A combinatorial library approach was used to demonstrate that hydrogel scaffold modulus can enhance osteoblast differentiation driving formation of a 3-D graded tissue construct. Though many previous studies have focused on screening cell-material interactions using planar two-dimensional (2-D) substrates, biomaterials are commonly used in a 3-D scaffold format and cells behave more physiologically when cultured in 3-D. Osteoblasts were encapsulated in photopolymerizable poly(ethylene glycol) hydrogel gradient libraries spanning a ≈30-fold range in modulus. Increasing modulus caused increased osteoblast differentiation and mineralization leading to visible gradients of mineral ideal for seamless integration of tissue-engineered bone with softer tissues such as ligament without the use of differentiation supplements or bioactive factors. These results demonstrate that the hydrogel scaffold library platform can be used for systematically screening cell response to scaffold properties in 3-D, scaffold modulus influences osteoblast behavior in 3-D and the scaffold libraries can be applied for generating functionally graded tissues.
Citation: Nature Materials
Pub Type: Journals
Combinatorial methods, polymer scaffold, bimoaterials, tissue engineering, osteoblast, osteogenesis, modulus, hydrogel, functionally graded materials, cell differentiation, cell viability, 3-d culture