Journal of Materials Science: Materials in Medicine

, Volume 22, Issue 12, pp 2641–2650 | Cite as

Enzymatic cross-linking of human recombinant elastin (HELP) as biomimetic approach in vascular tissue engineering

  • Sabrina Bozzini
  • Liliana Giuliano
  • Lina Altomare
  • Paola Petrini
  • Antonella Bandiera
  • Maria Teresa Conconi
  • Silvia Farè
  • Maria Cristina Tanzi


The use of polymers naturally occurring in the extracellular matrix (ECM) is a promising strategy in regenerative medicine. If compared to natural ECM proteins, proteins obtained by recombinant DNA technology have intrinsic advantages including reproducible macromolecular composition, sequence and molecular mass, and overcoming the potential pathogens transmission related to polymers of animal origin. Among ECM-mimicking materials, the family of recombinant elastin-like polymers is proposed for drug delivery applications and for the repair of damaged elastic tissues. This work aims to evaluate the potentiality of a recombinant human elastin-like polypeptide (HELP) as a base material of cross-linked matrices for regenerative medicine. The cross-linking of HELP was accomplished by the insertion of cross-linking sites, glutamine and lysine, in the recombinant polymer and generating ε-(γ-glutamyl) lysine links through the enzyme transglutaminase. The cross-linking efficacy was estimated by infrared spectroscopy. Freeze-dried cross-linked matrices showed swelling ratios in deionized water (≈2500%) with good structural stability up to 24 h. Mechanical compression tests, performed at 37°C in wet conditions, in a frequency sweep mode, indicated a storage modulus of 2/3 kPa, with no significant changes when increasing number of cycles or frequency. These results demonstrate the possibility to obtain mechanically resistant hydrogels via enzymatic crosslinking of HELP. Cytotoxicity tests of cross-linked HELP were performed with human umbilical vein endothelial cells, by use of transwell filter chambers for 1–7 days, or with its extracts in the opportune culture medium for 24 h. In both cases no cytotoxic effects were observed in comparison with the control cultures. On the whole, the results suggest the potentiality of this genetically engineered HELP for regenerative medicine applications, particularly for vascular tissue regeneration.


Storage Modulus Human Umbilical Vein Endothelial Cell Cytotoxicity Test Genipin Vascular Tissue Engineering 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This research was financed by Ministero dell’Istruzione, dell’Università e della Ricerca (MIUR), Italy, under PRIN Project 2007, funds to Prof. MC Tanzi.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Sabrina Bozzini
    • 1
  • Liliana Giuliano
    • 1
  • Lina Altomare
    • 1
  • Paola Petrini
    • 1
  • Antonella Bandiera
    • 2
  • Maria Teresa Conconi
    • 3
  • Silvia Farè
    • 1
  • Maria Cristina Tanzi
    • 1
  1. 1.Bioengineering Department, Biomaterials LaboratoryPolitecnico di MilanoMilanItaly
  2. 2.Department of Life SciencesUniversità degli Studi di TriesteTriesteItaly
  3. 3.Department of Pharmaceutical SciencesUniversità degli Studi di PadovaPadovaItaly

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