Induction of Myofibroblastic DifferentiationIn Vitroby Covalently Immobilized Transforming Growth Factor-β₁

Abstract

Growth factors are an important tool in tissue engineering. Bone morphogenetic protein-2 and transforming growth factor-beta(1) (TGF-beta(1)) are used to provide bioactivity to surgical implants and tissue substitute materials. Mostly growth factors are used in soluble or adsorbed form. However, simple adsorption of proteins to surfaces is always accompanied by reduced stability and undefined pharmacokinetics. This study aims to prove that TGF-beta(1) can be covalently immobilized to functionalized surfaces, maintaining its ability to induce myofibroblastic differentiation of normal human dermal fibroblasts. In vivo, fibroblasts differentiate to myofibroblasts (MFs) during soft tissue healing by the action of TGF-beta(1). As surfaces for our experiments, we used slides bearing aldehyde, epoxy, or amino groups. For our in vitro cell culture experiments, we used the expression of alpha-smooth muscle actin as a marker for MFs after immunochemical staining. Using the aldehyde and the epoxy slides, we were able to demonstrate the activity of immobilized TGF-beta(1) through a significant increase in MF differentiation rate. A simple immunological test was established to detect TGF-beta(1) on the surfaces. This technology enables the creation of molecular "landscapes" consisting of several factors arranged in a distinct spatial pattern and immobilized on appropriate surfaces.

Controlled Delivery of Transforming Growth Factor β1 by Self-Assembling Peptide Hydrogels Induces Chondrogenesis of Bone Marrow Stromal Cells and Modulates Smad2/3 Signaling

“…2). This is in contrast to recent reports where TGF-b1 covalently tethered to bioactive twodimensional surfaces induced myofibroblast differentiation, 41 increased matrix production of vascular smooth muscle cells, 42 and initiated cartilage-like ECM production in a magnetic-bead pellet culture system. 12 In addition, biotinstreptavidin sandwich tethered IGF-I in self-assembling peptide hydrogels improved cell survival and function after experimentally induced myocardial infarction in a rat model.…”

Engineered Microtissues Formed by Schiff Base Crosslinking Restore the Chondrogenic Potential of Aged Mesenchymal Stem Cells

“…Though the TGF‐β3 release profile followed diffusion‐based first order kinetics, it is also possible that some TGF‐β3 is covalently immobilized in the polysaccharide network via Schiff base reaction between its ε‐lysine amino acids and unreacted free aldehydes present in oxAlg, where it would continue to remain biologically active for stimulation of differentiation . By day 5, release of TGF‐β3 was complete for all doses.…”

From natural bone grafts to tissue engineering therapeutics: Brainstorming on pharmaceutical formulative requirements and challenges

“…12C), or (ii) binding them to the graft. 219,430,475,507,508 In these variants, molecule release is retarded by the diffusion through the coating layer, or the breaking of chemical bonds. Hence, one might have a release of selected molecules slower than that occurring with the third strategy (i.e., molecule absorption).…”