purification of GPCRs, the use of the intact GPCR-proteins as antigen has been difficult. Hence, most antibodies recognizing GPCRs have so far been generated using synthetic peptide fragments of the receptor protein as antigens (Gupta and Devi, 2006; Mackrill, 2004). Zhang et al. (2004) further developed this strategy by synthetically producing cyclic peptides, thought to mimic the extracellular loops of the CCR5 receptor, for the selection of single-chain Fv (scFv) fragments. "
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    • "If these would be reliable, they would be highly important tools for pharmacological studies. Technical approaches for the generation and validation of receptor antibodies have been reviewed comprehensively (Gupta and Devi 2006; Mackrill 2004). Doubts about the usefulness of antibodies against GPCR (O'Connell et al. 2006; Pradidarcheep et al. 2008; Rhodes and Trimmer 2006), receptors from the ligand-gated ion channel family (Herber et al. 2004) or transmitter transporters (Chen et al. 2004) have been raised in the past and have even led to the retraction of papers (Hawes and Picciotto 2005). "
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