@article {15816, title = {Gradual pore formation in natural origin scaffolds throughout subcutaneous implantation}, journal = {Journal of Biomedical Materials Research: Part A}, volume = {100}, year = {2012}, month = {2012-02-16 00:00:00}, pages = {599-612}, publisher = {Wiley Periodicals, Inc}, abstract = {

This study used a rat\ subcutaneousimplantation\ model to investigate\ gradual\ in situ\ poreformation\ in a self-regulating degradable chitosan-based material, which comprises lysozyme incorporated into biomimetic calcium phosphate (CaP) coatings at the surface to control the scaffold degradation and subsequent\ poreformation. Specifically, the in vivo degradation of the\ scaffolds, the in situ\ poreformation, and the tissue response were investigated. Chitosan or chitosan/starch\ scaffolds\ were studied with and without a CaP coating in the presence or absence of lysozyme for a total of six experimental groups. Twenty-four\ scaffolds\ per group were implanted, and eight\ scaffolds\ were retrieved at each of three time points (3, 6, and 12 weeks). Harvested samples were analyzed for weight loss, microcomputed tomography, and histological analysis. All\ scaffolds\ showed pronounced weight loss and\ poreformation\ as a function of time. The highest weight loss was 29.8\% {\textpm} 1.5\%, obtained at week 12 for CaP chitosan/starchscaffolds\ with lysozyme incorporated. Moreover, all experimental groups showed a significant increase in porosity after 12 weeks. At all time points no adverse tissue reaction was observed, and as degradation increased, histological analysis showed cellular ingrowth\ throughout\ the implants. Using this innovative methodology, the ability to gradually generate pores in situ was clearly demonstrated in vivo.

}, keywords = {enzymes, in situ pore formation, in vivo degradation, natural origin materials, tissue response}, doi = {10.1002/jbm.a.33261}, author = {Martins, A. M. and Kretlow, J. D. and Costa-Pinto, A. R. and Malafaya, P. B. and Fernandes, E. M. and Neves, N. M. and Alves, C. M. and Mikos, A. G. and Kasper, F. K. and Reis, R. L.} }