Fibronectin and culture temperature modulate the efficacy of an avidin–biotin binding system for chondrocyte adhesion and growth on biodegradable polymers

Abstract

Cell adhesion to a scaffold is a prerequisite for tissue engineering. Many studies have been focused on enhancing cell adhesion to synthetic materials that are used for scaffold fabrication. Previously, we showed that immobilization of biotin molecules to chondrocyte surfaces enhanced cell adhesion to avidin-coated biodegradable polymers such as poly-L-lactic acid, poly-D,L-lactic acid and polycaprolactone. However, the endocytosis of cell membrane biotin molecules decreases binding strength between biotinylated-chondrocytes (B-chondrocytes) and avidin-coated substrata, and therefore decreases cell spreading and discourages long-term chondrocytes culture. In this study, we proposed two strategies to solve the shortcoming of the avidin-biotin binding system. First, the avidin-biotin binding system is combined with the intrinsic integrin-dependent adhesion systems in order to enhance long-term cell culture. Second, the incubation temperature is lowered in order to slow down the endocytosis process. We found that the avidin-biotin binding system in combination with FN-integrin binding system enhanced cell adhesion, cell spreading and cell growth. Decrease of cell culture temperature to 4 degrees C enhanced the adhesion of B-chondrocytes to the avidin-coated surfaces, but decreased cell viability and proliferation, compared to culture temperature of 37 degrees C. Whether there is an optimal seeding temperature between 4 and 37 degrees C for both adhesion and proliferation of B-chondrocytes needs further investigation. Our results indicated that modulation of the adhesion conditions could further enhance the efficacy of the avidin-biotin binding system in mediating cell adhesion, and subsequent tissue culture.

Glycine-spacers influence functional motifs exposure and self-assembling propensity of functionalized substrates tailored for neural stem cell cultures

“…A considerable number of interdisciplinary publications, from physics to biology, describe guidelines to fabricate new nano-biomaterials for specific applications (Reddi, 2000; Drotleff et al, 2004; Hirst and Smith, 2004; Tsai et al, 2007; Ulijn and Smith, 2008). Molecular self-assembly became an alternative paradigm to create functional nanostructures using spontaneous diffusion and specific association of molecules directed by weak interactions (Weigel et al, 2006).…”

Effects of an avidin‐biotin binding system on Schwann cells attachment, proliferation, and gene expressions onto electrospun scaffolds

“…But these synthetic polymers lack adhesion proteins for cells attachment. It has been demonstrated that effective SCs attachment was a prerequisite for the successful construction of tissue‐engineered nerve 6…”

“…It has been demonstrated that effective SCs attachment was a prerequisite for the successful construction of tissue-engineered nerve. 6 Several strategies have been used to promote SCs attaching onto the scaffolds, and the most favored method is to physically absorb or chemically conjugate extracellular matrix (ECM) adhesion proteins to biomaterial surfaces, 7,8 which is based on the formation of integrin-mediated bonds between cell adhesion molecules on substrata and integrin receptors in the cell membrane. But there are two disadvantages of this approach.…”

Non-viral gene delivery carrier and its three-dimensional transfection system

“…The immobilization of vectors to biomaterials, also termed substrate-mediated delivery or reverse transfection, provides a method for gene delivery from scaffolds formed by processes that would normally inactivate the vector if they were encapsulated during fabrication (Bajaj et al, 2001). The gene complexes could be immobilized to biomaterials through non-specific mechanisms, including hydrophobic, electrostatic, and van der Waals interactions (De Laporte and Shea, 2007), as well as specific interactions such as in the form of antigen-antibody or biotin-avidin (Tsai et al, 2007;Uchimura et al, 2007).…”