A Nanostructured Bacterial Bioscaffold for The Sustained Bottom-Up Delivery of Protein Drugs

Abstract

Aims: Bacterial inclusion bodies (IBs) are protein-based, amyloidal nanomaterials that mechanically stimulate mammalian cell proliferation upon surface decoration. However, their biological performance as potentially functional scaffolds in mammalian cell culture still needs to be explored. Materials & methods: Using fluorescent proteins, we demonstrate significant membrane penetration of surface-attached IBs and a corresponding intracellular bioavailability of the protein material. Results: When IBs are formed by protein drugs, such as the intracellular acting human chaperone Hsp70 or the extracellular/intracellular acting human FGF-2, IB components intervene on top-growing cells, namely by rescuing them from chemically induced apoptosis or by stimulating cell division under serum starvation, respectively. Protein release from IBs seems to mechanistically mimic the sustained secretion of protein hormones from amyloid-like secretory granules in higher organisms. Conclusion: We propose bacterial IBs as biomimetic nanostructured scaffolds (bioscaffolds) suitable for tissue engineering that, while acting as adhesive materials, partially disintegrate for the slow release of their biologically active building blocks. The bottom-up delivery of protein drugs mediated by bioscaffolds offers a highly promising platform for emerging applications in regenerative medicine.

Original submitted 25 June 2012; Revised submitted 18 September 2012; Published online 8 February 2013

Keywords::

• biomaterial
• building block
• drug delivery
• scaffold
• tissue engineering

Financial & competing interests disclosure

This study was funded by Modalidad Infrastructuras Científico-Tecnológicas (MINECO; BFU2010-17450), Agència de Gestió d‘Ajuts Universitaris i de Recerca (AGAUR; 2009SGR-00108) and Centro de Investigación Biomédica En Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN, Spain). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008–2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. E García-Fruitós is supported by the Programa Personal de Técnico de Apoyo (Ministerio De Economia Y Competitividad). J Seras-Franzoso is recipient of a PIF doctoral fellowship from Universitat Autònoma de Barcelona, K Peebo of an Erasmus placement scholarship and A Villaverde of an ICREA ACADEMIA award. A Villaverde, E García-Fruitós and E Vazquez are coinventors of a patent (P200900045) on the use of inclusion bodies as reagents for mammalian cell culture. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The authors state that they have obtained appropriate institutional review board approval or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.

Acknowledgements

The authors wish to thank the Cell Culture Unit of the Servei de Cultius Cellulars, Producció d‘Anticossos i Citometria (SCAC), and Servei de Microscòpia, both at the Universitat Autònoma de Barcelona (UAB) and the Protein Production Platform (CIBER-BBN - UAB) for its helpful technical assistance.

Additional information

Funding

This study was funded by Modalidad Infrastructuras Científico-Tecnológicas (MINECO; BFU2010-17450), Agència de Gestió d‘Ajuts Universitaris i de Recerca (AGAUR; 2009SGR-00108) and Centro de Investigación Biomédica En Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN, Spain). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008–2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund. E García-Fruitós is supported by the Programa Personal de Técnico de Apoyo (Ministerio De Economia Y Competitividad). J Seras-Franzoso is recipient of a PIF doctoral fellowship from Universitat Autònoma de Barcelona, K Peebo of an Erasmus placement scholarship and A Villaverde of an ICREA ACADEMIA award. A Villaverde, E García-Fruitós and E Vazquez are coinventors of a patent (P200900045) on the use of inclusion bodies as reagents for mammalian cell culture. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Notes on contributors

Joaquin Seras-Franzoso

Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and Department de Genètica i de MicroBiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER–BBN), Bellaterra, 08193 Barcelona, Spain

Karl Peebo

Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and Competence Centre of Food & Fermentation Technologies, Akadeemia tee 15b, 12618 Tallinn, Estonia

José Luis Corchero

Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and Department de Genètica i de MicroBiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER–BBN), Bellaterra, 08193 Barcelona, Spain.

Penelope M Tsimbouri

Centre for Cell Engineering, University of Glasgow, College of Medical, Veterinary & Life Sciences, Glasgow, G12 8QQ , Scotland

Ugutz Unzueta

Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and Department de Genètica i de MicroBiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Bellaterra, 08193 Barcelona, Spain

Ursula Rinas

Institute of Technical Chemistry–Life Science, Leibniz University of Hannover, Callinstraße 5, D-30167 Hannover, Germany and Helmholtz Centre for Infection Research, Inhoffenstraße 7, D–38124 Braunschweig, Germanyand Helmholtz Centre for Infection Research, Inhoffenstraße 7, D–38124 Braunschweig, Germany.

Matthew J Dalby

Centre for Cell Engineering, University of Glasgow, College of Medical, Veterinary & Life Sciences, Glasgow, G12 8QQ , Scotland.

Esther Vazquez

Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and Department de Genètica i de MicroBiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Bellaterra, 08193 Barcelona, Spain.

Elena García-Fruitós

Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and Department de Genètica i de MicroBiologia, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain and CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER–BBN), Bellaterra, 08193 Barcelona, Spain