Poly(L-co-D,L lactic acid-co-Trimethylene Carbonate) 3D printed scaffold cultivated with mesenchymal stem cells directed to bone reconstruction: In vitro and in vivo studies

Abstract

A recent and quite promising technique for bone tissue engineering is the 3D printing, peculiarly regarding the production of high-quality scaffolds. The 3D printed scaffold strictly provides suitable characteristics for living cells, in order to induce treatment, reconstruction and substitution of injured tissue. The purpose of this work was to evaluate the behavior of the 3D scaffold based on Poly(L-co-D,L lactic acid-co-Trimethylene Carbonate) (PLDLA-TMC), which was designed in Solidworks™ software, projected in 3D Slicer™, 3D printed in filament extrusion, cultured with mesenchymal stem cells (MSCs) and tested in vitro and in vivo models. For in vitro study, the MSCs were seeded in a PLDLA-TMC 3D scaffold with 600 μm pore size and submitted to proliferation and osteogenic differentiation. The in vivo assays implanted the PLDLA-TMC scaffolds with or without MSCs in the calvaria of Wistar rats submitted to 8 mm cranial bone defect, in periods of 8–12 weeks. The results showed that PLDLA-TMC 3D scaffolds favored adherence and cell growth, and suggests an osteoinductive activity, which means that the material itself augmented cellular differentiation. The implanted PLDLA-TMC containing MSCs, showed better results after 12 weeks prior grafting, due the absence of inflammatory processes, enlarged regeneration of bone tissue and facilitated angiogenesis. Notwithstanding, the 3D PLDLA-TMC itself implanted enriched tissue repair; the addition of cells known to upregulate tissue healing reinforce the perspectives for the PLDLA-TMC applications in the field of bone tissue engineering in clinical trials.

Meniscal repair with additive manufacture of bioresorbable polymer: From physicochemical characterization to implantation of 3D printed poly (L-co-D, L lactide-co-trimethylene carbonate) with autologous stem cells in rabbits

“…Although the calcification zone in the tidemark was not as clear as the original cartilage the transition of subchondral bone is welldefined but contains high lacunar spaces. These results demonstrated that the presence of the PLDLA-TMC scaffold aided in the meniscal regeneration process, as shown by Esposito et al 35 It is evident that the results obtained with the implantation of a polymeric scaffold, without cell precultivation, provide better outcomes when compared to the empty defect group, 13 which represents an advancement and an alternative for the treatment of meniscus injuries in orthopedic practice.…”

“…8 The processing conditions applied indicated that the PLDLA-TMC polymeric scaffold presented a molecular weight of 192.764 g.mol À1 , which is a desired molecular weight requirement to the mechanical properties for a wide range of applications in bone/cartilaginous tissue engineering approaches, as previously reported. 13…”

“…Furthermore, the stem cells, when associated and implanted with the biomaterial, as They are previously differentiated, accelerate the regenerative process of the tissue. [10][11][12] Asami and collaborators 13 showed that the MSCs associated with the PLDLA-TMC scaffold improved bone regeneration in critical cranial defects in Wistar rats.…”

“…Furthermore, investigations by Wang et al 15 underscore that attributes such as mechanical and biodegradable characteristics, porous structure, as well as the facilitation of chondrocyte stimulation and specificity, represent essential strategies for biomaterials in this area. Consequently, the investigation of the manipulation properties of the PLDLA-TMC terpolymer assumes significant importance, given its nuanced characteristics for tissue engineering 13 and its compatibility with the 3D printing process, 16 standing out as a promising new material for the regeneration of cartilage tissue.…”