Synergistic effect of bimodal pore distribution and artificial extracellular matrices in polymeric scaffolds on osteogenic differentiation of human mesenchymal stem cells

Surface-Modified Poly(l-lactide-co-glycolide) Scaffolds for the Treatment of Osteochondral Critical Size Defects—In Vivo Studies on Rabbits

“…The average pore size was between 250 and 320 µm, thus similar to the size of NaCl grains used as porogens. Scaffold porosity of 85% corresponded to volume faction of porogen used in the manufacturing step as shown in our earlier work [ 22 ]. Modification with collagen did not significantly influence morphology and porosity of the scaffolds.…”

“…In our study, NaCl was used as a porogen. SEM analyses revealed that the pore size in the scaffolds was determined by the size of NaCl grains used for scaffold fabrication [ 21 , 22 , 28 ]. What is more, the pores were interconnected, which is particularly beneficial for tissue regeneration purposes, as after the implantation, body fluids, nutrients, and cells will be able to penetrate the whole volume of the scaffold.…”

“…In our more recent study, we showed that PLGA modification with hydroxyapatite (HAp) deposited by biomimetic approach is beneficial for osteoblast adhesion, infiltration, and proliferation in the entire volume of porous scaffold [ 21 ]. Moreover, we found that modification of the PLGA scaffolds with artificial extracellular matrices (ECM) containing collagen type I and sulfated hyaluronic acid is beneficial for early and late osteogenic differentiation and mineralization of human mesenchymal stem cells (hMSC) [ 22 ], thus promising for BTE. To go a step further with possible translation, the scaffolds should be tested in a model more relevant to clinical application.…”

Poly(lactic-co-glycolic acid)-based composite bone-substitute materials

“…Moreover, it is difficult for the culture medium to enter the high-porosity PLGA scaffold under normal circumstances, which will affect the efficiency of cell seeding [ 87 ]. These problems might be effectively solved by covering the surface of the materials with an artificial extracellular matrix [ 88 ]. Adding fibronectin, vitronectin, Col, or fibrin to the surface of materials will enhance the adhesion of cells to the polymer scaffolds [ 89 ].…”

“…The results showed that the content of alkaline phosphatase (ALP) in the medium increased, and the ability of stem cells to differentiate into osteoblasts was enhanced in the presence of an artificial extracellular matrix. The researchers further explored the influence of the surface microstructures of PLGA scaffolds on the differentiation of hMSCs [ 88 ]. They prepared a PLGA scaffold with a pore diameter of several hundreds of micrometers and another PLGA scaffold with two different pore diameters of several micrometers and hundreds of micrometers.…”