gms | German Medical Science

127. Kongress der Deutschen Gesellschaft für Chirurgie

Deutsche Gesellschaft für Chirurgie

20.04. - 23.04.2010, Berlin

Gene activation of collagen scaffolds to enhance angiogenesis during dermal regeneration

Meeting Abstract

  • Ann Reckhenrich - Klinikum rechts der Isar der TUM, Institute of Experimental Oncology, München, Deutschland
  • Tomas Egana - Klinikum rechts der Isar der TUM, Plastic and Hand Surgery, München, Deutschland
  • Ursula Hopfner - Klinikum rechts der Isar der TUM, Plastic and Hand Surgery, München, Deutschland
  • Mathias Kremer - Universität zu Lübeck, Plastic and Hand Surgery, Lübeck, Deutschland
  • Hans-Günther Machens - Klinikum rechts der Isar, Technische Universität München, Klinik und Poliklinik für Plastische Chirurgie und Handchirurgie, München, Deutschland
  • Christian Plank - Klinikum rechts der Isar der TUM, Institute of Experimental Oncology, München, Deutschland

Deutsche Gesellschaft für Chirurgie. 127. Kongress der Deutschen Gesellschaft für Chirurgie. Berlin, 20.-23.04.2010. Düsseldorf: German Medical Science GMS Publishing House; 2010. Doc10dgch174

DOI: 10.3205/10dgch174, URN: urn:nbn:de:0183-10dgch1749

Published: May 17, 2010

© 2010 Reckhenrich et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

Text

Introduction: In order to enhance vascularisation, the combination of gene therapy and scaffolds for tissue regeneration offers the opportunity to temporarily induce angiogenesis in vivo. In this study we developed a new approach to activate biomaterials by combining their use with non viral gene vectors encoding for therapeutic proteins.

Materials and methods: Copolymer-protected polyethylenimine (PEI)-DNA vectors were incorporated in a commercially available collagen scaffold for dermal regeneration (Integra Matrix). Vectors encoding for Metridia luciferase and NIH 3T3 mouse fibroblasts were used to determine the optimal DNA concentration in the scaffolds. Next scaffolds were activated with vectors encoding for VEGF165 and cells were seeded. After, cell distribution and their attachment to the scaffolds were evaluated by fluorescence microscopy, cell viability and proliferation by metabolic MTT assays, and the release of VEGF165 was evaluated by ELISA.

Results: DNA was incorporated at concentrations of 6.25, 12.5, 25 and 50 µg per scaffold (28 mg). No toxicity effects were observed in seeded cells and release of Metridia luciferase was detected in vitro for at least 10 weeks. A peak of expression was observed at day 5 to 9 and maximum release was obtained with the use of 12.5 µg of DNA per 28 mg of scaffold. After, vector encoding for VEGF165 was incorporated in Integra matrix in a concentration of 2.3 µg DNA/mg scaffold. Results show that after seeding, NIH 3T3 fibroblasts were homogeneously distributed forming focal adhesions with the scaffold. Moreover, the presence of DNA-Polyplexes did not affect cell viability and proliferation. Finally, transient release of VEGF was observed for up to 3 weeks with a peak of expression of 7 ng/ml at day 5.

Conclusion: Combined use of collagen scaffolds and copolymer-protected polyethylenimine (PEI)-DNA vectors, allows inducing local release of therapeutic proteins without cell toxicity in vitro. Such technologies may have tremendous impact in the field of tissue engineering and regenerative medicine. Preclinical studies with the use of genetically activated scaffolds are already under evaluation.