Antibody degradation in tobacco plants: a predominantly apoplastic process

BMC Biotechnology

Research Article

Matthew J Paul¹  Julian KC Ma¹  Pascal M Drake¹  Verena K Hehle¹  Craig J van Dolleweerd¹ 

[1] Molecular Immunology Unit, Division of Clinical Sciences, St George's, University of London, SW17 0RE, Cranmer Terrace, London, UK;

关键词: Proteolytic Degradation;    Free Light Chain;    Apoplastic Space;    Lower Molecular Weight Species;    Tabacum Plant;   

DOI  :  10.1186/1472-6750-11-128

 received in 2011-04-07, accepted in 2011-12-30,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundInterest in using plants for production of recombinant proteins such as monoclonal antibodies is growing, but proteolytic degradation, leading to a loss of functionality and complications in downstream purification, is still a serious problem.ResultsIn this study, we investigated the dynamics of the assembly and breakdown of a human IgG1κ antibody expressed in plants. Initial studies in a human IgG transgenic plant line suggested that IgG fragments were present prior to extraction. Indeed, when the proteolytic activity of non-transgenic Nicotiana tabacum leaf extracts was tested against a human IgG1 substrate, little activity was detectable in extraction buffers with pH > 5. Significant degradation was only observed when the plant extract was buffered below pH 5, but this proteolysis could be abrogated by addition of protease inhibitors. Pulse-chase analysis of IgG MAb transgenic plants also demonstrated that IgG assembly intermediates are present intracellularly and are not secreted, and indicates that the majority of proteolytic degradation occurs following secretion into the apoplastic space.ConclusionsThe results provide evidence that proteolytic fragments derived from antibodies of the IgG subtype expressed in tobacco plants do not accumulate within the cell, and are instead likely to occur in the apoplastic space. Furthermore, any proteolytic activity due to the release of proteases from subcellular compartments during tissue disruption and extraction is not a major consideration under most commonly used extraction conditions.

【 授权许可】

Unknown   
© Hehle et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. 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.