Thermoreversible laminin‐functionalized hydrogel for neural tissue engineering

Abstract

Traumatic injury to the central nervous system (CNS) triggers cell death and deafferentation, which may activate a cascade of cellular and network disturbances. These events often result in the formation of irregularly shaped lesions comprised of necrotic tissue and/or a fluid‐filled cavity. Tissue engineering represents a promising treatment strategy for the injured neural tissue. To facilitate minimally invasive delivery of a tissue engineered system, a thermoreversible polymer is an attractive scaffold candidate. We have developed a bioactive scaffold for neural tissue engineering by tethering laminin‐1 (LN) to methylcellulose (MC), a thermoresponsive hydrogel. The base MC chain was oxidized via sodium m‐periodate to increase MC tethering capacity. Protein immobilization was facilitated by a Schiff base reaction between primary amine groups on LN and the carbonyl groups of the oxidized MC chain. Immunoassays demonstrated tethering of LN at 1.6 ± 0.5 ng of LN per milligram of MC. Rheological measurements for different MC–LN constructs indicated MC composition‐ and MC treatment‐dependent effects on solution–gelation transition temperature. Cellular assays with primary rat cortical neurons demonstrated enhanced cell adhesion and viability on LN‐functionalized MC when compared with base and oxidized MC. This bioadhesive thermoresponsive scaffold may provide a robust delivery vehicle to injured CNS tissue for neural cell transplantation strategies. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006