Investigation of the Regenerative Potential of Human Bone Marrow Stem Cell-Seeded Polycaprolactone Bone Scaffolds, Fabricated Using Pneumatic Microextrusion Process

2021 ◽  
Author(s):  
Logan Lawrence ◽  
James B. Day ◽  
Pier Paolo Claudio ◽  
Roozbeh (Ross) Salary
Keyword(s):  
Stem Cell ◽  
Structural Integrity ◽  
Biological Tissues ◽  
Direct Write ◽  
Osteosarcoma Cell ◽  
Bone Scaffolds ◽  
Depth Analysis ◽  
Cell Scaffold ◽  
Material Process

Abstract Pneumatic MicroExtrusion (PME) is a direct-write additive manufacturing process, which has emerged as a robust, high-resolution method for the fabrication of a broad spectrum of biological tissues and organs. However, the PME process is intrinsically complex, governed by bio-physio-chemical phenomena as well as material-process interactions. Hence, investigation of the influence of consequential factors on bone scaffold fabrication as well as investigation of cell-scaffold interactions would be an inevitable need. The objective of the work is to investigate the biocompatibility as well as the histological properties of PME-fabricated porous bone scaffolds, composed of polycaprolactone (PCL). To achieve this objective, a media extraction of the scaffold material was tested for cytostatic or cytotoxic activity with the aim to: (i) assess the fabricated scaffolds’ feasibility of use in regenerative medicine, and (ii) determine their structural integrity in a modelled in-vivo environment. In addition, the scaffolds were inoculated with an established osteosarcoma cell line (SAOS-2) and cultured for seven days to investigate the scaffold architecture and cell integration potential. A histological examination was performed on the seeded scaffolds for further in-depth analysis of cell-scaffold interaction. Overall, the results of this study pave the way for future investigation of stem cell incorporation into PME-fabricated PCL scaffolds toward the treatment of osseous fractures and defects.

Pneumatic Microextrusion-Based Additive Biofabrication of Polycaprolactone Bone Scaffolds: Part II – Investigation of the Influence of Polymer Flow Parameters

2021 ◽  
Author(s):  
Mohan Yu ◽  
Logan Lawrence ◽  
Pier Paolo Claudio ◽  
James B. Day ◽  
Roozbeh (Ross) Salary
Keyword(s):  
Mechanical Performance ◽  
Research Work ◽  
Biological Tissues ◽  
Direct Write ◽  
Bone Scaffolds ◽  
Flow Parameters ◽  
Material Deposition ◽  
Flow Pressure ◽  
Physical Phenomena ◽  
Head Temperature

Abstract Pneumatic micro-extrusion (PME), a direct-write additive manufacturing process, has emerged as a high-resolution method for the fabrication of a broad range of biological tissues and organs. However, the PME process is intrinsically complex, governed by complex physical phenomena. Hence, investigation of the effects of consequential parameters would be an inevitable need. The goal of this research work is to fabricate biocompatible, porous bone tissue scaffolds for the treatment of osseous fractures, defects, and eventually diseases. In pursuit of this goal, the objective of this study is to investigate the influence of material deposition factors — i.e., (i) deposition head temperature, (ii) flow pressure, and (iii) infill pattern — on the mechanical performance of PME-fabricated bone scaffolds. It was observed that the deposition head temperature as well as the flow pressure significantly affected scaffold diameter (unlike scaffold height). In addition, material deposition rate increased significantly as a result of an increase in the deposition temperature; this phenomenon stems from a reduction in Polycaprolactone (PCL) viscosity. Furthermore, there was a direct correlation between the amount of deposited mass and scaffold stiffness. Overall, the results of this study pave the way for future investigation of PME-deposited PCL scaffolds with optimal functional properties for incorporation of stem cells toward the treatment of osseous fractures and defects.

lncRNA, PVT-1, controls tumorigenesis and cancer stem-like phenotypes in osteosarcoma through PI3K/TSC2.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e23512-e23512
Author(s):  
Susan Tsang ◽  
Nino Carlo Rainusso ◽  
Jason Todd Yustein
Keyword(s):  
Stem Cell ◽  
Cancer Stem Cell ◽  
Cell Lines ◽  
Bone Cancer ◽  
High Rate ◽  
Osteosarcoma Cell ◽  
Self Renewal ◽  
Cell Phenotypes

e23512 Background: Osteosarcoma is the most common pediatric bone cancer and a key genetic characteristic of this particular malignancy is its complex karyotype. Specifically it has been reported that 40% of osteosarcoma patients’ present with 8q24 amplification. The presence of this specific amplification has been previously associated with a high rate of relapse and poor prognosis for osteosarcoma patients. Within this amplicon resides, a long non-coding RNA gene, PVT-1. Prior studies indicates that PVT-1 has pro-oncogenic properties however the function of PVT-1 in osteosarcoma is not well characterized. Methods: To understand PVT-1 copy number, Fluorescent In Situ Hybridization was performed on both osteosarcoma cell lines and osteosarcoma patient-derived xenografts. In addition the PVT-1 RNA level is elevated in a majority of osteosarcoma samples compared to normal bone. To test PVT-1 pro-oncogenic role in osteosarcoma, several functional assays were performed. Results: Our studies demonstrated that overexpression of PVT-1 in osteosarcoma cell lines promotes multiple tumorigenic behaviors including enhanced proliferation, migration, invasion and chemotherapeutic resistance to cisplatin. PVT-1’s ability to mediate metastasis and contribute to chemotherapeutic sensitivity is a shared phenotype of cancer stem cells. Based on this observation, we hypothesize targeting PVT-1 will reduce cancer stem-cell properties. Osteosarcoma lines with increased levels of PVT-1 exhibited higher expression of cancer stem cell genes: Nanog, SOX2, c-Myc, and Oct4 at both the transcriptomic and proteomic level. In Vitro and In Vivo self-renewal capacity studies showed enhanced osteosarcoma cell self-renewal in the PVT-1 overexpression cohort. Additional molecular studies were performed in order to gain additional insights into potential mechanism of action for PVT-1 including Reverse Phase Protein Array. Initial analysis suggest a role for PVT-1 in regulating the PI3K-AKT-TSC2 pathway. Conclusions: This suggests a potential oncogenic pathway in which PVT-1 enhances cancer stem cell phenotypes. On-going investigations are addressing potential PI3K/TSC2 pathway inhibitors, BEZ-2335 and LY3023414, which could be utilized to regulate PVT-1 mediated tumorigenic roles and cancer stem-like properties.

The Study of Collagen-HA Composite with Incorporated BMP as Bone Tissue Engineering Scaffold

2005 ◽  
Vol 288-289 ◽  
pp. 261-264 ◽  
Author(s):  
L.R. Liu ◽  
L.H. Zhang ◽  
F.J. Wang ◽  
Q.Q. Zhang
Keyword(s):  
Tissue Engineering ◽  
Stem Cell ◽  
Phase Separation ◽  
Mesenchymal Stem Cell ◽  
Chondroitin Sulfate ◽  
Cell Compatibility ◽  
Cell Scaffold ◽  
A Cell ◽  
Good Cell

Collagen-HA scaffolds were prepared by a phase-separation technique, cross-linked by formaldehyde or carbodiimide(EDC)/N-hydroxysuccinimide(NHS), which is also used to covalently attach chondroitin sulfate(CS) to the scaffold. BMP was incorporated into the scaffold by adsorption. The scaffolds were characterized by SEM and ESCA. Rat mesenchymal stem cell(MSCs) was seeded into the scaffold and cultured to form a cell/scaffold construct. The ectopic osteoinduction of the scaffolds were evaluated in vivo. The results show that the scaffolds are porous with three-dimensionality, have good cell compatibility and osteoinduction. Attachment of CS can improve the adhesion and differentiation of cells.

scholarly journals Scaffold-based 3D cellular models mimicking the heterogeneity of osteosarcoma stem cell niche

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Giada Bassi ◽  
Silvia Panseri ◽  
Samuele Maria Dozio ◽  
Monica Sandri ◽  
Elisabetta Campodoni ◽  
...  
Keyword(s):  
Cell Culture ◽  
Stem Cell ◽  
Stem Cell Niche ◽  
Drug Testing ◽  
Tumour Microenvironment ◽  
Osteosarcoma Cell ◽  
Cellular Models ◽  
Cell Niche

AbstractThe failure of the osteosarcoma conventional therapies leads to the growing need for novel therapeutic strategies. The lack of specificity for the Cancer Stem Cells (CSCs) population has been recently identified as the main limitation in the current therapies. Moreover, the traditional two-dimensional (2D) in vitro models, employed in the drug testing and screening as well as in the study of cell and molecular biology, are affected by a poor in vitro-in vivo translation ability. To overcome these limitations, this work provides two tumour engineering approaches as new tools to address osteosarcoma and improve therapy outcomes. In detail, two different hydroxyapatite-based bone-mimicking scaffolds were used to recapitulate aspects of the in vivo tumour microenvironment, focusing on CSCs niche. The biological performance of human osteosarcoma cell lines (MG63 and SAOS-2) and enriched-CSCs were deeply analysed in these complex cell culture models. The results highlight the fundamental role of the tumour microenvironment proving the mimicry of osteosarcoma stem cell niche by the use of CSCs together with the biomimetic scaffolds, compared to conventional 2D culture systems. These advanced 3D cell culture in vitro tumour models could improve the predictivity of preclinical studies and strongly enhance the clinical translation.

Monitoring stem cell migration in the nervous system by in vivo magnetic resonance imaging

2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S692-S692
Author(s):  
Mathias Hoehn ◽  
Uwe Himmelreich ◽  
Ralph Weber ◽  
Pedro Ramos-Cabrer ◽  
Susanne Wegener ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Nervous System ◽  
Stem Cell ◽  
Cell Migration ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Stem Cell Migration
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