Effect of Chitosan on Alginate-Based Macroporous Hydrogels for the Capture of Glioblastoma Cancer Cells

Glioblastoma multiforme is a type of brain cancer associated with a very low survival rate since a large number of cancer cells remain infiltrated in the brain despite the treatments currently available. This work presents a macroporous hydrogel trap, destined to be implanted in the surgical cavity following tumor resection and designed to attract and retain cancer cells, in order to eliminate them afterward with a lethal dose of stereotactic radiotherapy. The biocompatible hydrogel formulation comprises sodium alginate (SA) and chitosan (CHI) bearing complementary electrostatic charges and stabilizing the gels in saline and cell culture media, as compared to pristine SA gels. The highly controlled and interconnected porosity, characterized by X-ray microCT, yields mechanical properties comparable to those of brain tissues and allows F98 glioblastoma cells to penetrate the gels within the entire volume, as confirmed by fluorescence microscopy. The addition of a grafted -RGD peptide on SA, combined with CHI, significantly enhances the adhesion and retention of F98 cells within the gels. Overall, the best compromise between low proliferation and a high level of accumulation and retention of F98 cells was obtained with the hydrogel formulated with 1% SA and 0.2% CHI, without the -RGD adhesion peptide.