Initial Boost Release of Transforming Growth Factor-β3 and Chondrogenesis by Freeze-Dried Bioactive Polymer Scaffolds

Abstract

In cartilage regeneration, bio-activated implants are used in stem and progenitor cell-based microfracture cartilage repair procedures. Our aim was to analyze the chondrogenic potential of freeze-dried resorbable polymer-based polyglycolic acid (PGA) scaffolds bio-activated with transforming growth factor-β3 (TGFB3) on human subchondral mesenchymal progenitor cells known from microfracture. Progenitor cells derived from femur heads were cultured in the presence of freeze-dried TGFB3 in high-density pellet culture and in freeze-dried TGFB3-PGA scaffolds for chondrogenic differentiation. Progenitor cell cultures in PGA scaffolds as well as pellet cultures with and without continuous application of TGFB3 served as controls. Release studies showed that freeze-dried TGFB3-PGA scaffolds facilitate a rapid, initial boost-like release of 71.5% of TGFB3 in the first 10 h. Gene expression analysis and histology showed induction of typical chondrogenic markers like type II collagen and formation of cartilaginous tissue in TGFB3-PGA scaffolds seeded with subchondral progenitor cells and in pellet cultures stimulated with freeze-dried TGFB3. Chondrogenic differentiation in freeze-dried TGFB3-PGA scaffolds was comparable to cultures receiving TGFB3 continuously, while non-stimulated controls did not show chondrogenesis during prolonged culture for 14 days. These results suggest that bio-activated, freeze-dried TGFB3-PGA scaffolds have chondrogenic potential and are a promising tool for stem cell-mediated cartilage regeneration.

Proliferation, Migration, and ECM Formation Potential of Human Annulus Fibrosus Cells Is Independent of Degeneration Status

“…Three-dimensional cultures were prepared as described previously. 21 Briefly, nonwoven PGA-HA scaffolds (BioTissue AG, Switzerland) with a pore size up to 200 µm were cut into pieces of 10 × 10 × 1.1 mm. Human AF cells (n = 5 for early and advanced degenerative tissue each) were harvested after passage 3 and counted.…”

Genetic Engineering of Mesenchymal Stem Cells for Differential Matrix Deposition on 3D Woven Scaffolds

“…[28][29][30][31][32] However, MSCs require high concentrations of exogenous growth factors to enter distinct lineage programs in vitro. [33][34][35] For example, transforming growth factor b 3 (TGFb3) is commonly used to induce MSC chondrogenesis, [36][37][38][39] while bone morphogenic protein 2 (BMP2) is often used to induce osteogenesis. [40][41][42] These growth factors and environmental cues that define chondrogenic differentiation may interfere with osteogenic differentiation, [43][44][45][46] and vice-versa.…”

Meniscus‐shaped cell‐free polyglycolic acid scaffold for meniscal repair in a sheep model

“…To analyze collagen type I deposition cryo-sections were stained using a primary polyclonal rabbit anti-human collagen alpha-1 type I (R1038, Acris, Germany) together with a colorimetric detection kit (K4008, EnVision ® + System-HRP [AEC] for use with rabbit primary antibodies, Dako, Denmark) as described before (Kruger, Ketzmar, et al, 2014). Histomorphometric analyses of the stained area were performed as previously published against the control (Kruger, Machens, Lahner, Endres, & Kaps, 2014 3 | RESULTS…”