Effect of pore sizes of PLGA scaffolds on mechanical properties and cell behaviour for nucleus pulposus regenerationin vivo

Abstract

This study investigated the influence of pore sizes of poly(lactic-co-glycolic acid) (PLGA) scaffolds on the compressive strength of tissue-engineered biodiscs and selection of the best suitable pore size for cells to grow in vivo. PLGA scaffolds were fabricated by solvent casting/salt-leaching with pore sizes of 90-180, 180-250, 250-355 and 355-425 µm. Nucleus pulposus (NP) cells were seeded on PLGA scaffolds with various pore sizes. Each sample was harvested at each time point, after retrieval of PLGA scaffolds seeded with NP cells, which were implanted into subcutaneous spaces in nude mice at 4 and 6 weeks. MTT assay, glycosaminoglycan (GAG) assay, haematoxylin and eosin (H&E) staining, safranin O staining and immunohistochemistry (for collagen type II) were performed at each time point. As the pores became smaller, the value of the compressive strength of the scaffold was increased. The group of scaffolds with pore sizes of 90-250 µm showed better cell proliferation and ECM production. These results demonstrated that the compressive strength of the scaffold was improved while the scaffold had pore sizes in the range 90-250 µm and good cell interconnectivity. Suitable space in the scaffold for cell viability is a key factor for cell metabolism. Copyright © 2014 John Wiley & Sons, Ltd.

Polymeric scaffolds in tissue engineering: a literature review

“…Pore architecture, including pore size, porosity, pore wall architecture, and pore interconnectivity, is the feature that is highly controllable in polymers. From reviewed papers, 10 articles evaluated following features on behavior of various cell types . Two Studies by Pamula group have shown high degree of osteoblast infiltration and proliferation in PLGA scaffolds with pore size of 400–600 μm and porosity of around 83% and 88% .…”

“…In particular, they showed high osteoblast proliferation on both surface and inside the scaffolds with larger pore size (600 μm), whereas in PLGA with smaller pores (40 μm) fewer cells were observed only on the surface of scaffolds . Similarly, Kim et al showed that PLGA scaffolds with pore size of around 410 μm supported more neural cell, human nucleus pulposus cell, adhesion as well as ECM production . Vaquette et al fabricated PCL scaffold to create scaffolds with different pore size ranges (5–20 µm).…”

Hybrid scaffolds based on PLGA and silk for bone tissue engineering

“…Fabrication of pristine PLGA scaffolds was achieved by following previously described procedures (Kim et al ., ; Ju et al ., ). Specifically, the lactide:glycolide ratio in PLGA was chosen as 75:25, because this combination was found to stably retain the 3D microporous morphology and had a fast in vivo degradation (Chant et al ., 1999; Wang et al ., ).…”

Exosome mediated transfer of miRNA‐140 promotes enhanced chondrogenic differentiation of bone marrow stem cells for enhanced cartilage repair and regeneration

“…Cultured media was removed and washed one time with PBS and then the staining was performed. All the samples were observed by inverted research microscope TE2000‐U (Nikon, Japan) 32 …”