Tuning Physicochemical Properties of a Macroporous Polysaccharide-Based Scaffold for 3D Neuronal Culture

Abstract

Central nervous system (CNS) lesions are a leading cause of death and disability worldwide. Three-dimensional neural cultures in biomaterials offer more physiologically relevant models for disease studies, toxicity screenings or in vivo transplantations. Herein, we describe the development and use of pullulan/dextran polysaccharide-based scaffolds for 3D neuronal culture. We first assessed scaffolding properties upon variation of the concentration (1%, 1.5%, 3% w/w) of the cross-linking agent, sodium trimetaphosphate (STMP). The lower STMP concentration (1%) allowed us to generate scaffolds with higher porosity (59.9 ± 4.6%), faster degradation rate (5.11 ± 0.14 mg/min) and lower elastic modulus (384 ± 26 Pa) compared with 3% STMP scaffolds (47 ± 2.1%, 1.39 ± 0.03 mg/min, 916 ± 44 Pa, respectively). Using primary cultures of embryonic neurons from PGKCre, Rosa26tdTomato embryos, we observed that in 3D culture, embryonic neurons remained in aggregates within the scaffolds and did not attach, spread or differentiate. To enhance neuronal adhesion and neurite outgrowth, we then functionalized the 1% STMP scaffolds with laminin. We found that treatment of the scaffold with a 100 μg/mL solution of laminin, combined with a subsequent freeze-drying step, created a laminin mesh network that significantly enhanced embryonic neuron adhesion, neurite outgrowth and survival. Such scaffold therefore constitutes a promising neuron-compatible and biodegradable biomaterial.

Engineered human liver based on pullulan-dextran hydrogel promotes mice survival after liver failure

“…Pullulan-dextran cellularized Hyds have demonstrated good biocompatibility and suitable degradation times after engraftment in dorsal subcutaneous murine models [ [22] , [23] , [24] , [25] , [26] , [27] ]. However, their biocompatibility when seeded with hepatocytes in soft tissues with highly active metabolism was unknown.…”

“…The pullulan and dextran combination produces a soft viscoelastic hydrogel, easy to manipulate, potentially biocompatible and biodegradable [ [19] , [20] , [21] ]. In the last decade, dextran and pullulan have demonstrated their suitability in tissue engineering of various organs and tissues, and have been successfully implanted in rodents and large animals without inducing any major inflammatory response [ [22] , [23] , [24] , [25] , [26] , [27] ]. These materials have recently been approved for a clinical trial in bone regeneration [ 28 ].…”

Development of Novel Polysaccharide Membranes for Guided Bone Regeneration: In Vitro and In Vivo Evaluations

“…Bio-Gide ® demonstrated a bilayered structure with a smooth side composed of compact collagen fibers and a rough side with a fibrous open-pored pattern. Concerning Mb and Mb + HA, these porous pullulan/dextran 3D scaffolds have been extensively described by our team [33][34][35][36][37][38]. Both freeze-dried membranes have small pores (10-20 µm) on the smooth side.…”

“…Experimental and numerical simulations of the oxygen transport evidenced that the oxygen diffusion coefficient (D = 1.6 ± 0.5 × 10 −9 m 2 s −1 ) in the polysaccharide scaffolds was favorable for cell viability [35]. Additionally, the degradation kinetics in vivo can be tuned to parallel the tissue regeneration [38,39]. Moreover, the mechanical properties of these membranes are in the range of connective tissues of mammals [38,39].…”

“…Additionally, the degradation kinetics in vivo can be tuned to parallel the tissue regeneration [38,39]. Moreover, the mechanical properties of these membranes are in the range of connective tissues of mammals [38,39]. Surface mechanical properties of the membranes were evaluated here by nanoindentation.…”