Enzymatically crosslinked poly(2-alkyl-2-oxazoline) networks for 3D cell culture

A high-performance hydrogel was synthesized by a facile dual dynamic crosslinking strategy that showed injectability, cytocompatibility, broadly tunable mechanical properties and the potential for repair of load-bearing tissues.

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The Combined Effects of Co-Culture and Substrate Mechanics on 3D Tumor Spheroid Formation within Microgels Prepared via Flow-Focusing Microfluidic Fabrication

Pharmaceutics ◽

10.3390/pharmaceutics10040229 ◽

2018 ◽

Vol 10 (4) ◽

pp. 229 ◽

Cited By ~ 11

Author(s):

Dongjin Lee ◽

Chaenyung Cha

Keyword(s):

Mechanical Properties ◽

Cell Culture ◽

Microfluidic Device ◽

3D Cell Culture ◽

Breast Adenocarcinoma ◽

Adherent Cell ◽

Flow Focusing ◽

Spheroid Formation ◽

3D Scaffold ◽

Tumor Spheroids

Tumor spheroids are considered a valuable three dimensional (3D) tissue model to study various aspects of tumor physiology for biomedical applications such as tissue engineering and drug screening as well as basic scientific endeavors, as several cell types can efficiently form spheroids by themselves in both suspension and adherent cell cultures. However, it is more desirable to utilize a 3D scaffold with tunable properties to create more physiologically relevant tumor spheroids as well as optimize their formation. In this study, bioactive spherical microgels supporting 3D cell culture are fabricated by a flow-focusing microfluidic device. Uniform-sized aqueous droplets of gel precursor solution dispersed with cells generated by the microfluidic device are photocrosslinked to fabricate cell-laden microgels. Their mechanical properties are controlled by the concentration of gel-forming polymer. Using breast adenocarcinoma cells, MCF-7, the effect of mechanical properties of microgels on their proliferation and the eventual spheroid formation was explored. Furthermore, the tumor cells are co-cultured with macrophages of fibroblasts, which are known to play a prominent role in tumor physiology, within the microgels to explore their role in spheroid formation. Taken together, the results from this study provide the design strategy for creating tumor spheroids utilizing mechanically-tunable microgels as 3D cell culture platform.

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Lipodendriplexes mediated enhanced gene delivery: a cellular to pre-clinical investigation

Scientific Reports ◽

10.1038/s41598-020-78123-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Imran Tariq ◽

Muhammad Yasir Ali ◽

Muhammad Farhan Sohail ◽

Muhammad Umair Amin ◽

Sajid Ali ◽

...

Keyword(s):

Cell Culture ◽

Gene Delivery ◽

Cell Viability ◽

3D Cell Culture ◽

Serum Biochemistry ◽

Cellular Protein ◽

Ros Generation ◽

Gfp Expression

AbstractClinical success of effective gene therapy is mainly hampered by the insufficiency of safe and efficient internalization of a transgene to the targeted cellular site. Therefore, the development of a safe and efficient nanocarrier system is one of the fundamental challenges to transfer the therapeutic genes to the diseased cells. Polyamidoamine (PAMAM) dendrimer has been used as an efficient non-viral gene vector (dendriplexes) but the toxicity and unusual biodistribution induced by the terminal amino groups (–NH2) limit its in vivo applications. Hence, a state of the art lipid modification with PAMAM based gene carrier (lipodendriplexes) was planned to investigate theirs in vitro (2D and 3D cell culture) and in vivo behaviour. In vitro pDNA transfection, lactate dehydrogenase (LDH) release, reactive oxygen species (ROS) generation, cellular protein contents, live/dead staining and apoptosis were studied in 2D cell culture of HEK-293 cells while GFP transfection, 3D cell viability and live/dead staining of spheroids were performed in its 3D cell culture. Acute toxicity studies including organ to body index ratio, hematological parameters, serum biochemistry, histopathological profiles and in vivo transgene expression were assessed in female BALB/c mice. The results suggested that, in comparison to dendriplexes the lipodendriplexes exhibited significant improvement of pDNA transfection (p < 0.001) with lower LDH release (p < 0.01) and ROS generation (p < 0.05). A substantially higher cellular protein content (p < 0.01) and cell viability were also observed in 2D culture. A strong GFP expression with an improved cell viability profile (p < 0.05) was indicated in lipodendriplexes treated 3D spheroids. In vivo archives showed the superiority of lipid-modified nanocarrier system, depicted a significant increase in green fluorescent protein (GFP) expression in the lungs (p < 0.01), heart (p < 0.001), liver (p < 0.001) and kidneys (p < 0.001) with improved serum biochemistry and hematological profile as compared to unmodified dendriplexes. No tissue necrosis was evident in the animal groups treated with lipid-shielded molecules. Therefore, a non-covalent conjugation of lipids with PAMAM based carrier system could be considered as a promising approach for an efficient and biocompatible gene delivery system.

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Fabrication of Chitosan Nanofibers Scaffolds with Small Amount Gelatin for Enhanced Cell Viability

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.749.220 ◽

2015 ◽

Vol 749 ◽

pp. 220-224 ◽

Cited By ~ 1

Author(s):

Min Sup Kim ◽

Sang Jun Park ◽

Bon Kang Gu ◽

Chun Ho Kim

Keyword(s):

Mechanical Properties ◽

Cell Culture ◽

Cell Viability ◽

Dermal Fibroblast ◽

Fibroblast Cell ◽

Biological Properties ◽

Human Dermal Fibroblast ◽

Initial Contact ◽

Initial Contact Angle ◽

Contact Angle Analysis

Chitosan and gelatin has attracted considerable interest owing to its advantageous biological properties such as excellent biocompatibility, biodegradation, and non-toxic properties. In this paper, we investigated the potential of chitosan/gelatin (Chi-Gel) nanofibers mat with enhanced cell viability for use as cell culture scaffolds. The surface morphology, mechanical properties, and initial contact angle analysis of Chi-Gel nanofibers mat were evaluated. The proliferation of human dermal fibroblast cell (HDFs) on Chi-Gel nanofibers mat was found to be approximately 20% higher than the pure chitosan nanofibers mat after 7 days of culture. These results suggest that the Chi-Gel nanofibers mat has great potential for use tissue engineering applications.

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Autophagy (A) inhibition to enhance combined immunotherapy (I) and anti-EGFR treatment (E) in colorectal cancer (CRC).

Journal of Clinical Oncology ◽

10.1200/jco.2017.35.15_suppl.e14554 ◽

2017 ◽

Vol 35 (15_suppl) ◽

pp. e14554-e14554

Author(s):

Michalis Karamouzis ◽

Evangelos Koustas ◽

Chrysovalantou Mihailidou ◽

Dimitrios Schizas ◽

Athanasios G. Papavassiliou

Keyword(s):

Colorectal Cancer ◽

Cell Culture ◽

Cell Viability ◽

Caspase 3 ◽

Apoptotic Cell ◽

3D Cell Culture ◽

Protein Levels ◽

Promising Treatment ◽

Matrigel Matrix ◽

Combined Immunotherapy

e14554 Background: Resistance to E impairs survival of metastatic CRC (mCRC) patients. The aim of this study is to assess the preclinical activity of triple inhibition of E, I and A in CRC. Methods: RKO and Colo-205 cell lines were treated with E [cetuximab (C) / panitamumab (P)] and/or I [pembrolizumab (PE) or nivolumab (NI) with/without ipilimumab (IPI)] and/or autophagy inhibitor 3-Methyladenine (3-MA). Phosphorylated EGFR (pEGFR), p62 (SQSTM1), MAP1LC3 (LC3B) and PARP protein levels were detected by Western blotting. Cell viability was determined by MTT Assay. Tumor volumes were determined from 3D cell culture on Corning Matrigel Matrix as well as the apoptotic cell death. Results: E+I combination compared to E alone decreased pEGFR and increased A activation through p62 downregulation and LC3II activation. Similar results were shown for cell viability/apoptosis. Cells were also treated with C or P combined with I plus 3-MA. Triple inhibition suppresses EGFR and blocks A. Compared to E+I, triple inhibition reduced more cell growth/viability. Caspase-3 activity was increased as well as proportion of apoptotic cells (Table). Conclusions: Τhese results indicate that the combinatorial inhibition of A, E and I represents a promising treatment strategy in mCRC that needs further testing. [Table: see text]

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Polysaccharide-based hydrogels with tunable composition as 3D cell culture systems

The International Journal of Artificial Organs ◽

10.5301/ijao.5000667 ◽

2018 ◽

Vol 41 (4) ◽

pp. 213-222

Author(s):

Roberta Gentilini ◽

Fabiola Munarin ◽

Nora Bloise ◽

Eleonora Secchi ◽

Livia Visai ◽

...

Keyword(s):

Cell Culture ◽

Cell Viability ◽

Viscoelastic Properties ◽

3D Cell Culture ◽

Promote Cell Proliferation ◽

Culture Systems ◽

Weight Variation ◽

Cell Culture Systems ◽

Initial Ph

Background: To date, cell cultures have been created either on 2-dimensional (2D) polystyrene surfaces or in 3-dimensional (3D) systems, which do not offer a controlled chemical composition, and which lack the soft environment encountered in vivo and the chemical stimuli that promote cell proliferation and allow complex cellular behavior. In this study, pectin-based hydrogels were developed and are proposed as versatile cell culture systems. Methods: Pectin-based hydrogels were produced by internally crosslinking pectin with calcium carbonate at different initial pH, aiming to control crosslinking kinetics and degree. Additionally, glucose and glutamine were added as additives, and their effects on the viscoelastic properties of the hydrogels and on cell viability were investigated. Results: Pectin hydrogels showed in high cell viability and shear-thinning behavior. Independently of hydrogel composition, an initial swelling was observed, followed by a low percentage of weight variation and a steady-state stage. The addition of glucose and glutamine to pectin-based hydrogels rendered higher cell viability up to 90%-98% after 1 hour of incubation, and these hydrogels were maintained for up to 7 days of culture, yet no effect on viscoelastic properties was detected. Conclusions: Pectin-based hydrogels that offer tunable composition were developed successfully. They are envisioned as synthetic extracellular matrix (ECM) either to study complex cellular behaviors or to be applied as tissue engineering substitutes.

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Cell viability assessment using the Alamar blue assay: A comparison of 2D and 3D cell culture models

Toxicology in Vitro ◽

10.1016/j.tiv.2014.09.014 ◽

2015 ◽

Vol 29 (1) ◽

pp. 124-131 ◽

Cited By ~ 83

Author(s):

F. Bonnier ◽

M.E. Keating ◽

T.P. Wróbel ◽

K. Majzner ◽

M. Baranska ◽

...

Keyword(s):

Cell Culture ◽

Cell Viability ◽

3D Cell Culture ◽

Alamar Blue Assay ◽

Alamar Blue ◽

Viability Assessment ◽

Culture Models ◽

2D And 3D ◽

Cell Culture Models

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Viscoelastic Oxidized Alginates with Reversible Imine Type Crosslinks: Self-Healing, Injectable, and Bioprintable Hydrogels

Gels ◽

10.3390/gels4040085 ◽

2018 ◽

Vol 4 (4) ◽

pp. 85 ◽

Cited By ~ 22

Author(s):

Shahzad Hafeez ◽

Huey Ooi ◽

Francis Morgan ◽

Carlos Mota ◽

Monica Dettin ◽

...

Keyword(s):

Mechanical Properties ◽

Cell Culture ◽

Viscoelastic Properties ◽

Soft Tissues ◽

3D Cell Culture ◽

Cell Delivery ◽

Self Healing ◽

Marked Influence ◽

Cell Culture Systems ◽

Multiscale Structures

Bioprinting techniques allow for the recreation of 3D tissue-like structures. By deposition of hydrogels combined with cells (bioinks) in a spatially controlled way, one can create complex and multiscale structures. Despite this promise, the ability to deposit customizable cell-laden structures for soft tissues is still limited. Traditionally, bioprinting relies on hydrogels comprised of covalent or mostly static crosslinks. Yet, soft tissues and the extracellular matrix (ECM) possess viscoelastic properties, which can be more appropriately mimicked with hydrogels containing reversible crosslinks. In this study, we have investigated aldehyde containing oxidized alginate (ox-alg), combined with different cross-linkers, to develop a small library of viscoelastic, self-healing, and bioprintable hydrogels. By using distinctly different imine-type dynamic covalent chemistries (DCvC), (oxime, semicarbazone, and hydrazone), rational tuning of rheological and mechanical properties was possible. While all materials showed biocompatibility, we observed that the nature of imine type crosslink had a marked influence on hydrogel stiffness, viscoelasticity, self-healing, cell morphology, and printability. The semicarbazone and hydrazone crosslinks were found to be viscoelastic, self-healing, and printable—without the need for additional Ca2+ crosslinking—while also promoting the adhesion and spreading of fibroblasts. In contrast, the oxime cross-linked gels were found to be mostly elastic and showed neither self-healing, suitable printability, nor fibroblast spreading. The semicarbazone and hydrazone gels hold great potential as dynamic 3D cell culture systems, for therapeutics and cell delivery, and a newer generation of smart bioinks.

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Poly(glycerol sebacate) – a revolutionary biopolymer

Physical Sciences Reviews ◽

10.1515/psr-2020-0071 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Israd H. Jaafar ◽

Sabrina S. Jedlicka ◽

John P. Coulter

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

Cell Culture ◽

Surface Modification ◽

Mammalian Cell Culture ◽

Chemical Properties ◽

Tunable Mechanical Properties ◽

And Chemical Properties

Abstract Novel materials possessing physical, mechanical, and chemical properties similar to those found in vivo provide a potential platform for building artificial microenvironments for tissue engineering applications. Poly(glycerol sebacate) is one such material. It has tunable mechanical properties within the range of common tissue, and favorable cell response without surface modification with adhesive ligands, and biodegradability. In this chapter, an overview of the material is presented, focusing on synthesis, characterization, microfabrication, use as a substrate in in vitro mammalian cell culture, and degradation characteristics.

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Improved cell viability for large-scale biofabrication with photo-crosslinkable hydrogel systems through a dual-photoinitiator approach

Biomaterials Science ◽

10.1039/c9bm01347d ◽

2020 ◽

Vol 8 (1) ◽

pp. 450-461 ◽

Cited By ~ 4

Author(s):

Win Tun Han ◽

Taesik Jang ◽

Shengyang Chen ◽

Lydia Shi Hui Chong ◽

Hyun-Do Jung ◽

...

Keyword(s):

Mechanical Properties ◽

Cell Viability ◽

Large Scale ◽

High Cell ◽

Activation Kinetics ◽

Concurrent Use

Through concurrent use of photoinitiators with different activation kinetics, a hydrogel crosslinking system exhibited efficient crosslinking properties and desired mechanical properties with high cell viability.

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