Sustained Release of TGFβ3 from PLGA Microspheres and Its Effect on Early Osteogenic Differentiation of Human Mesenchymal Stem Cells

Abstract

Despite the widespread role of transforming growth factor-β3 (TGFβ3) in wound healing and tissue regeneration, its long-term controlled release has not been demonstrated. Here, we report microencapsulation of TGFβ3 in poly-d-l-lactic-co-glycolic acid (PLGA) microspheres and determine its bioactivity. The release profiles of PLGA-encapsulated TGFβ3 with 50:50 and 75:25 PLA:PGA ratios differed throughout the experimental period. To compare sterilization modalities of microspheres, bFGF was encapsulated in 50:50 PLGA microspheres and subjected to ethylene oxide (EO) gas, radiofrequency glow discharge (RFGD), or ultraviolet (UV) light. The release of bFGF was significantly attenuated by UV light, but not significantly altered by either EO or RFGD. To verify its bioactivity, TGFβ3 (1.35 ng/mL) was control-released to the culture of human mesenchymal stem cells (hMSC) under induced osteogenic differentiation. Alkaline phosphatase staining intensity was markedly reduced 1 week after exposing hMSC-derived osteogenic cells to TGFβ3. This was confirmed by lower alkaline phosphatase activity (2.25 ± 0.57 mU/mL/ng DNA) than controls (TGFβ3-free) at 5.8 ± 0.9 mU/mL/ng DNA (p < 0.05). Control-released TGFβ3 bioactivity was further confirmed by lack of significant differences in alkaline phosphatase upon direct addition of 1.35 ng/mL TGFβ3 to cell culture (p > 0.05). These findings provide baseline data for potential uses of microencapsulated TGFβ3 in wound healing and tissue-engineering applications.

Three-Dimensional Printed Multiphase Scaffolds for Regeneration of Periodontium Complex

“…37 CTGF was selected for its potency to stimulate fibroblastic differentiation. 31,38 BMP2 was selected for its ability to promote osteogenesis. 32 Natively, amelogenin is expressed by ameloblasts and was selected to simulate odontogenesis and/or cementogenesis, its effect to promote differentiation of odotoblasts and cementoblasts.…”

“…PLGA mS-encapsulating these bioactive cues were prepared using double-emulsion technique as per our previous work. 31,38 In vitro release kinetics showed timed extrusion of the encapsulated cues up to the tested 6 weeks (Supplementary Fig. S1; Supplementary Data are available online at www .liebertpub.com/tea).…”

Biomimetic materials for tissue engineering

“…However, microspheres, when used alone, often coalesce or migrate, which may not allow the controlled spatial delivery. In tissue engineering, it is desirable to controlled release biological molecules within the scaffold [2,3,[129][130][131][132][133][134]. Biological factors have been directly added into a polymer solution or emulsion to fabricate scaffolds [135,136].…”

In vitro and in vivo effects of PDGF-BB delivery strategies on tendon healing: a review

“…Enzymes that are present at inflamed wound sites and found in plasma, by oxidation or hydrolysis, can affect the degradation rate of the material and, thus, influence the release profile from the device. Also, sterilisation methods, as part of in vivo procedures and regulations can affect the material degradation (Savaris et al, 2016) and bioactivity of the incorporated growth factors (Mainil-Varlet et al, 1997;Moioli et al, 2006). Furthermore, the stability and bioactivity of the released growth factor at the wound site can differ from the in vitro conditions.…”