Endothelialization of chitosan porous conduits via immobilization of a recombin...

• Author(s): Amaral, I. F. ; Neiva, I. ; Silva, F. Ferreira da ; Sousa, S. R. ; Piloto, A. M. ; Lopes, C. D. F. ; Barbosa, Mário A. ; Kirkpatrick, C. J. ; Pêgo, A. P.
• Date: 2013
• Persistent ID: http://hdl.handle.net/10400.22/3343
• Origin: Repositório Científico do Instituto Politécnico do Porto
• Subject(s): Three-dimensional scaffolds; Surface grafting; Protein radiolabelling; Protein conformation; Spinal cord injury
• Document Type: Article
• Language: English

Description

The present study aimed to develop a pre-endothelialized chitosan (CH) porous hollowed scaffold for application in spinal cord regenerative therapies. CH conduits with different degrees of acetylation (DA; 4% and 15%) were prepared, characterized (microstructure, porosity and water uptake) and functionalized with a recombinant fragment of human fibronectin (rhFNIII7–10). Immobilized rhFNIII7–10 was characterized in terms of amount (125I-radiolabelling), exposure of cell-binding domains (immunofluorescence) and ability to mediate endothelial cell (EC) adhesion and cytoskeletal rearrangement. Functionalized conduits revealed a linear increase in immobilized rhFNIII7–10 with rhFNIII7–10 concentration, and, for the same concentration, higher amounts of rhFNIII7–10 on DA 4% compared with DA 15%. Moreover, rhFNIII7–10 concentrations as low as 5 and 20 lgml 1 in the coupling reaction were shown to provide DA 4% and 15% scaffolds, respectively, with levels of exposed cell-binding domains exceeding those observed on the control (DA 4% scaffolds incubated in a 20 lgml 1 human fibronectin solution). These grafting conditions proved to be effective in mediating EC adhesion/cytoskeletal organization on CH with DA 4% and 15%, without affecting the endothelial angiogenic potential. rhFNIII7–10 grafting to CH could be a strategy of particular interest in tissue engineering applications requiring the use of endothelialized porous matrices with tunable degradation rates.