Gueorguieva, D. et al. Identification of single domain, Bax-specific intrabodies that confer resistance to mammalian cells against oxidative-stress-induced apoptosis. FASEB. J. 20, 2636-2638

Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario, Canada
The FASEB Journal (Impact Factor: 5.04). 01/2007; 20(14):2636-8. DOI: 10.1096/fj.06-6306fje
Source: PubMed


Bax is a proapoptotic protein implicated in cell death involved in several neurodegenerative diseases. Intracellularly expressed antibody (Ab) fragments (intrabodies) inhibiting Bax function would have potential for developing therapeutics for the aforementioned diseases and can serve as research tools. We report identification, cloning, and functional characterization of several Bax-specific single-domain antibodies (sdAbs). These minimal size Ab fragments, which were isolated from a llama V(H)H phage display library by panning, inhibited Bax function in in vitro assays. Importantly, as intrabodies, these sdAbs, which were stably expressed in mammalian cells, were nontoxic to their host cells and rendered them highly resistant to oxidative-stress-induced apoptosis. The intrabodies prevented mitochondrial membrane potential collapse and apoptosis after oxidative stress in the host cells. These anti-Bax V(H)Hs could be used as tools for studying the role of Bax in oxidative-stress-induced apoptosis and for developing novel therapeutics for the degenerative diseases involving oxidative stress.

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Available from: Siyaram Pandey, Dec 17, 2013
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    • "The stability of Nbs is perfectly suited for the production of intrabodies that require their expression in the reducing environment of the cytoplasm. Bax-specific intrabodies have been developed to prevent the oxidative stress-induced apoptosis that is implicated in neurodegenerative diseases.44 The targeting of intracellular proteins may also proceed with the fusion of Nbs to peptides, thus mediating translocation across the cell membrane – although intrachain disulfide bonding could hamper unfolding and translocation. "
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    • "In fact, their high intrinsic stability allows them to fold properly in reducing environments that do not allow disulfide bond formation such as cell cytoplasm or nucleus. Consequently, and unlike conventional antibody fragments, most sdAbs can efficiently be used as intracellular antibodies (intrabodies) to probe or block a specific epitope of an intracellular protein (Muyldermans 2001; Gueorguieva et al. 2006; Rothbauer et al. 2006; Verheesen et al. 2006; Groot et al. 2008; Serruys et al. 2009). Last but not least, the genes of these fragments show a large degree of homology with the VH3 subset of human VH genes (Ewert et al. 2002; Su et al. 2002), which confer them a low antigenicity in humans, a very attractive feature for immunotherapy approaches. "
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