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Spatiotemporal Control of Morphogen Delivery to Pattern Stem Cell Differentiation in Three-Dimensional Hydrogels.
O'Grady BJ, Balikov DA, Lippmann ES, Bellan LM
(2019) Curr Protoc Stem Cell Biol 51: e97
MeSH Terms: Cell Differentiation, Cells, Cultured, Hydrogels, Morphogenesis, Stem Cells, Tissue Engineering
Show Abstract · Added March 18, 2020
Morphogens are biological molecules that alter cellular identity and behavior across both space and time. During embryonic development, morphogen spatial localization can be confined to small volumes in a single tissue or permeate throughout an entire organism, and the temporal effects of morphogens can range from fractions of a second to several days. In most cases, morphogens are presented as a gradient to adjacent cells within tissues to pattern cell fate. As such, to appropriately model development and build representative multicellular architectures in vitro, it is vital to recapitulate these gradients during stem cell differentiation. However, the ability to control morphogen presentation within in vitro systems remains challenging. Here, we describe an innovative platform using channels patterned within thick, three-dimensional hydrogels that deliver multiple morphogens to embedded cells, thereby demonstrating exquisite control over both spatial and temporal variations in morphogen presentation. This generalizable approach should have broad utility for researchers interested in patterning in vitro tissue structures. © 2019 by John Wiley & Sons, Inc.
© 2019 John Wiley & Sons, Inc.
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6 MeSH Terms
iPSC-Derived Brain Endothelium Exhibits Stable, Long-Term Barrier Function in Perfused Hydrogel Scaffolds.
Faley SL, Neal EH, Wang JX, Bosworth AM, Weber CM, Balotin KM, Lippmann ES, Bellan LM
(2019) Stem Cell Reports 12: 474-487
MeSH Terms: Albumins, Blood-Brain Barrier, Brain, Cells, Cultured, Dextrans, Endothelial Cells, Endothelium, Fluorescein, Humans, Hydrogels, Induced Pluripotent Stem Cells, Microvessels
Show Abstract · Added March 18, 2020
There is a profound need for functional, biomimetic in vitro tissue constructs of the human blood-brain barrier and neurovascular unit (NVU) to model diseases and identify therapeutic interventions. Here, we show that induced pluripotent stem cell (iPSC)-derived human brain microvascular endothelial cells (BMECs) exhibit robust barrier functionality when cultured in 3D channels within gelatin hydrogels. We determined that BMECs cultured in 3D under perfusion conditions were 10-100 times less permeable to sodium fluorescein, 3 kDa dextran, and albumin relative to human umbilical vein endothelial cell and human dermal microvascular endothelial cell controls, and the BMECs maintained barrier function for up to 21 days. Analysis of cell-cell junctions revealed expression patterns supporting barrier formation. Finally, efflux transporter activity was maintained over 3 weeks of perfused culture. Taken together, this work lays the foundation for development of a representative 3D in vitro model of the human NVU constructed from iPSCs.
Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.
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Substrate Elasticity Governs Differentiation of Renal Tubule Cells in Prolonged Culture.
Love HD, Ao M, Jorgensen S, Swearingen L, Ferrell N, Evans R, Gewin L, Harris RC, Zent R, Roy S, Fissell WH
(2019) Tissue Eng Part A 25: 1013-1022
MeSH Terms: Animals, Aquaporins, Cell Differentiation, Cell Proliferation, Cell Shape, Cells, Cultured, Elasticity, Humans, Hydrogels, Kidney Tubules, Mice, Receptors, Transforming Growth Factor beta, Signal Transduction, Sodium-Hydrogen Exchanger 3, Transforming Growth Factor beta
Show Abstract · Added March 26, 2019
IMPACT STATEMENT - Successful clinical tissue engineering requires functional fidelity of the cultured cell to its counterpart, but this has been elusive in renal tissue engineering. Typically, renal proximal tubule cells in culture have a flattened morphology and do not express key transporters essential to their function. In this article, we show for the first time that substrate mechanical properties dictate differentiation of cultured renal proximal tubule cells. Remarkably, this effect was only discernable after 4 weeks in culture, longer than usually reported for this cell type. These results demonstrate a new tunable parameter to optimize cell differentiation in renal tissue engineering.
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15 MeSH Terms
Supplementation of p40, a Lactobacillus rhamnosus GG-derived protein, in early life promotes epidermal growth factor receptor-dependent intestinal development and long-term health outcomes.
Shen X, Liu L, Peek RM, Acra SA, Moore DJ, Wilson KT, He F, Polk DB, Yan F
(2018) Mucosal Immunol 11: 1316-1328
MeSH Terms: Animals, Bacterial Proteins, Cell Differentiation, Cell Proliferation, Epithelial Cells, ErbB Receptors, Female, Hydrogels, Immunity, Innate, Immunoglobulin A, Intestinal Mucosa, Lactobacillus rhamnosus, Mice, Mice, Inbred C57BL, Probiotics, T-Lymphocytes, Regulatory, Tight Junctions, Time, Transcriptional Activation
Show Abstract · Added June 8, 2018
The beneficial effects of the gut microbiota on growth in early life are well known. However, knowledge about the mechanisms underlying regulating intestinal development by the microbiota is limited. p40, a Lactobacillus rhamnosus GG-derived protein, transactivates epidermal growth factor receptor (EGFR) in intestinal epithelial cells for protecting the intestinal epithelium against injury and inflammation. Here, we developed p40-containing pectin/zein hydrogels for targeted delivery of p40 to the small intestine and the colon. Treatment with p40-containing hydrogels from postnatal day 2 to 21 significantly enhanced bodyweight gain prior to weaning and functional maturation of the intestine, including intestinal epithelial cell proliferation, differentiation, and tight junction formation, and IgA production in early life in wild-type mice. These p40-induced effects were abolished in mice with specific deletion of EGFR in intestinal epithelial cells, suggesting that transactivation of EGFR in intestinal epithelial cells may mediate p40-regulated intestinal development. Furthermore, neonatal p40 treatment reduced the susceptibility to intestinal injury and colitis and promoted protective immune responses, including IgA production and differentiation of regulatory T cells, in adult mice. These findings reveal novel roles of neonatal supplementation of probiotic-derived factors in promoting EGFR-mediated maturation of intestinal functions and innate immunity, which likely promote long-term beneficial outcomes.
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2 Members
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19 MeSH Terms
A Customizable, Low-Cost Perfusion System for Sustaining Tissue Constructs.
O'Grady BJ, Wang JX, Faley SL, Balikov DA, Lippmann ES, Bellan LM
(2018) SLAS Technol 23: 592-598
MeSH Terms: Costs and Cost Analysis, Hydrogels, Perfusion, Tissue Culture Techniques, Tissue Engineering
Show Abstract · Added March 18, 2020
The fabrication of engineered vascularized tissues and organs requiring sustained, controlled perfusion has been facilitated by the development of several pump systems. Currently, researchers in the field of tissue engineering require the use of pump systems that are in general large, expensive, and generically designed. Overall, these pumps often fail to meet the unique demands of perfusing clinically useful tissue constructs. Here, we describe a pumping platform that overcomes these limitations and enables scalable perfusion of large, three-dimensional hydrogels. We demonstrate the ability to perfuse multiple separate channels inside hydrogel slabs using a preprogrammed schedule that dictates pumping speed and time. The use of this pump system to perfuse channels in large-scale engineered tissue scaffolds sustained cell viability over several weeks.
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Pathways to clinical CLARITY: volumetric analysis of irregular, soft, and heterogeneous tissues in development and disease.
Hsueh B, Burns VM, Pauerstein P, Holzem K, Ye L, Engberg K, Wang AC, Gu X, Chakravarthy H, Arda HE, Charville G, Vogel H, Efimov IR, Kim S, Deisseroth K
(2017) Sci Rep 7: 5899
MeSH Terms: Animals, Disease, Female, Humans, Hydrogels, Imaging, Three-Dimensional, Mice, Inbred C57BL, Neural Crest, Neurosecretory Systems, Organogenesis, Pancreas
Show Abstract · Added October 31, 2017
Three-dimensional tissue-structural relationships are not well captured by typical thin-section histology, posing challenges for the study of tissue physiology and pathology. Moreover, while recent progress has been made with intact methods for clearing, labeling, and imaging whole organs such as the mature brain, these approaches are generally unsuitable for soft, irregular, and heterogeneous tissues that account for the vast majority of clinical samples and biopsies. Here we develop a biphasic hydrogel methodology, which along with automated analysis, provides for high-throughput quantitative volumetric interrogation of spatially-irregular and friable tissue structures. We validate and apply this approach in the examination of a variety of developing and diseased tissues, with specific focus on the dynamics of normal and pathological pancreatic innervation and development, including in clinical samples. Quantitative advantages of the intact-tissue approach were demonstrated compared to conventional thin-section histology, pointing to broad applications in both research and clinical settings.
1 Communities
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11 MeSH Terms
Multiresponsive Nanogels for Targeted Anticancer Drug Delivery.
Zhang Q, Colazo J, Berg D, Mugo SM, Serpe MJ
(2017) Mol Pharm 14: 2624-2628
MeSH Terms: Antineoplastic Agents, Cell Survival, Concanavalin A, Doxorubicin, Drug Carriers, Hep G2 Cells, Humans, Hydrogen-Ion Concentration, Nanogels, Nanoparticles, Polyethylene Glycols, Polyethyleneimine, Polymers
Show Abstract · Added November 7, 2019
Nanogels with a biomolecular coating (biocoating) were shown to be capable of triggered delivery of anticancer drug Doxorubicin. The biocoating was formed utilizing binding between glycogen and the tetra-functional lectin Concanavalin A, which can be triggered to disassemble (and release) upon exposure to glucose and changes in solution pH. We also show the nanogel's thermoresponsivity can be used to accelerate Doxorubicin release. Moreover, we showed that transferrin immobilized on the nanogel surface could accelerate nanogel uptake by cancer cells. In these experiments, we showed that Doxorubicin was able to be released to the nucleus of human liver cancer cell line (HepG2) within 3 h. Doxorubicin-loaded nanogels exhibit a strong growth inhibition ability toward HepG2. This investigation showcases how nanogel design and chemistry can be tuned to achieve useful biomedical applications.
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13 MeSH Terms
Reactive Oxygen Species Shielding Hydrogel for the Delivery of Adherent and Nonadherent Therapeutic Cell Types.
Dollinger BR, Gupta MK, Martin JR, Duvall CL
(2017) Tissue Eng Part A 23: 1120-1131
MeSH Terms: Animals, Cell Adhesion, Cell Count, Cell Death, Cytoprotection, Humans, Hydrogels, Hydrogen Peroxide, Mesenchymal Stem Cell Transplantation, Mesenchymal Stem Cells, Mice, Polymers, Reactive Oxygen Species, Rheology
Show Abstract · Added March 14, 2018
Cell therapies suffer from poor survival post-transplant due to placement into hostile implant sites characterized by host immune response and innate production of high levels of reactive oxygen species (ROS). We hypothesized that cellular encapsulation within an injectable, antioxidant hydrogel would improve viability of cells exposed to high oxidative stress. To test this hypothesis, we applied a dual thermo- and ROS-responsive hydrogel comprising the ABC triblock polymer poly[(propylene sulfide)-block-(N,N-dimethyl acrylamide)-block-(N-isopropylacrylamide)] (PPS-b-PDMA-b-PNIPAAM, PDN). The PPS chemistry reacts irreversibly with ROS such as hydrogen peroxide (HO), imparting inherent antioxidant properties to the system. Here, PDN hydrogels were successfully integrated with type 1 collagen to form ROS-protective, composite hydrogels amenable to spreading and growth of adherent cell types such as mesenchymal stem cells (MSCs). It was also shown that, using a control hydrogel substituting nonreactive polycaprolactone in place of PPS, the ROS-reactive PPS chemistry is directly responsible for PDN hydrogel cytoprotection of both MSCs and insulin-producing β-cell pseudo-islets against HO toxicity. In sum, these results establish the potential of cytoprotective, thermogelling PDN biomaterials for injectable delivery of cell therapies.
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14 MeSH Terms
Enhanced Spatially Resolved Proteomics Using On-Tissue Hydrogel-Mediated Protein Digestion.
Rizzo DG, Prentice BM, Moore JL, Norris JL, Caprioli RM
(2017) Anal Chem 89: 2948-2955
MeSH Terms: Acrylic Resins, Animals, Cerebellum, Chromatography, High Pressure Liquid, Hydrogels, Liver, Proteins, Proteolysis, Rats, Tandem Mass Spectrometry, Trypsin
Show Abstract · Added March 10, 2017
The identification of proteins from tissue specimens is a challenging area of biological research. Many current techniques for identification forfeit some level of spatial information during the sample preparation process. Recently, hydrogel technologies have been developed that perform spatially localized protein extraction and digestion prior to downstream proteomic analysis. Regiospecific protein identifications acquired using this approach have thus far been limited to 1-2 mm diameter areas. The need to target smaller populations of cells with this technology necessitates the production of smaller diameter hydrogels. Herein, we demonstrate hydrogel fabrication processes that allow hydrogel applications down to a diameter of ∼260 μm, approximately 1/15 of the area of previous approaches. Parameters such as the percent polyacrylamide used in hydrogel construction as well as the concentration of trypsin with which the hydrogel is loaded are investigated to maximize the number of protein identifications from subsequent liquid chromatography tandem MS (LC-MS/MS) analysis of hydrogel extracts. An 18% polyacrylamide concentration is shown to provide for a more rigid polymer network than the conventional 7.5% polyacrylamide concentration and supports the fabrication of individual hydrogels using the small punch biopsies. Over 600 protein identifications are still achieved at the smallest hydrogel diameters of 260 μm. The utility of these small hydrogels is demonstrated through the analysis of sub regions of a rat cerebellum tissue section. While over 900 protein identifications are made from each hydrogel, approximately 20% of the proteins identified are unique to each of the two regions, highlighting the importance of targeting tissue subtypes to accurately characterize tissue biology. These newly improved methods to the hydrogel process will allow researchers to target smaller biological features for robust spatially localized proteomic analyses.
1 Communities
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11 MeSH Terms
Investigating the Structure of Multicomponent Gel-Phase Lipid Bilayers.
Hartkamp R, Moore TC, Iacovella CR, Thompson MA, Bulsara PA, Moore DJ, McCabe C
(2016) Biophys J 111: 813-823
MeSH Terms: Gels, Hydrogen Bonding, Lipid Bilayers, Models, Molecular, Molecular Conformation, Water
Show Abstract · Added May 3, 2017
Single- and multicomponent lipid bilayers of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), 1,2-distearoyl-sn-glycero-3-phosphatidylcholine (DSPC), isostearyl isostearate, and heptadecanoyl heptadecanoate in the gel phase are studied via molecular dynamics simulations. It is shown that the structural properties of multicomponent bilayers can deviate strongly from the structures of their single-component counterparts. Specifically, the lipid mixtures are shown to adopt a compact packing by offsetting the positioning depths at which different lipid species are located in the bilayer. This packing mechanism affects the area per lipid, the bilayer height, and the chain tilt angles and has important consequences for other bilayer properties, such as interfacial hydrogen bonding and bilayer permeability. In particular, the simulations suggest that bilayers containing isostearyl isostearate or heptadecanoyl heptadecanoate are less permeable than pure 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine or DSPC bilayers. Furthermore, hydrogen-bond analysis shows that the residence times of lipid-water hydrogen bonds depend strongly on the bilayer composition, with longer residence times for bilayers that have a higher DSPC content. The findings illustrate and explain the fundamental differences between the properties of single- and multicomponent bilayers.
Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.
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6 MeSH Terms