Stephen J. Florczyk and Miqin Zhang

Dept. of Materials Sci. & Eng., University of Washington, Seattle, WA


Biomedical challenges afflict our society and strain the healthcare system. Some of these challenges include the need for tissue replacement and cancer. Tissue engineering has the potential to address the need for tissue replacement by generating in vitro cultured synthetic grafts, which can be used instead of tissue grafts. The use of tissue engineering principles can also be applied to cancer research to model the tumor microenvironment and provide a means to further understand cancer and to evaluate therapies.


Three-dimensional (3D) porous scaffolds were prepared from a polyelectrolyte complex (PEC) solution of the natural polymers chitosan and alginate. These polymers independently have good biological properties and the chitosan-alginate (CA) PEC has improved properties. The CA scaffolds were prepared by casting the CA PEC solution, freezing, then lyophilizing to yield a 3D porous scaffold.


The CA scaffolds were evaluated for functional bone tissue engineering (BTE) applications in a rat calvarial defect model. The trial compared an empty defect to untreated CA scaffolds and CA scaffolds with biological treatments. The trial demonstrated that the untreated CA scaffold had a good osteogenic response and the CA scaffold group treated with BMP-2 had the greatest osteogenic response compared to the empty defect.


The CA scaffolds were also evaluated in in vitro cancer research applications using human prostate cancer (PCa) cells. These PCa cells were cultured on the CA scaffolds, then treated with human peripheral blood lymphocytes (PBLs) and evaluated for their interaction. The CA scaffolds supported PCa culture and PBLs interaction with PCa cells.


This work has demonstrated the utility of the 3D porous CA scaffolds for functional bone tissue engineering and cancer research applications.