3D Poly(Lactic Acid) Scaffolds Promote Different Behaviors on Endothelial Progenitors and Adipose-Derived Stromal Cells in Comparison With Standard 2D Cultures

Abstract

Tissue engineering is a branch of regenerative medicine, which comprises the combination of biomaterials, cells and other bioactive molecules to regenerate tissues. Biomaterial scaffolds act as substrate and as physical support for cells and they can also reproduce the extracellular matrix cues. Although tissue engineering applications in cellular therapy tend to focus on the use of specialized cells from particular tissues or stem cells, little attention has been paid to endothelial progenitors, an important cell type in tissue regeneration. We combined 3D printed poly(lactic acid) scaffolds comprising two different pore sizes with human adipose-derived stromal cells (hASCs) and expanded CD133+ cells to evaluate how these two cell types respond to the different architectures. hASCs represent an ideal source of cells for tissue engineering applications due to their low immunogenicity, paracrine activity and ability to differentiate. Expanded CD133+ cells were isolated from umbilical cord blood and represent a source of endothelial-like cells with angiogenic potential. Fluorescence microscopy and scanning electron microscopy showed that both cell types were able to adhere to the scaffolds and maintain their characteristic morphologies. The porous PLA scaffolds stimulated cell cycle progression of hASCs but led to an arrest in the G1 phase and reduced proliferation of expanded CD133+ cells. Also, while hASCs maintained their undifferentiated profile after 7 days of culture on the scaffolds, expanded CD133+ cells presented a reduction of the von Willebrand factor (vWF), which affected the cells’ angiogenic potential. We did not observe changes in cell behavior for any of the parameters analyzed between the scaffolds with different pore sizes, but the 3D environment created by the scaffolds had different effects on the cell types tested. Unlike the extensively used mesenchymal stem cell types, the 3D PLA scaffolds led to opposite behaviors of the expanded CD133+ cells in terms of cytotoxicity, proliferation and immunophenotype. The results obtained reinforce the importance of studying how different cell types respond to 3D culture systems when considering the scaffold approach for tissue engineering.

Extracellular matrix stiffness mediates radiosensitivity in a 3D nasopharyngeal carcinoma model

“…Another phenomenon observed in the present study was G1/S phase arrest occurring in 3D cultured cells. This was previously also observed in 3D cultured human adipose-derived stromal cells [ 26 ] and in tumors treated with drugs or radiation [ 31 , 32 ]. A previous study demonstrated a correlation between radioresistance and the G1 phase of the cell cycle, particularly in KRAS mutant cells arrested in the G1 phase [ 33 ].…”

“…Reduced proliferation ability in 3D cultured cells compared with 2D cultured cells has been reported in several papers [ 26 – 28 ], while other studies hold the opposite conclusion [ 29 , 30 ]. Despite the fact that the colony formation rate in 3D cultured cells was lower than that in 2D cultured cells, the diameter of the colonies was larger, indicating a greater number of cells per colony.…”

Carboxymethylated and Sulfated Furcellaran from Furcellaria lumbricalis and Its Immobilization on PLA Scaffolds

“…As presented in Figure 9 , untreated PLA scaffold show biocompatibility despite its hydrophobic nature, low surface energy, and absence of reactive functional groups. The PLA scaffold was not cytotoxic also in the study of Biagini et al [ 58 ] for hASCs and expanded CD133 + cells. Other investigations have demonstrated that PLA scaffolds enhance the proliferation of fibroblasts [ 59 ].…”

Development of a Composite Hydrogel Containing Statistically Optimized PDGF-Loaded Polymeric Nanospheres for Skin Regeneration: In Vitro Evaluation and Stem Cell Differentiation Studies

“…After 5 h of cell culture on the scaffold, the culture medium was discarded; the scaffold was washed twice with PBS and fixed with 2.5% glutaraldehyde for 2 h. Then, glutaraldehyde was drained, and after washing the scaffold with PBS, we added 1% osmium tetroxide solution and allowed the scaffold to remain in the incubator for 1.5 h. 52 We drained the solution and placed the samples in a desiccator overnight and sent them for SEM imaging the next day.…”