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Coatings produced from extracellular matrixes (ECMs) have emerged as promising surfaces for the improved ex vivo expansion of mesenchymal stem cells (MSCs). However, identifying a readily available source of ECM to generate these coatings is currently the bottleneck of this technology. In this study, we assessed if ECM coatings derived from decellularized fetal membranes were a suitable substrate for MSC expansion. We separated and decellularized the two main components of the fetal membranes, the amnion and the chorion. Characterization of the decellularized membranes revealed that each membrane component has a distinct composition, implying that coatings produced from these materials would have unique biological properties. The membranes were processed further to produce solubilized forms of the decellularized amniotic membrane (s-dAM) and decellularized chorionic membrane (s-dCM). On s-dAM coatings decidual MSCs (DMSC) were more proliferative than those cultured on tissue culture plastic alone or on Matrigel coatings; were smaller in size (a measure of MSC potency); exhibited greater adipogenic differentiation capacity; and improved osteogenic capacity. Additionally, long term culture studies showed late passage DMSCs (passage 8) cultured on s-dAM showed a decrease in cell diameter over three passages. These data support the use of s-dAM as a substrate for improved MSC expansion. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 232-242, 2019.

A family of methacrylic terpolymer biomaterials was electrospun into three-dimensional fibrous scaffolds. The glass transition temperature of the polymer correlates with the morphology of the resulting scaffold. Glassy materials produce scaffolds with discrete fibers and a high percent void space (84%) while the rubbery materials produced scaffolds with fused fibers and a much lower percent void space (18%). By electrospinning onto a rotating mandrel, aligned fiber scaffolds were fabricated, and it was shown that controlling the rotation speed of the collector allowed for control over the degree of fiber alignment. The electrospinning was shown to not degrade the number average molecular weight of the polymer chains. Human umbilical vein endothelial cells (HUVECs) were seeded onto the electrospun scaffolds under static conditions and it was found that the morphology of the scaffold controlled the cellular proliferation, the metabolic activity, and the morphology of adherent cells. In particular, HUVECs seeded onto low void space scaffolds exhibited enhanced cellular spreading, enzymatic activity, and proliferation. HUVECs seeded onto aligned fiber scaffolds did not demonstrate increased proliferation; however, the cells did organize themselves in the direction of fiber alignment resulting in cells with elongated morphology.

A terpolymer copolymerized from hexyl methacrylate, methyl methacrylate, and poly(ethylene glycol) methacrylate (PEGMA) was synthesized. Polymers containing 0-25 mol % PEGMA were studied. As the mole fraction of PEGMA in the polymer chains increased, the material becomes more hydrophilic as observed by a decrease in the contact angle of water (81 degrees -68 degrees) and an increase in the equilibrium water absorption (0.7-237 wt %). Furthermore, the material shows nonfouling interfacial properties through resistance to protein adsorption and cellular attachment. A total of 1.2 microg/cm(2) fibrinogen, 18,000 HUVECs/cm(2), and 3,000,000 platelets/cm(2) adsorbed or adhered on non-PEGylated materials, whereas very low amounts of protein or cells were observed on materials containing >or=15 mol % PEGMA. Being thermoplastic, the polymer can be processed postsynthesis. To illustrate the processing capabilities of the material, polymer solutions were electrospun into nonwoven fibrous scaffold, which also retained their nonfouling character.