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Gleeson JP, Brayden DJ, Ryan SM. Evaluation of PepT1 transport of food-derived antihypertensive peptides, Ile-Pro-Pro and Leu-Lys-Pro using in vitro, ex vivo and in vivo transport models. Eur J Pharm Biopharm 2017; 115:276-284. [PMID: 28315445 DOI: 10.1016/j.ejpb.2017.03.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 03/08/2017] [Accepted: 03/11/2017] [Indexed: 11/18/2022]
Abstract
Ile-Pro-Pro (IPP) and Leu-Lys-Pro (LKP) are food-derived antihypertensive peptides which inhibit angiotensin-converting enzyme (ACE) and may have potential to attenuate hypertension. There is debate over their mechanism of uptake across small intestinal epithelia, but paracellular and PepT1 carrier-mediated uptake are thought to be important routes. The aim of this study was to determine their routes of intestinal permeability using in vitro, ex vivo and in vivo intestinal models. The presence of an apical side pH of 6.5 (mimicking the intestinal acidic microclimate) and of Gly-Sar (a high affinity competitive inhibitor and substrate for PepT1) were tested on the transepithelial apical to basolateral (A to B) transport of [3H]-IPP and [3H]-LKP across filter-grown Caco-2 monolayers in vitro and rat jejunal mucosae ex vivo. A buffer pH of 6.5 on the apical side enabled Gly-Sar to reduce the apparent permeability (Papp) of [3H]-IPP and [3H]-LKP, but this inhibition was not evident at an apical buffer pH of 7.4. Gly-Sar reduced the Papp across isolated jejunal mucosae and the area under the curve (AUC) in intra-jejunal instillations when the apical/luminal buffer pH was either 7.4 or 6.5. However, the jejunal surface acidic pH was maintained in rat jejunal tissue even when the apical side buffer pH was 7.4 due to the presence of the microclimate which is not present in monolayers. PepT1 expression was confirmed by immunofluorescence on monolayers and brush border of rat jejunal tissue. This data suggest that IPP and LKP are highly permeable and cross small intestinal epithelia in part by the PepT1 transporter, with an additional contribution from the paracellular route.
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Affiliation(s)
- John P Gleeson
- UCD School of Veterinary Medicine and UCD Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - David J Brayden
- UCD School of Veterinary Medicine and UCD Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Sinéad M Ryan
- UCD School of Veterinary Medicine and UCD Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland.
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402
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Integration concepts for multi-organ chips: how to maintain flexibility?! Future Sci OA 2017; 3:FSO180. [PMID: 28670472 PMCID: PMC5481865 DOI: 10.4155/fsoa-2016-0092] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 02/01/2017] [Indexed: 12/28/2022] Open
Abstract
Multi-organ platforms have an enormous potential to lead to a paradigm shift in a multitude of research domains including drug development, toxicological screening, personalized medicine as well as disease modeling. Integrating multiple organ–tissues into one microfluidic circulation merges the advantages of cell lines (human genetic background) and animal models (complex physiology) and enables the creation of more in vivo-like in vitro models. In recent years, a variety of design concepts for multi-organ platforms have been introduced, categorizable into static, semistatic and flexible systems. The most promising approach seems to be flexible interconnection of single-organ platforms to application-specific multi-organ systems. This perspective elucidates the concept of ‘mix-and-match’ toolboxes and discusses the numerous advantages compared with static/semistatic platforms as well as remaining challenges. ‘Organs-on-a-chip’ are platforms accommodating organ-specific human tissues in microscale 3D chambers with physiologically relevant structure. Broken down to the basic building blocks but simultaneously mimicking essential organ functions, these sophisticated biochips can help reduce the need for animal models in drug development, toxicity screening and basic research. However, to simulate a drug's journey through the human body, it is necessary to consider how a combination of organs responds to a given drug. In this perspective, concepts of realizing such ‘multi-organ platforms’ and the need for ‘mix-and-match’ toolboxes, which contain a range of single-organ units interconnected in individual, application-specific configurations, are discussed.
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403
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A microengineered collagen scaffold for generating a polarized crypt-villus architecture of human small intestinal epithelium. Biomaterials 2017; 128:44-55. [PMID: 28288348 DOI: 10.1016/j.biomaterials.2017.03.005] [Citation(s) in RCA: 209] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/04/2017] [Accepted: 03/04/2017] [Indexed: 02/06/2023]
Abstract
The human small intestinal epithelium possesses a distinct crypt-villus architecture and tissue polarity in which proliferative cells reside inside crypts while differentiated cells are localized to the villi. Indirect evidence has shown that the processes of differentiation and migration are driven in part by biochemical gradients of factors that specify the polarity of these cellular compartments; however, direct evidence for gradient-driven patterning of this in vivo architecture has been hampered by limitations of the in vitro systems available. Enteroid cultures are a powerful in vitro system; nevertheless, these spheroidal structures fail to replicate the architecture and lineage compartmentalization found in vivo, and are not easily subjected to gradients of growth factors. In the current work, we report the development of a micropatterned collagen scaffold with suitable extracellular matrix and stiffness to generate an in vitro self-renewing human small intestinal epithelium that replicates key features of the in vivo small intestine: a crypt-villus architecture with appropriate cell-lineage compartmentalization and an open and accessible luminal surface. Chemical gradients applied to the crypt-villus axis promoted the creation of a stem/progenitor-cell zone and supported cell migration along the crypt-villus axis. This new approach combining microengineered scaffolds, biophysical cues and chemical gradients to control the intestinal epithelium ex vivo can serve as a physiologically relevant mimic of the human small intestinal epithelium, and is broadly applicable to model other tissues that rely on gradients for physiological function.
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404
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Khalid N, Kobayashi I, Nakajima M. Recent lab-on-chip developments for novel drug discovery. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2017; 9. [DOI: 10.1002/wsbm.1381] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 12/11/2016] [Accepted: 12/20/2016] [Indexed: 12/11/2022]
Affiliation(s)
- Nauman Khalid
- School of Food and Agricultural Sciences; University of Management and Technology; Lahore Pakistan
- Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences; Deakin University; Waurn Ponds Australia
- Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba Japan
| | - Isao Kobayashi
- Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba Japan
- Food Research Institute; NARO; Tsukuba Japan
| | - Mitsutoshi Nakajima
- Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba Japan
- Food Research Institute; NARO; Tsukuba Japan
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405
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Yu H, Hasan NM, In JG, Estes MK, Kovbasnjuk O, Zachos NC, Donowitz M. The Contributions of Human Mini-Intestines to the Study of Intestinal Physiology and Pathophysiology. Annu Rev Physiol 2017; 79:291-312. [PMID: 28192061 PMCID: PMC5549102 DOI: 10.1146/annurev-physiol-021115-105211] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The lack of accessibility to normal and diseased human intestine and the inability to separate the different functional compartments of the intestine even when tissue could be obtained have held back the understanding of human intestinal physiology. Clevers and his associates identified intestinal stem cells and established conditions to grow "mini-intestines" ex vivo in differentiated and undifferentiated conditions. This pioneering work has made a new model of the human intestine available and has begun making contributions to the understanding of human intestinal transport in normal physiologic conditions and the pathophysiology of intestinal diseases. However, this model is reductionist and lacks many of the complexities of normal intestine. Consequently, it is not yet possible to predict how great the advances using this model will be for understanding human physiology and pathophysiology, nor how the model will be modified to include multiple other intestinal cell types and physical forces necessary to more closely approximate normal intestine. This review describes recent studies using mini-intestines, which have readdressed previously established models of normal intestinal transport physiology and newly examined intestinal pathophysiology. The emphasis is on studies with human enteroids grown either as three-dimensional spheroids or two-dimensional monolayers. In addition, comments are provided on mouse studies in cases when human studies have not yet been described.
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Affiliation(s)
- Huimin Yu
- Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205;
| | - Nesrin M Hasan
- Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205;
| | - Julie G In
- Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205;
| | - Mary K Estes
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas 77030
| | - Olga Kovbasnjuk
- Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205;
| | - Nicholas C Zachos
- Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205;
| | - Mark Donowitz
- Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205;
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406
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Vaessen SFC, van Lipzig MMH, Pieters RHH, Krul CAM, Wortelboer HM, van de Steeg E. Regional Expression Levels of Drug Transporters and Metabolizing Enzymes along the Pig and Human Intestinal Tract and Comparison with Caco-2 Cells. Drug Metab Dispos 2017; 45:353-360. [PMID: 28153842 DOI: 10.1124/dmd.116.072231] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 01/09/2017] [Indexed: 01/06/2023] Open
Abstract
Intestinal transporter proteins and metabolizing enzymes play a crucial role in the oral absorption of a wide variety of drugs. The aim of the current study was to characterize better available intestinal in vitro models by comparing expression levels of these proteins and enzymes between porcine intestine, human intestine, and Caco-2 cells. We therefore determined the absolute protein expression of 19 drug transporters and the mRNA expression of 12 metabolic enzymes along the pig intestinal tract (duodenum, jejunum, ileum; N = 4), in human intestine (jejunum; N = 9), and Caco-2 cells. Expression of the included transporters and enzymes was in general well comparable between porcine and human intestinal tissue, although breast cancer resistance protein, monocarboxylate transporter 5, multidrug resistance protein (MRP) 1, MRP1, MRP3 (∼2-fold), and organic anion-transporting polypeptide (OATP) 4A1 (∼6-fold) was higher expressed in pig compared with human jejunum. Alternatively, expression level of relevant transporter proteins (glucose transporter 1, OATP4A1, MRP2, MRP1, and OATP2B1) was significantly higher (3- to 130-fold) in Caco-2 cells compared with human jejunum. Moreover, all examined CYPs showed at least a fivefold lower gene expression in Caco-2 cells compared with human jejunum, with the smallest differences for CYP1A1 and CYP3A5 and the largest difference for CYP3A4 (871-fold higher expression in human jejunum compared with Caco-2 cells). In conclusion, a comprehensive overview is provided of the expression levels of clinically relevant transporter proteins and metabolic enzymes in porcine and human intestinal tissue and Caco-2 cells, which may assist in deciding upon the most suitable model to further improve our understanding of processes that determine intestinal absorption of compounds.
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Affiliation(s)
- Stefan F C Vaessen
- TNO, Zeist, The Netherlands (M.M.H.L, C.A.M.K, H.M.W, E.S); Institute for Risk Assessment Sciences, Utrecht, The Netherlands (R.H.H.P, J.A.S,); Research Centre Technology & Innovation; and Innovative Testing in Life sciences and Chemistry, University of Applied Sciences, Utrecht, The Netherlands (S.F.C.V, R.H.H.P, C.A.M.K)
| | - Marola M H van Lipzig
- TNO, Zeist, The Netherlands (M.M.H.L, C.A.M.K, H.M.W, E.S); Institute for Risk Assessment Sciences, Utrecht, The Netherlands (R.H.H.P, J.A.S,); Research Centre Technology & Innovation; and Innovative Testing in Life sciences and Chemistry, University of Applied Sciences, Utrecht, The Netherlands (S.F.C.V, R.H.H.P, C.A.M.K)
| | - Raymond H H Pieters
- TNO, Zeist, The Netherlands (M.M.H.L, C.A.M.K, H.M.W, E.S); Institute for Risk Assessment Sciences, Utrecht, The Netherlands (R.H.H.P, J.A.S,); Research Centre Technology & Innovation; and Innovative Testing in Life sciences and Chemistry, University of Applied Sciences, Utrecht, The Netherlands (S.F.C.V, R.H.H.P, C.A.M.K)
| | - Cyrille A M Krul
- TNO, Zeist, The Netherlands (M.M.H.L, C.A.M.K, H.M.W, E.S); Institute for Risk Assessment Sciences, Utrecht, The Netherlands (R.H.H.P, J.A.S,); Research Centre Technology & Innovation; and Innovative Testing in Life sciences and Chemistry, University of Applied Sciences, Utrecht, The Netherlands (S.F.C.V, R.H.H.P, C.A.M.K)
| | - Heleen M Wortelboer
- TNO, Zeist, The Netherlands (M.M.H.L, C.A.M.K, H.M.W, E.S); Institute for Risk Assessment Sciences, Utrecht, The Netherlands (R.H.H.P, J.A.S,); Research Centre Technology & Innovation; and Innovative Testing in Life sciences and Chemistry, University of Applied Sciences, Utrecht, The Netherlands (S.F.C.V, R.H.H.P, C.A.M.K)
| | - Evita van de Steeg
- TNO, Zeist, The Netherlands (M.M.H.L, C.A.M.K, H.M.W, E.S); Institute for Risk Assessment Sciences, Utrecht, The Netherlands (R.H.H.P, J.A.S,); Research Centre Technology & Innovation; and Innovative Testing in Life sciences and Chemistry, University of Applied Sciences, Utrecht, The Netherlands (S.F.C.V, R.H.H.P, C.A.M.K)
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407
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408
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Organs-on-chips: research and commercial perspectives. Drug Discov Today 2017; 22:397-403. [DOI: 10.1016/j.drudis.2016.11.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 09/30/2016] [Accepted: 11/07/2016] [Indexed: 11/19/2022]
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409
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Villenave R, Wales SQ, Hamkins-Indik T, Papafragkou E, Weaver JC, Ferrante TC, Bahinski A, Elkins CA, Kulka M, Ingber DE. Human Gut-On-A-Chip Supports Polarized Infection of Coxsackie B1 Virus In Vitro. PLoS One 2017; 12:e0169412. [PMID: 28146569 PMCID: PMC5287454 DOI: 10.1371/journal.pone.0169412] [Citation(s) in RCA: 127] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 12/17/2016] [Indexed: 12/29/2022] Open
Abstract
Analysis of enterovirus infection is difficult in animals because they express different virus receptors than humans, and static cell culture systems do not reproduce the physical complexity of the human intestinal epithelium. Here, using coxsackievirus B1 (CVB1) as a prototype enterovirus strain, we demonstrate that human enterovirus infection, replication and infectious virus production can be analyzed in vitro in a human Gut-on-a-Chip microfluidic device that supports culture of highly differentiated human villus intestinal epithelium under conditions of fluid flow and peristalsis-like motions. When CVB1 was introduced into the epithelium-lined intestinal lumen of the device, virions entered the epithelium, replicated inside the cells producing detectable cytopathic effects (CPEs), and both infectious virions and inflammatory cytokines were released in a polarized manner from the cell apex, as they could be detected in the effluent from the epithelial microchannel. When the virus was introduced via a basal route of infection (by inoculating virus into fluid flowing through a parallel lower 'vascular' channel separated from the epithelial channel by a porous membrane), significantly lower viral titers, decreased CPEs, and delayed caspase-3 activation were observed; however, cytokines continued to be secreted apically. The presence of continuous fluid flow through the epithelial lumen also resulted in production of a gradient of CPEs consistent with the flow direction. Thus, the human Gut-on-a-Chip may provide a suitable in vitro model for enteric virus infection and for investigating mechanisms of enterovirus pathogenesis.
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Affiliation(s)
- Remi Villenave
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, Massachusetts, United States of America
| | - Samantha Q. Wales
- Molecular Virology Team, Division of Molecular Biology, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland, United States of America
| | - Tiama Hamkins-Indik
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, Massachusetts, United States of America
| | - Efstathia Papafragkou
- Molecular Virology Team, Division of Molecular Biology, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland, United States of America
| | - James C. Weaver
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, Massachusetts, United States of America
| | - Thomas C. Ferrante
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, Massachusetts, United States of America
| | - Anthony Bahinski
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, Massachusetts, United States of America
| | - Christopher A. Elkins
- Molecular Virology Team, Division of Molecular Biology, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland, United States of America
| | - Michael Kulka
- Molecular Virology Team, Division of Molecular Biology, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, Maryland, United States of America
| | - Donald E. Ingber
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, Massachusetts, United States of America
- Harvard John A. Paulson School of Engineering and Applied Sciences, Cambridge, Massachusetts, United States of America
- Vascular Biology Program, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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410
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Orbach SM, Less RR, Kothari A, Rajagopalan P. In Vitro Intestinal and Liver Models for Toxicity Testing. ACS Biomater Sci Eng 2017; 3:1898-1910. [PMID: 33440548 DOI: 10.1021/acsbiomaterials.6b00699] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The human body is exposed to hundreds of chemicals every day. Many of these toxicants have unknown effects on the body that can be deleterious. Furthermore, chemicals can have a synergistic effect, resulting in toxic responses of cocktails at relatively low individual exposure levels. The gastrointestinal (GI) tract and the liver are the first organs to be exposed to ingested pharmaceuticals and environmental chemicals. As a result, these organs often experience extensive damage from xenobiotics and their metabolites. In vitro models offer a promising method for testing toxic effects. Many advanced in vitro models have been developed for GI and liver toxicity. These models strive to recapitulate the in vivo organ architecture to more accurately model chemical toxicity. In this review, we discuss many of these advances, in addition to recent efforts to integrate the GI and the liver in vitro for a more holistic toxicity model.
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Affiliation(s)
- Sophia M Orbach
- Department of Chemical Engineering, ‡School of Biomedical Engineering and Sciences, and §ICTAS Center for Systems Biology of Engineered Tissue, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Rebekah R Less
- Department of Chemical Engineering, School of Biomedical Engineering and Sciences, and §ICTAS Center for Systems Biology of Engineered Tissue, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Anjaney Kothari
- Department of Chemical Engineering, School of Biomedical Engineering and Sciences, and ICTAS Center for Systems Biology of Engineered Tissue, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Padmavathy Rajagopalan
- Department of Chemical Engineering, School of Biomedical Engineering and Sciences, and ICTAS Center for Systems Biology of Engineered Tissue, Virginia Tech, Blacksburg, Virginia 24061, United States
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411
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Compartmentalized Culture of Perivascular Stroma and Endothelial Cells in a Microfluidic Model of the Human Endometrium. Ann Biomed Eng 2017; 45:1758-1769. [PMID: 28108942 PMCID: PMC5489603 DOI: 10.1007/s10439-017-1797-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 01/11/2017] [Indexed: 12/14/2022]
Abstract
The endometrium is the inner lining of the uterus. Following specific cyclic hormonal stimulation, endometrial stromal fibroblasts (stroma) and vascular endothelial cells exhibit morphological and biochemical changes to support embryo implantation and regulate vascular function, respectively. Herein, we integrated a resin-based porous membrane in a dual chamber microfluidic device in polydimethylsiloxane that allows long term in vitro co-culture of human endometrial stromal and endothelial cells. This transparent, 2-μm porous membrane separates the two chambers, allows for the diffusion of small molecules and enables high resolution bright field and fluorescent imaging. Within our primary human co-culture model of stromal and endothelial cells, we simulated the temporal hormone changes occurring during an idealized 28-day menstrual cycle. We observed the successful differentiation of stroma into functional decidual cells, determined by morphology as well as biochemically as measured by increased production of prolactin. By controlling the microfluidic properties of the device, we additionally found that shear stress forces promoted cytoskeleton alignment and tight junction formation in the endothelial layer. Finally, we demonstrated that the endometrial perivascular stroma model was sustainable for up to 4 weeks, remained sensitive to steroids and is suitable for quantitative biochemical analysis. Future utilization of this device will allow the direct evaluation of paracrine and endocrine crosstalk between these two cell types as well as studies of immunological events associated with normal vs. disease-related endometrial microenvironments.
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412
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Chang SY, Voellinger JL, Van Ness KP, Chapron B, Shaffer RM, Neumann T, White CC, Kavanagh TJ, Kelly EJ, Eaton DL. Characterization of rat or human hepatocytes cultured in microphysiological systems (MPS) to identify hepatotoxicity. Toxicol In Vitro 2017; 40:170-183. [PMID: 28089783 DOI: 10.1016/j.tiv.2017.01.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 01/05/2017] [Accepted: 01/11/2017] [Indexed: 12/12/2022]
Abstract
The liver is the main site for drug and xenobiotics metabolism, including inactivation or bioactivation. In order to improve the predictability of drug safety and efficacy in clinical development, and to facilitate the evaluation of the potential human health effects from exposure to environmental contaminants, there is a critical need to accurately model human organ systems such as the liver in vitro. We are developing a microphysiological system (MPS) based on a new commercial microfluidic platform (Nortis, Inc.) that can utilize primary liver cells from multiple species (e.g., rat and human). Compared to conventional monolayer cell culture, which typically survives for 5-7days or less, primary rat or human hepatocytes in an MPS exhibited higher viability and improved hepatic functions, such as albumin production, expression of hepatocyte marker HNF4α and canaliculi structure, for up to 14days. Additionally, induction of Cytochrome P450 (CYP) 1A and 3A4 in cryopreserved human hepatocytes was observed in the MPS. The acute cytotoxicity of the potent hepatotoxic and hepatocarcinogen, aflatoxin B1, was evaluated in human hepatocytes cultured in an MPS, demonstrating the utility of this model for acute hepatotoxicity assessment. These results indicate that MPS-cultured hepatocytes provide a promising approach for evaluating chemical toxicity in vitro.
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Affiliation(s)
- Shih-Yu Chang
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Jenna L Voellinger
- Department of Pharmaceutics, University of Washington, Seattle, WA 98195, USA
| | - Kirk P Van Ness
- Department of Pharmaceutics, University of Washington, Seattle, WA 98195, USA
| | - Brian Chapron
- Department of Pharmaceutics, University of Washington, Seattle, WA 98195, USA
| | - Rachel M Shaffer
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | | | - Collin C White
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Terrance J Kavanagh
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Edward J Kelly
- Department of Pharmaceutics, University of Washington, Seattle, WA 98195, USA
| | - David L Eaton
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA.
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413
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Borovjagin AV, Ogle BM, Berry JL, Zhang J. From Microscale Devices to 3D Printing: Advances in Fabrication of 3D Cardiovascular Tissues. Circ Res 2017; 120:150-165. [PMID: 28057791 PMCID: PMC5224928 DOI: 10.1161/circresaha.116.308538] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/03/2016] [Accepted: 10/19/2016] [Indexed: 01/14/2023]
Abstract
Current strategies for engineering cardiovascular cells and tissues have yielded a variety of sophisticated tools for studying disease mechanisms, for development of drug therapies, and for fabrication of tissue equivalents that may have application in future clinical use. These efforts are motivated by the need to extend traditional 2-dimensional (2D) cell culture systems into 3D to more accurately replicate in vivo cell and tissue function of cardiovascular structures. Developments in microscale devices and bioprinted 3D tissues are beginning to supplant traditional 2D cell cultures and preclinical animal studies that have historically been the standard for drug and tissue development. These new approaches lend themselves to patient-specific diagnostics, therapeutics, and tissue regeneration. The emergence of these technologies also carries technical challenges to be met before traditional cell culture and animal testing become obsolete. Successful development and validation of 3D human tissue constructs will provide powerful new paradigms for more cost effective and timely translation of cardiovascular tissue equivalents.
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Affiliation(s)
- Anton V Borovjagin
- From the Department of Biomedical Engineering, School of Medicine, School of Engineering, The University of Alabama at Birmingham (A.V.B., J.L.B., J.Z.); and Department of Biomedical Engineering, College of Science and Engineering, The University of Minnesota, Minneapolis (B.M.O.)
| | - Brenda M Ogle
- From the Department of Biomedical Engineering, School of Medicine, School of Engineering, The University of Alabama at Birmingham (A.V.B., J.L.B., J.Z.); and Department of Biomedical Engineering, College of Science and Engineering, The University of Minnesota, Minneapolis (B.M.O.)
| | - Joel L Berry
- From the Department of Biomedical Engineering, School of Medicine, School of Engineering, The University of Alabama at Birmingham (A.V.B., J.L.B., J.Z.); and Department of Biomedical Engineering, College of Science and Engineering, The University of Minnesota, Minneapolis (B.M.O.)
| | - Jianyi Zhang
- From the Department of Biomedical Engineering, School of Medicine, School of Engineering, The University of Alabama at Birmingham (A.V.B., J.L.B., J.Z.); and Department of Biomedical Engineering, College of Science and Engineering, The University of Minnesota, Minneapolis (B.M.O.).
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414
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415
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Three-Dimensional Tissue Models and Available Probes for Multi-Parametric Live Cell Microscopy: A Brief Overview. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1035:49-67. [DOI: 10.1007/978-3-319-67358-5_4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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416
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Horayama M, Shinha K, Kabayama K, Fujii T, Kimura H. Spatial Chemical Stimulation Control in Microenvironment by Microfluidic Probe Integrated Device for Cell-Based Assay. PLoS One 2016; 11:e0168158. [PMID: 27930750 PMCID: PMC5145238 DOI: 10.1371/journal.pone.0168158] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 11/24/2016] [Indexed: 12/15/2022] Open
Abstract
Cell—cell interactions play an important role in the development and function of multicellular organisms. To investigate these interactions in detail, it is necessary to evaluate the behavior of a cell population when the minimum number of cells in the population is stimulated by some chemical factors. We propose a microfluidic device integrated with microfluidic probe (MFP) functionality; this device is capable of imparting a chemical stimulus to cells within a microenvironment, for cell-based assays. The device contains MFP channels at the walls of the cell culture microchannels, and it can control a localized chemical stimulation area at the scale of a single cell to a few cells using MFP fluid control in a microspace. The results of a finite element method-based simulation indicated that it is possible to control the chemical stimulation area at the scale of a single cell to a few cells by optimizing the MFP channel apex width and the flow ratio. In addition, localized cell staining was demonstrated successfully using a spatial chemical stimulus. We confirmed the device functionality as a novel cell-based assay tool. We succeeded in performing localized cell collection using this method, which suggested that the single cell analysis of a cell monolayer that is subjected to a specific chemical stimulus is possible. The method proposed in this paper can contribute significantly to the fields of cell biology and drug development.
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Affiliation(s)
- Masayuki Horayama
- Department of Mechanical Engineering, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Kenta Shinha
- Department of Mechanical Engineering, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Kazuya Kabayama
- Department of Chemistry, Osaka University, Toyonaka, Osaka, Japan
- Micro/Nano Technology Center, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Teruo Fujii
- Institute of Industrial Science, The University of Tokyo, Meguro, Tokyo, Japan
| | - Hiroshi Kimura
- Department of Mechanical Engineering, Tokai University, Hiratsuka, Kanagawa, Japan
- Micro/Nano Technology Center, Tokai University, Hiratsuka, Kanagawa, Japan
- * E-mail:
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417
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Lundquist P, Artursson P. Oral absorption of peptides and nanoparticles across the human intestine: Opportunities, limitations and studies in human tissues. Adv Drug Deliv Rev 2016; 106:256-276. [PMID: 27496705 DOI: 10.1016/j.addr.2016.07.007] [Citation(s) in RCA: 312] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 07/02/2016] [Accepted: 07/08/2016] [Indexed: 12/23/2022]
Abstract
In this contribution, we review the molecular and physiological barriers to oral delivery of peptides and nanoparticles. We discuss the opportunities and predictivity of various in vitro systems with special emphasis on human intestine in Ussing chambers. First, the molecular constraints to peptide absorption are discussed. Then the physiological barriers to peptide delivery are examined. These include the gastric and intestinal environment, the mucus barrier, tight junctions between epithelial cells, the enterocytes of the intestinal epithelium, and the subepithelial tissue. Recent data from human proteome studies are used to provide information about the protein expression profiles of the different physiological barriers to peptide and nanoparticle absorption. Strategies that have been employed to increase peptide absorption across each of the barriers are discussed. Special consideration is given to attempts at utilizing endogenous transcytotic pathways. To reliably translate in vitro data on peptide or nanoparticle permeability to the in vivo situation in a human subject, the in vitro experimental system needs to realistically capture the central aspects of the mentioned barriers. Therefore, characteristics of common in vitro cell culture systems are discussed and compared to those of human intestinal tissues. Attempts to use the cell and tissue models for in vitro-in vivo extrapolation are reviewed.
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Affiliation(s)
- P Lundquist
- Department of Pharmacy, Uppsala University, Box 580, SE-752 37 Uppsala, Sweden.
| | - P Artursson
- Department of Pharmacy, Uppsala University, Box 580, SE-752 37 Uppsala, Sweden.
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418
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Dawson A, Dyer C, Macfie J, Davies J, Karsai L, Greenman J, Jacobsen M. A microfluidic chip based model for the study of full thickness human intestinal tissue using dual flow. BIOMICROFLUIDICS 2016; 10:064101. [PMID: 27822333 PMCID: PMC5097047 DOI: 10.1063/1.4964813] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 09/30/2016] [Indexed: 05/09/2023]
Abstract
The study of inflammatory bowel disease, including Ulcerative Colitis and Crohn's Disease, has relied largely upon the use of animal or cell culture models; neither of which can represent all aspects of the human pathophysiology. Presented herein is a dual flow microfluidic device which holds full thickness human intestinal tissue in a known orientation. The luminal and serosal sides are independently perfused ex vivo with nutrients with simultaneous waste removal for up to 72 h. The microfluidic device maintains the viability and integrity of the tissue as demonstrated through Haematoxylin & Eosin staining, immunohistochemistry and release of lactate dehydrogenase. In addition, the inflammatory state remains in the tissue after perfusion on the device as determined by measuring calprotectin levels. It is anticipated that this human model will be extremely useful for studying the biology and testing novel interventions in diseased tissue.
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Affiliation(s)
- A Dawson
- Faculty of Life Sciences, University of Hull , Cottingham Road, Hull HU6 7RX, United Kingdom
| | - C Dyer
- Faculty of Life Sciences, University of Hull , Cottingham Road, Hull HU6 7RX, United Kingdom
| | - J Macfie
- Scarborough Hospital , Woodlands Drive, Scarborough Y012 6QL, United Kingdom
| | - J Davies
- General Surgery, Castlehill Hospital , Castle Rd, Cottingham HU16 5JQ, United Kingdom
| | - L Karsai
- Pathology Building, Hull Royal Infirmary , Anlaby Road, Hull HU3 2JZ, United Kingdom
| | - J Greenman
- Faculty of Life Sciences, University of Hull , Cottingham Road, Hull HU6 7RX, United Kingdom
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419
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420
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Pereira JFS, Awatade NT, Loureiro CA, Matos P, Amaral MD, Jordan P. The third dimension: new developments in cell culture models for colorectal research. Cell Mol Life Sci 2016; 73:3971-89. [PMID: 27147463 PMCID: PMC11108567 DOI: 10.1007/s00018-016-2258-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 04/20/2016] [Accepted: 04/28/2016] [Indexed: 12/23/2022]
Abstract
Cellular models are important tools in various research areas related to colorectal biology and associated diseases. Herein, we review the most widely used cell lines and the different techniques to grow them, either as cell monolayer, polarized two-dimensional epithelia on membrane filters, or as three-dimensional spheres in scaffold-free or matrix-supported culture conditions. Moreover, recent developments, such as gut-on-chip devices or the ex vivo growth of biopsy-derived organoids, are also discussed. We provide an overview on the potential applications but also on the limitations for each of these techniques, while evaluating their contribution to provide more reliable cellular models for research, diagnostic testing, or pharmacological validation related to colon physiology and pathophysiology.
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Affiliation(s)
- Joana F S Pereira
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisbon, Portugal
- BioISI-Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Nikhil T Awatade
- BioISI-Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Cláudia A Loureiro
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisbon, Portugal
- BioISI-Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Paulo Matos
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisbon, Portugal
- BioISI-Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Margarida D Amaral
- BioISI-Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Peter Jordan
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016, Lisbon, Portugal.
- BioISI-Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon, Portugal.
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421
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422
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Choi JH, Lee J, Shin W, Choi JW, Kim HJ. Priming nanoparticle-guided diagnostics and therapeutics towards human organs-on-chips microphysiological system. NANO CONVERGENCE 2016; 3:24. [PMID: 28191434 PMCID: PMC5271165 DOI: 10.1186/s40580-016-0084-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 09/13/2016] [Indexed: 05/17/2023]
Abstract
Nanotechnology and bioengineering have converged over the past decades, by which the application of multi-functional nanoparticles (NPs) has been emerged in clinical and biomedical fields. The NPs primed to detect disease-specific biomarkers or to deliver biopharmaceutical compounds have beena validated in conventional in vitro culture models including two dimensional (2D) cell cultures or 3D organoid models. However, a lack of experimental models that have strong human physiological relevance has hampered accurate validation of the safety and functionality of NPs. Alternatively, biomimetic human "Organs-on-Chips" microphysiological systems have recapitulated the mechanically dynamic 3D tissue interface of human organ microenvironment, in which the transport, cytotoxicity, biocompatibility, and therapeutic efficacy of NPs and their conjugates may be more accurately validated. Finally, integration of NP-guided diagnostic detection and targeted nanotherapeutics in conjunction with human organs-on-chips can provide a novel avenue to accelerate the NP-based drug development process as well as the rapid detection of cellular secretomes associated with pathophysiological processes.
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Affiliation(s)
- Jin-Ha Choi
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712 USA
| | - Jaewon Lee
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712 USA
| | - Woojung Shin
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712 USA
| | - Jeong-Woo Choi
- Department of Chemical & Biomolecular Engineering, Sogang University, Seoul, 04107 Republic of Korea
- Interdisciplinary Program of Integrated Biotechnology, Sogang University, Seoul, 04107 Republic of Korea
| | - Hyun Jung Kim
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712 USA
- School of Medicine, Pusan National University, Yangsan, 50612 Republic of Korea
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423
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Effect of flow and peristaltic mixing on bacterial growth in a gut-like channel. Proc Natl Acad Sci U S A 2016; 113:11414-11419. [PMID: 27681630 DOI: 10.1073/pnas.1601306113] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The ecology of microbes in the gut has been shown to play important roles in the health of the host. To better understand microbial growth and population dynamics in the proximal colon, the primary region of bacterial growth in the gut, we built and applied a fluidic channel that we call the "minigut." This is a channel with an array of membrane valves along its length, which allows mimicking active contractions of the colonic wall. Repeated contraction is shown to be crucial in maintaining a steady-state bacterial population in the device despite strong flow along the channel that would otherwise cause bacterial washout. Depending on the flow rate and the frequency of contractions, the bacterial density profile exhibits varying spatial dependencies. For a synthetic cross-feeding community, the species abundance ratio is also strongly affected by mixing and flow along the length of the device. Complex mixing dynamics due to contractions is described well by an effective diffusion term. Bacterial dynamics is captured by a simple reaction-diffusion model without adjustable parameters. Our results suggest that flow and mixing play a major role in shaping the microbiota of the colon.
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424
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Pistollato F, Sumalla Cano S, Elio I, Masias Vergara M, Giampieri F, Battino M. Role of gut microbiota and nutrients in amyloid formation and pathogenesis of Alzheimer disease. Nutr Rev 2016; 74:624-34. [DOI: 10.1093/nutrit/nuw023] [Citation(s) in RCA: 282] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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425
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Picollet-D’hahan N, Dolega ME, Liguori L, Marquette C, Le Gac S, Gidrol X, Martin DK. A 3D Toolbox to Enhance Physiological Relevance of Human Tissue Models. Trends Biotechnol 2016; 34:757-769. [DOI: 10.1016/j.tibtech.2016.06.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/17/2016] [Accepted: 06/28/2016] [Indexed: 01/21/2023]
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426
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Pensabene V, Costa L, Terekhov A, Gnecco JS, Wikswo J, Hofmeister W. Ultrathin Polymer Membranes with Patterned, Micrometric Pores for Organs-on-Chips. ACS APPLIED MATERIALS & INTERFACES 2016; 8:22629-36. [PMID: 27513606 PMCID: PMC5131702 DOI: 10.1021/acsami.6b05754] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The basal lamina or basement membrane (BM) is a key physiological system that participates in physicochemical signaling between tissue types. Its formation and function are essential in tissue maintenance, growth, angiogenesis, disease progression, and immunology. In vitro models of the BM (e.g., Boyden and transwell chambers) are common in cell biology and lab-on-a-chip devices where cells require apical and basolateral polarization. Extravasation, intravasation, membrane transport of chemokines, cytokines, chemotaxis of cells, and other key functions are routinely studied in these models. The goal of the present study was to integrate a semipermeable ultrathin polymer membrane with precisely positioned pores of 2 μm diameter in a microfluidic device with apical and basolateral chambers. We selected poly(l-lactic acid) (PLLA), a transparent biocompatible polymer, to prepare the semipermeable ultrathin membranes. The pores were generated by pattern transfer using a three-step method coupling femtosecond laser machining, polymer replication, and spin coating. Each step of the fabrication process was characterized by scanning electron microscopy to investigate reliability of the process and fidelity of pattern transfer. In order to evaluate the compatibility of the fabrication method with organs-on-a-chip technology, porous PLLA membranes were embedded in polydimethylsiloxane (PDMS) microfluidic devices and used to grow human umbilical vein endothelial cells (HUVECS) on top of the membrane with perfusion through the basolateral chamber. Viability of cells, optical transparency of membranes and strong adhesion of PLLA to PDMS were observed, thus confirming the suitability of the prepared membranes for use in organs-on-a-chip devices.
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Affiliation(s)
- Virginia Pensabene
- Department of Biomedical Engineering; Vanderbilt University, Nashville, TN 37235 USA
- School of Electronic and Electrical Engineering, University of Leeds, Leeds, LS2 9JT, UK
- School of Medicine, Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, LS9 7TF, UK
| | - Lino Costa
- Center for Laser Applications, University of Tennessee Space Institute, Tullahoma, TN 37388 USA
| | - Alexander Terekhov
- Center for Laser Applications, University of Tennessee Space Institute, Tullahoma, TN 37388 USA
| | - Juan S. Gnecco
- Department of Cellular and Molecular Pathology, Vanderbilt University, Nashville, TN 37235 USA
| | - John Wikswo
- Department of Biomedical Engineering; Vanderbilt University, Nashville, TN 37235 USA
- Vanderbilt Institute for Integrative Biosystems Research and Education; Vanderbilt University, Nashville, TN 37235 USA
- Department of Physics and Astronomy; Vanderbilt University, Nashville, TN 37235 USA
- Department of Molecular Physiology and Biophysics; Vanderbilt University, Nashville, TN 37235 USA
| | - William Hofmeister
- Center for Laser Applications, University of Tennessee Space Institute, Tullahoma, TN 37388 USA
- Vanderbilt Institute for Integrative Biosystems Research and Education; Vanderbilt University, Nashville, TN 37235 USA
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427
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Kim HJ, Lee J, Choi JH, Bahinski A, Ingber DE. Co-culture of Living Microbiome with Microengineered Human Intestinal Villi in a Gut-on-a-Chip Microfluidic Device. J Vis Exp 2016. [PMID: 27684630 DOI: 10.3791/54344] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Here, we describe a protocol to perform long-term co-culture of multi-species human gut microbiome with microengineered intestinal villi in a human gut-on-a-chip microphysiological device. We recapitulate the intestinal lumen-capillary tissue interface in a microfluidic device, where physiological mechanical deformations and fluid shear flow are constantly applied to mimic peristalsis. In the lumen microchannel, human intestinal epithelial Caco-2 cells are cultured to form a 'germ-free' villus epithelium and regenerate small intestinal villi. Pre-cultured microbial cells are inoculated into the lumen side to establish a host-microbe ecosystem. After microbial cells adhere to the apical surface of the villi, fluid flow and mechanical deformations are resumed to produce a steady-state microenvironment in which fresh culture medium is constantly supplied and unbound bacteria (as well as bacterial wastes) are continuously removed. After extended co-culture from days to weeks, multiple microcolonies are found to be randomly located between the villi, and both microbial and epithelial cells remain viable and functional for at least one week in culture. Our co-culture protocol can be adapted to provide a versatile platform for other host-microbiome ecosystems that can be found in various human organs, which may facilitate in vitro study of the role of human microbiome in orchestrating health and disease.
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Affiliation(s)
- Hyun Jung Kim
- Department of Biomedical Engineering, The University of Texas at Austin;
| | - Jaewon Lee
- Department of Biomedical Engineering, The University of Texas at Austin
| | - Jin-Ha Choi
- Department of Biomedical Engineering, The University of Texas at Austin
| | - Anthony Bahinski
- Wyss Institute for Biologically Inspired Engineering at Harvard University
| | - Donald E Ingber
- Wyss Institute for Biologically Inspired Engineering at Harvard University; Vascular Biology Program, Boston Children's Hospital, Harvard Medical School; John A. Paulson School of Engineering and Applied Sciences, Harvard University
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428
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The motility of Entamoeba histolytica: finding ways to understand intestinal amoebiasis. Curr Opin Microbiol 2016; 34:24-30. [PMID: 27497052 DOI: 10.1016/j.mib.2016.07.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/21/2016] [Accepted: 07/25/2016] [Indexed: 12/16/2022]
Abstract
The pathogenic amoeba Entamoeba histolytica is able to migrate within various compartments of the human body. The present article reviews progress in understanding the mechanisms of cell motility in E. histolytica during human intestinal invasion and, in particular, how the three-dimensional characteristics of the environment regulate the parasite's behaviour. The amoeboid mode of migration that applies to E. histolytica's displacements on two-dimensional surfaces is also expected to apply to the three-dimensional environment in the human intestine although several unknown, distinct modalities may be involved. Recent advances in the field of tissue engineering have provided clues on how the construction of a human colon model could help us to understand the host's intestinal physiology and its changes following amoebic infection.
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429
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Shatkin JA, Ong KJ. Alternative Testing Strategies for Nanomaterials: State of the Science and Considerations for Risk Analysis. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2016; 36:1564-1580. [PMID: 27273523 DOI: 10.1111/risa.12642] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 03/02/2016] [Accepted: 04/19/2016] [Indexed: 06/06/2023]
Abstract
The rapid growth of the nanotechnology industry has warranted equal progress in the nanotoxicology and risk assessment fields. In vivo models have traditionally been used to determine human and environmental risk for chemicals; however, the use of these tests has limitations, and there are global appeals to develop reliable alternatives to animal testing. Many have investigated the use of alternative (nonanimal) testing methods and strategies have quickly developed and resulted in the generation of large toxicological data sets for numerous nanomaterials (NMs). Due to the novel physicochemical properties of NMs that are related to surface characteristics, the approach toward toxicity test development has distinct considerations from traditional chemicals, bringing new requirements for adapting these approaches for NMs. The methodical development of strategies that combine multiple alternative tests can be useful for predictive NM risk assessment and help screening-level decision making. This article provides an overview of the main developments in alternative methods and strategies for reducing uncertainty in NM risk assessment, including advantages and disadvantages of in vitro, ex vivo, and in silico methods, and examples of existing comprehensive strategies. In addition, knowledge gaps are identified toward improvements for experimental and strategy design, specifically highlighting the need to represent realistic exposure scenarios and to consider NM-specific concerns such as characterization, assay interferences, and standardization. Overall, this article aims to improve the reliability and utility of alternative testing methods and strategies for risk assessment of manufactured NMs.
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Affiliation(s)
| | - K J Ong
- Vireo Advisors, LLC, Boston, MA, USA
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430
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Lee J, Choi JH, Kim HJ. Human gut-on-a-chip technology: will this revolutionize our understanding of IBD and future treatments? Expert Rev Gastroenterol Hepatol 2016; 10:883-5. [PMID: 27291426 DOI: 10.1080/17474124.2016.1200466] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jaewon Lee
- a Department of Biomedical Engineering , The University of Texas at Austin , Austin , TX , USA
| | - Jin-Ha Choi
- a Department of Biomedical Engineering , The University of Texas at Austin , Austin , TX , USA
| | - Hyun Jung Kim
- a Department of Biomedical Engineering , The University of Texas at Austin , Austin , TX , USA
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431
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Emerging Technologies for Gut Microbiome Research. Trends Microbiol 2016; 24:887-901. [PMID: 27426971 DOI: 10.1016/j.tim.2016.06.008] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 06/06/2016] [Accepted: 06/23/2016] [Indexed: 02/06/2023]
Abstract
Understanding the importance of the gut microbiome on modulation of host health has become a subject of great interest for researchers across disciplines. As an intrinsically multidisciplinary field, microbiome research has been able to reap the benefits of technological advancements in systems and synthetic biology, biomaterials engineering, and traditional microbiology. Gut microbiome research has been revolutionized by high-throughput sequencing technology, permitting compositional and functional analyses that were previously an unrealistic undertaking. Emerging technologies, including engineered organoids derived from human stem cells, high-throughput culturing, and microfluidics assays allowing for the introduction of novel approaches, will improve the efficiency and quality of microbiome research. Here, we discuss emerging technologies and their potential impact on gut microbiome studies.
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432
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Organ-on-chip models: new opportunities for biomedical research. Future Sci OA 2016; 3:FSO130. [PMID: 28670461 PMCID: PMC5481808 DOI: 10.4155/fsoa-2016-0038] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 05/31/2016] [Indexed: 01/10/2023] Open
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433
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Kang TH, Kim HJ. Farewell to Animal Testing: Innovations on Human Intestinal Microphysiological Systems. MICROMACHINES 2016; 7:mi7070107. [PMID: 30404281 PMCID: PMC6190004 DOI: 10.3390/mi7070107] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 06/21/2016] [Accepted: 06/21/2016] [Indexed: 02/06/2023]
Abstract
The human intestine is a dynamic organ where the complex host-microbe interactions that orchestrate intestinal homeostasis occur. Major contributing factors associated with intestinal health and diseases include metabolically-active gut microbiota, intestinal epithelium, immune components, and rhythmical bowel movement known as peristalsis. Human intestinal disease models have been developed; however, a considerable number of existing models often fail to reproducibly predict human intestinal pathophysiology in response to biological and chemical perturbations or clinical interventions. Intestinal organoid models have provided promising cytodifferentiation and regeneration, but the lack of luminal flow and physical bowel movements seriously hamper mimicking complex host-microbe crosstalk. Here, we discuss recent advances of human intestinal microphysiological systems, such as the biomimetic human "Gut-on-a-Chip" that can employ key intestinal components, such as villus epithelium, gut microbiota, and immune components under peristalsis-like motions and flow, to reconstitute the transmural 3D lumen-capillary tissue interface. By encompassing cutting-edge tools in microfluidics, tissue engineering, and clinical microbiology, gut-on-a-chip has been leveraged not only to recapitulate organ-level intestinal functions, but also emulate the pathophysiology of intestinal disorders, such as chronic inflammation. Finally, we provide potential perspectives of the next generation microphysiological systems as a personalized platform to validate the efficacy, safety, metabolism, and therapeutic responses of new drug compounds in the preclinical stage.
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Affiliation(s)
- Tae Hyun Kang
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
| | - Hyun Jung Kim
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
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434
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Fröhlich E, Roblegg E. Oral uptake of nanoparticles: human relevance and the role of in vitro systems. Arch Toxicol 2016; 90:2297-314. [PMID: 27342244 DOI: 10.1007/s00204-016-1765-0] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 06/14/2016] [Indexed: 01/03/2023]
Abstract
Nanoparticles (NPs) present in environment, consumer and health products, food and medical applications lead to a high degree of human exposure and concerns about potential adverse effects on human health. For the general population, the exposure through contact with the skin, inhalation and oral uptake are most relevant. Since in vivo testing is only partly able to study the effects of human oral exposure, physiologically relevant in vitro systems are being developed. This review compared the three routes taking into account the estimated concentration, size of the exposed area, morphology of the involved barrier and translocation rate. The high amounts of NPs in food, the large absorption area and the relatively high translocation rate identified oral uptake as most important portal of entry for NPs into the body. Changes of NP properties in the physiological fluids, mechanisms to cross mucus and epithelial barrier, and important issues in the use of laboratory animals for oral exposure are mentioned. The ability of in vitro models to address the varying conditions along the oro-gastrointestinal tract is discussed, and requirements for physiologically relevant in vitro testing of orally ingested NPs are listed.
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Affiliation(s)
- Eleonore Fröhlich
- Center for Medical Research, Medical University of Graz, Stiftingtalstr. 24, 8010, Graz, Austria.
| | - Eva Roblegg
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Technology, Karl-Franzens-University of Graz, Graz, Austria
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435
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Date AA, Hanes J, Ensign LM. Nanoparticles for oral delivery: Design, evaluation and state-of-the-art. J Control Release 2016; 240:504-526. [PMID: 27292178 DOI: 10.1016/j.jconrel.2016.06.016] [Citation(s) in RCA: 258] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 06/07/2016] [Accepted: 06/08/2016] [Indexed: 02/06/2023]
Abstract
The oral route is a preferred method of drug administration, though achieving effective drug delivery and minimizing off-target side effects is often challenging. Formulation into nanoparticles can improve drug stability in the harsh gastrointestinal (GI) tract environment, providing opportunities for targeting specific sites in the GI tract, increasing drug solubility and bioavailability, and providing sustained release in the GI tract. However, the unique and diverse physiology throughout the GI tract, including wide variation in pH, mucus that varies in thickness and structure, numerous cell types, and various physiological functions are both a barrier to effective delivery and an opportunity for nanoparticle design. Here, nanoparticle design aspects to improve delivery to particular sites in the GI tract are discussed. We then review new methods for evaluating oral nanoparticle formulations, including a short commentary on data interpretation and translation. Finally, the state-of-the-art in preclinical targeted nanoparticle design is reviewed.
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Affiliation(s)
- Abhijit A Date
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N Broadway, Baltimore, MD 21231, USA; Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD 21231, USA
| | - Justin Hanes
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N Broadway, Baltimore, MD 21231, USA; Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD 21231, USA; Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA; Departments of Biomedical Engineering, Environmental and Health Sciences, Oncology, Neurosurgery, Pharmacology and Molecular Sciences, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Laura M Ensign
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N Broadway, Baltimore, MD 21231, USA; Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, 400 N. Broadway, Baltimore, MD 21231, USA; Department of Chemical and Biomolecular Engineering, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA.
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436
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Mortensen NP, Mercier KA, McRitchie S, Cavallo TB, Pathmasiri W, Stewart D, Sumner SJ. Microfluidics meets metabolomics to reveal the impact of Campylobacter jejuni infection on biochemical pathways. Biomed Microdevices 2016; 18:51. [PMID: 27231016 PMCID: PMC4939818 DOI: 10.1007/s10544-016-0076-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Microfluidic devices that are currently being used in pharmaceutical research also have a significant potential for utilization in investigating exposure to infectious agents. We have established a microfluidic device cultured with Caco-2 cells, and utilized metabolomics to investigate the biochemical responses to the bacterial pathogen Campylobacter jejuni. In the microfluidic devices, Caco-2 cells polarize at day 5, are uniform, have defined brush borders and tight junctions, and form a mucus layer. Metabolomics analysis of cell culture media collected from both Caco-2 cell culture systems demonstrated a more metabolic homogenous biochemical profile in the media collected from microfluidic devices, compared with media collected from transwells. GeneGo pathway mapping indicated that aminoacyl-tRNA biosynthesis was perturbed by fluid flow, suggesting that fluid dynamics and shear stress impacts the cells translational quality control. Both microfluidic device and transwell culturing systems were used to investigate the impact of Campylobacter jejuni infection on biochemical processes. Caco-2 cells cultured in either system were infected at day 5 with C. jejuni 81-176 for 48 h. Metabolomics analysis clearly differentiated C. jejuni 81-176 infected and non-infected medias collected from the microfluidic devices, and demonstrated that C. jejuni 81-176 infection in microfluidic devices impacts branched-chain amino acid metabolism, glycolysis, and gluconeogenesis. In contrast, no distinction was seen in the biochemical profiles of infected versus non-infected media collected from cells cultured in transwells. Microfluidic culturing conditions demonstrated a more metabolically homogenous cell population, and present the opportunity for studying host-pathogen interactions for extended periods of time.
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Affiliation(s)
- Ninell P Mortensen
- Systems and Translational Sciences Discovery - Science - Technology, RTI International, 3040 Cornwallis Drive, Research Triangle Park, NC, 27709, USA.
| | - Kelly A Mercier
- Systems and Translational Sciences Discovery - Science - Technology, RTI International, 3040 Cornwallis Drive, Research Triangle Park, NC, 27709, USA
- NIH Eastern Regional Comprehensive Metabolomics Resource Core, Systems and Translational Sciences, RTI International, 3040 East Cornwallis Road, Research Triangle Park, NC, 27709-2194, USA
| | - Susan McRitchie
- Systems and Translational Sciences Discovery - Science - Technology, RTI International, 3040 Cornwallis Drive, Research Triangle Park, NC, 27709, USA
- NIH Eastern Regional Comprehensive Metabolomics Resource Core, Systems and Translational Sciences, RTI International, 3040 East Cornwallis Road, Research Triangle Park, NC, 27709-2194, USA
| | - Tammy B Cavallo
- Systems and Translational Sciences Discovery - Science - Technology, RTI International, 3040 Cornwallis Drive, Research Triangle Park, NC, 27709, USA
- NIH Eastern Regional Comprehensive Metabolomics Resource Core, Systems and Translational Sciences, RTI International, 3040 East Cornwallis Road, Research Triangle Park, NC, 27709-2194, USA
| | - Wimal Pathmasiri
- Systems and Translational Sciences Discovery - Science - Technology, RTI International, 3040 Cornwallis Drive, Research Triangle Park, NC, 27709, USA
- NIH Eastern Regional Comprehensive Metabolomics Resource Core, Systems and Translational Sciences, RTI International, 3040 East Cornwallis Road, Research Triangle Park, NC, 27709-2194, USA
| | - Delisha Stewart
- Systems and Translational Sciences Discovery - Science - Technology, RTI International, 3040 Cornwallis Drive, Research Triangle Park, NC, 27709, USA
- NIH Eastern Regional Comprehensive Metabolomics Resource Core, Systems and Translational Sciences, RTI International, 3040 East Cornwallis Road, Research Triangle Park, NC, 27709-2194, USA
| | - Susan J Sumner
- Systems and Translational Sciences Discovery - Science - Technology, RTI International, 3040 Cornwallis Drive, Research Triangle Park, NC, 27709, USA.
- NIH Eastern Regional Comprehensive Metabolomics Resource Core, Systems and Translational Sciences, RTI International, 3040 East Cornwallis Road, Research Triangle Park, NC, 27709-2194, USA.
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437
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Verma R, Adhikary RR, Banerjee R. Smart material platforms for miniaturized devices: implications in disease models and diagnostics. LAB ON A CHIP 2016; 16:1978-1992. [PMID: 27108534 DOI: 10.1039/c6lc00173d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Smart materials are responsive to multiple stimuli like light, temperature, pH and redox reactions with specific changes in state. Various functionalities in miniaturised devices can be achieved through the application of "smart materials" that respond to changes in their surroundings. The change in state of the materials in the presence of a stimulus may be used for on demand alteration of flow patterns in devices, acting as microvalves, as scaffolds for cellular aggregation or as modalities for signal amplification. In this review, we discuss the concepts of smart trigger responsive materials and their applications in miniaturized devices both for organ-on-a-chip disease models and for point-of-care diagnostics. The emphasis is on leveraging the smartness of these materials for example, to allow on demand sample actuation, ion dependent spheroid models for cancer or light dependent contractility of muscle films for organ-on-a-chip applications. The review throws light on the current status, scope for technological enhancements, challenges for translation and future prospects of increased incorporation of smart materials as integral parts of miniaturized devices.
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Affiliation(s)
- Ritika Verma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, India.
| | - Rishi Rajat Adhikary
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, India.
| | - Rinti Banerjee
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, India.
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438
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Marx U, Andersson TB, Bahinski A, Beilmann M, Beken S, Cassee FR, Cirit M, Daneshian M, Fitzpatrick S, Frey O, Gaertner C, Giese C, Griffith L, Hartung T, Heringa MB, Hoeng J, de Jong WH, Kojima H, Kuehnl J, Luch A, Maschmeyer I, Sakharov D, Sips AJAM, Steger-Hartmann T, Tagle DA, Tonevitsky A, Tralau T, Tsyb S, van de Stolpe A, Vandebriel R, Vulto P, Wang J, Wiest J, Rodenburg M, Roth A. Biology-inspired microphysiological system approaches to solve the prediction dilemma of substance testing. ALTEX 2016; 33:272-321. [PMID: 27180100 PMCID: PMC5396467 DOI: 10.14573/altex.1603161] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/11/2016] [Indexed: 01/09/2023]
Abstract
The recent advent of microphysiological systems - microfluidic biomimetic devices that aspire to emulate the biology of human tissues, organs and circulation in vitro - is envisaged to enable a global paradigm shift in drug development. An extraordinary US governmental initiative and various dedicated research programs in Europe and Asia have led recently to the first cutting-edge achievements of human single-organ and multi-organ engineering based on microphysiological systems. The expectation is that test systems established on this basis would model various disease stages, and predict toxicity, immunogenicity, ADME profiles and treatment efficacy prior to clinical testing. Consequently, this technology could significantly affect the way drug substances are developed in the future. Furthermore, microphysiological system-based assays may revolutionize our current global programs of prioritization of hazard characterization for any new substances to be used, for example, in agriculture, food, ecosystems or cosmetics, thus, replacing laboratory animal models used currently. Thirty-six experts from academia, industry and regulatory bodies present here the results of an intensive workshop (held in June 2015, Berlin, Germany). They review the status quo of microphysiological systems available today against industry needs, and assess the broad variety of approaches with fit-for-purpose potential in the drug development cycle. Feasible technical solutions to reach the next levels of human biology in vitro are proposed. Furthermore, key organ-on-a-chip case studies, as well as various national and international programs are highlighted. Finally, a roadmap into the future is outlined, to allow for more predictive and regulatory-accepted substance testing on a global scale.
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439
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Lu Q, Al-Sheikh O, Elisseeff JH, Grant MP. Biomaterials and Tissue Engineering Strategies for Conjunctival Reconstruction and Dry Eye Treatment. Middle East Afr J Ophthalmol 2016; 22:428-34. [PMID: 26692712 PMCID: PMC4660527 DOI: 10.4103/0974-9233.167818] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The ocular surface is a component of the anterior segment of the eye and is covered by the tear film. Together, they protect the vital external components of the eye from the environment. Injuries, surgical trauma, and autoimmune diseases can damage this system, and in severe cases, tissue engineering strategies are necessary to ensure proper wound healing and recovery. Dry eye is another major concern and a complicated disease affecting the ocular surface. More effective and innovative therapies are required for better outcomes in treating dry eye. This review focuses on the regenerative medicine of the conjunctiva, which is an essential part of the ocular surface system. Features and advances of different types of biomolecular materials, and autologous and allogeneic tissue grafts are summarized and compared. Specifically, vitrigel, a collagen membrane and novel material for use on the ocular surface, offers significant advantages over other biomaterials. This review also discusses a breakthrough microfluidic technology, “organ-on-a-chip” and its potential application in investigating new therapies for dry eye.
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Affiliation(s)
- Qiaozhi Lu
- Translational Tissue Engineering Center, Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21231, USA ; Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Osama Al-Sheikh
- Oculoplastics and Orbit Division, King Khaled Eye Specialist Hospital, P.O. Box 7191, Riyadh 11462, Saudi Arabia
| | - Jennifer H Elisseeff
- Translational Tissue Engineering Center, Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21231, USA ; Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Michael P Grant
- Oculoplastics Division, Ocular and Orbital Trauma Center, Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA
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440
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Xiong F, Megason SG. Abstracting the principles of development using imaging and modeling. Integr Biol (Camb) 2016; 7:633-42. [PMID: 25946995 DOI: 10.1039/c5ib00025d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Here we look at modern developmental biology with a focus on the relationship between different approaches of investigation. We argue that direct imaging is a powerful approach not only for obtaining descriptive information but also for model generation and testing that lead to mechanistic insights. Modeling, on the other hand, conceptualizes imaging data and provides guidance to perturbations. The inquiry progresses most efficiently when a trinity of approaches—quantitative imaging (measurement), modeling (theory) and perturbation (test)—are pursued in concert, but not when one approach is dominant. Using recent studies of the zebrafish system, we show how this combination has effectively advanced classic topics in developmental biology compared to a perturbation-centric approach. Finally, we show that interdisciplinary expertise and perhaps specialization are necessary for carrying out a systematic approach, and discuss the technical hurdles.
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Affiliation(s)
- Fengzhu Xiong
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA.
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441
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Kujala VJ, Pasqualini FS, Goss JA, Nawroth JC, Parker KK. Laminar ventricular myocardium on a microelectrode array-based chip. J Mater Chem B 2016; 4:3534-3543. [PMID: 32263387 DOI: 10.1039/c6tb00324a] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Pharmaceutical screening based on human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and multi electrode arrays (MEAs) have been proposed as a complementary method for electrophysiological safety and efficacy assessment in drug discovery and development. Contrary to animal models, these cells offer a human genetic background but, at present, fail to recapitulate the mechanical and structural properties of the native human myocardium. Here, we report that topographical cues on soft micromolded gelatin can coax hiPSC-CMs to form laminar cardiac tissues that resemble the native architecture of the heart. Importantly, using this method we were able to record tissue-level electrophysiological responses with a commercially available MEA setup. To validate this platform, we recorded cardiac field potentials at baseline and after pharmacological interventions with a β-adrenergic agonist (isoproterenol). Further, we tested the ability of our system to predict the response of laminar human cardiac tissues to a cardiotoxic pro-drug (terfenadine) and its non-cardiotoxic metabolite (fexofenadine). Finally, we integrated our platform with microfluidic components to build a heart-on-a-chip system that can be fluidically linked with other organs-on-chips in the future.
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Affiliation(s)
- Ville J Kujala
- Disease Biophysics Group, Harvard Stem Cell Institute, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, K.K.P. 29 Oxford Street, Pierce Hall Cambridge, MA 02130, USA.
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442
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Attayek PJ, Ahmad AA, Wang Y, Williamson I, Sims CE, Magness ST, Allbritton NL. In Vitro Polarization of Colonoids to Create an Intestinal Stem Cell Compartment. PLoS One 2016; 11:e0153795. [PMID: 27100890 PMCID: PMC4839657 DOI: 10.1371/journal.pone.0153795] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 04/04/2016] [Indexed: 12/22/2022] Open
Abstract
The polarity of proliferative and differentiated cellular compartments of colonic crypts is believed to be specified by gradients of key mitogens and morphogens. Indirect evidence demonstrates a tight correlation between Wnt- pathway activity and the basal-luminal patterning; however, to date there has been no direct experimental manipulation demonstrating that a chemical gradient of signaling factors can produce similar patterning under controlled conditions. In the current work, colonic organoids (colonoids) derived from cultured, multicellular organoid fragments or single stem cells were exposed in culture to steep linear gradients of two Wnt-signaling ligands, Wnt-3a and R-spondin1. The use of a genetically engineered Sox9-Sox9EGFP:CAGDsRED reporter gene mouse model and EdU-based labeling enabled crypt patterning to be quantified in the developing colonoids. Colonoids derived from multicellular fragments cultured for 5 days under a Wnt-3a or a combined Wnt-3a and R-spondin1 gradient were highly polarized with proliferative cells localizing to the region of the higher morphogen concentration. In a Wnt-3a gradient, Sox9EGFP polarization was 7.3 times greater than that of colonoids cultured in the absence of a gradient; and the extent of EdU polarization was 2.2 times greater than that in the absence of a gradient. Under a Wnt-3a/R-spondin1 gradient, Sox9EGFP polarization was 8.2 times greater than that of colonoids cultured in the absence of a gradient while the extent of EdU polarization was 10 times greater than that in the absence of a gradient. Colonoids derived from single stem cells cultured in Wnt-3a/R-spondin1 gradients were most highly polarized demonstrated by a Sox9EGFP polarization 20 times that of colonoids grown in the absence of a gradient. This data provides direct evidence that a linear gradient of Wnt signaling factors applied to colonic stem cells is sufficient to direct patterning of the colonoid unit in culture.
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Affiliation(s)
- Peter J. Attayek
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Asad A. Ahmad
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Yuli Wang
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, 27599, United States of America
| | - Ian Williamson
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Christopher E. Sims
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, 27599, United States of America
| | - Scott T. Magness
- Department of Medicine, Division of Gastroenterology and Hepatology, University of North Carolina, Chapel Hill, NC, 27599, United States of America
| | - Nancy L. Allbritton
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC, 27695, United States of America
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, 27599, United States of America
- * E-mail:
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443
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McCartney F, Gleeson JP, Brayden DJ. Safety concerns over the use of intestinal permeation enhancers: A mini-review. Tissue Barriers 2016; 4:e1176822. [PMID: 27358756 DOI: 10.1080/21688370.2016.1176822] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 03/18/2016] [Accepted: 03/22/2016] [Indexed: 12/22/2022] Open
Abstract
Intestinal permeation enhancers (PEs) are key components in ∼12 oral peptide formulations in clinical trials for a range of molecules, primarily insulin and glucagon-like-peptide 1 (GLP-1) analogs. The main PEs comprise medium chain fatty acid-based systems (sodium caprate, sodium caprylate, and N-[8-(2-hydroxybenzoyl) amino] caprylate (SNAC)), bile salts, acyl carnitines, and EDTA. Their mechanism of action is complex with subtle differences between the different molecules. With the exception of SNAC and EDTA, most PEs fluidize the plasma membrane causing plasma membrane perturbation, as well as enzymatic and intracellular mediator changes that lead to alteration of intestinal epithelial tight junction protein expression. The question arises as to whether PEs can cause irreversible epithelial damage and tight junction openings sufficient to permit co-absorption of payloads with bystander pathogens, lipopolysaccharides and its fragment, or exo- and endotoxins that may be associated with sepsis, inflammation and autoimmune conditions. Most PEs seem to cause membrane perturbation to varying extents that is rapidly reversible, and overall evidence of pathogen co-absorption is generally lacking. It is unknown however, whether the intestinal epithelial damage-repair cycle is sustained during repeat-dosing regimens for chronic therapy.
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Affiliation(s)
- Fiona McCartney
- UCD School of Veterinary Medicine and UCD Conway Institute, University College Dublin , Belfield, Dublin 4, Ireland
| | - John P Gleeson
- UCD School of Veterinary Medicine and UCD Conway Institute, University College Dublin , Belfield, Dublin 4, Ireland
| | - David J Brayden
- UCD School of Veterinary Medicine and UCD Conway Institute, University College Dublin , Belfield, Dublin 4, Ireland
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444
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Sugimura R. Bioengineering Hematopoietic Stem Cell Niche toward Regenerative Medicine. Adv Drug Deliv Rev 2016; 99:212-220. [PMID: 26527127 DOI: 10.1016/j.addr.2015.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 09/20/2015] [Accepted: 10/15/2015] [Indexed: 12/20/2022]
Abstract
The scope of this chapter is to introduce the current consensus of hematopoietic stem cell (HSC) niche biology to bioengineering field so that can apply to regenerative medicine. A decade of research has been addressing "what is HSC niche", then next step is "how it advances medicine". The demand to improve HSC transplantation has advanced the methodology to expand HSC in vitro. Still precise modeling of bone marrow (BM) is demanded by bioengineering HSC niche in vitro. Better understanding of HSC niche is essential toward this progress. Now it would be the time to apply the knowledge of HSC niche field to the venue of bioengineering, so that a promising new approach to regenerative medicine might appear. This chapter describes the current consensus of niche that endothelial cell and perivascular mesenchymal stromal cell maintain HSC, expansion of cord blood HSC by small molecules, bioengineering efforts to model HSC niche by microfluidics chip, organoids, and breakthroughs to induce HSC from heterologous types of cells.
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445
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Shirafkan A, Montalbano M, McGuire J, Rastellini C, Cicalese L. New approaches to increase intestinal length: Methods used for intestinal regeneration and bioengineering. World J Transplant 2016; 6:1-9. [PMID: 27011901 PMCID: PMC4801784 DOI: 10.5500/wjt.v6.i1.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 12/01/2015] [Accepted: 01/11/2016] [Indexed: 02/05/2023] Open
Abstract
Inadequate absorptive surface area poses a great challenge to the patients suffering a variety of intestinal diseases causing short bowel syndrome. To date, these patients are managed with total parenteral nutrition or intestinal transplantation. However, these carry significant morbidity and mortality. Currently, by emergence of tissue engineering, anticipations to utilize an alternative method to increase the intestinal absorptive surface area are increasing. In this paper, we will review the improvements made over time in attempting elongating the intestine with surgical techniques as well as using intestinal bioengineering. Performing sequential intestinal lengthening was the preliminary method applied in humans. However, these methods did not reach widespread use and has limited outcome. Subsequent experimental methods were developed utilizing scaffolds to regenerate intestinal tissue and organoids unit from the intestinal epithelium. Stem cells also have been studied and applied in all types of tissue engineering. Biomaterials were utilized as a structural support for naive cells to produce bio-engineered tissue that can achieve a near-normal anatomical structure. A promising novel approach is the elongation of the intestine with an acellular biologic scaffold to generate a neo-formed intestinal tissue that showed, for the first time, evidence of absorption in vivo. In the large intestine, studies are more focused on regeneration and engineering of sphincters and will be briefly reviewed. From the review of the existing literature, it can be concluded that significant progress has been achieved in these experimental methods but that these now need to be fully translated into a pre-clinical and clinical experimentation to become a future viable therapeutic option.
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446
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Bajaj P, Harris JF, Huang JH, Nath P, Iyer R. Advances and Challenges in Recapitulating Human Pulmonary Systems: At the Cusp of Biology and Materials. ACS Biomater Sci Eng 2016; 2:473-488. [PMID: 33465851 DOI: 10.1021/acsbiomaterials.5b00480] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The aim of this review is to provide an overview of physiologically relevant microengineered lung-on-a-chip (LoC) platforms for a variety of different biomedical applications with emphasis on drug screening. First, a brief outline of lung anatomy and physiology is presented followed by discussion of the lung parenchyma and its extracellular matrix. Next, we point out the technical challenges in recapitulating the complexity of lung in conventional static two-dimensional microenvironments and the need for alternate lung platforms. The importance of scaling laws is also emphasized in designing these in vitro microengineered lung platforms. The review then discusses current LoC platforms that have been used for testing the efficacy of drugs or as model systems for investigating disorders of the lung parenchyma. Finally, the design parameters in developing an ideal physiologically relevant LoC platform are presented. As this emerging field of organ-on-a-chip can serve an alternative platform for animal testing of drugs or modeling human diseases in vitro, it has significant potential to impact the future of pharmaceutical research.
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Affiliation(s)
- Piyush Bajaj
- Information Systems and Modeling, §Bioscience Division, and ⊥Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Jennifer F Harris
- Information Systems and Modeling, Bioscience Division, and ⊥Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Jen-Huang Huang
- Information Systems and Modeling, Bioscience Division, and Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Pulak Nath
- Information Systems and Modeling, Bioscience Division, and Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Rashi Iyer
- Information Systems and Modeling, Bioscience Division, and Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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447
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Schwerdtfeger LA, Ryan EP, Tobet SA. An organotypic slice model for ex vivo study of neural, immune, and microbial interactions of mouse intestine. Am J Physiol Gastrointest Liver Physiol 2016; 310:G240-8. [PMID: 26680736 PMCID: PMC4754739 DOI: 10.1152/ajpgi.00299.2015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 12/07/2015] [Indexed: 01/31/2023]
Abstract
Organotypic tissue slices provide seminatural, three-dimensional microenvironments for use in ex vivo study of specific organs and have advanced investigative capabilities compared with isolated cell cultures. Several characteristics of the gastrointestinal tract have made in vitro models for studying the intestine challenging, such as maintaining the intricate structure of microvilli, the intrinsic enteric nervous system, Peyer's patches, the microbiome, and the active contraction of gut muscles. In the present study, an organotypic intestinal slice model was developed that allows for functional investigation across regions of the intestine. Intestinal tissue slices were maintained ex vivo for several days in a physiologically relevant environment that preserved normal enterocyte structure, intact and proliferating crypt cells, submucosal organization, and muscle wall composure. Cell death was measured by a membrane-impermeable DNA binding indicator, ethidium homodimer, and less than 5% of cells were labeled in all regions of the villi and crypt epithelia at 24 h ex vivo. This tissue slice model demonstrated intact myenteric and submucosal neuronal plexuses and functional interstitial cells of Cajal to the extent that nonstimulated, segmental contractions occurred for up to 48 h ex vivo. To detect changes in physiological responses, slices were also assessed for segmental contractions in the presence and absence of antibiotic treatment, which resulted in slices with lesser or greater amounts of commensal bacteria, respectively. Segmental contractions were significantly greater in slices without antibiotics and increased native microbiota. This model renders mechanisms of neuroimmune-microbiome interactions in a complex gut environment available to direct observation and controlled perturbation.
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Affiliation(s)
- Luke A. Schwerdtfeger
- 1Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado;
| | - Elizabeth P. Ryan
- 3Department of Environmental & Radiological Health Sciences, Colorado State University, Fort Collins, Colorado
| | - Stuart A. Tobet
- 1Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado; ,2School of Biomedical Engineering, Colorado State University, Fort Collins, Colorado; and
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448
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Modeling Barrier Tissues In Vitro: Methods, Achievements, and Challenges. EBioMedicine 2016; 5:30-9. [PMID: 27077109 PMCID: PMC4816829 DOI: 10.1016/j.ebiom.2016.02.023] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 02/09/2016] [Accepted: 02/11/2016] [Indexed: 12/24/2022] Open
Abstract
Organ-on-a-chip devices have gained attention in the field of in vitro modeling due to their superior ability in recapitulating tissue environments compared to traditional multiwell methods. These constructed growth environments support tissue differentiation and mimic tissue-tissue, tissue-liquid, and tissue-air interfaces in a variety of conditions. By closely simulating the in vivo biochemical and biomechanical environment, it is possible to study human physiology in an organ-specific context and create more accurate models of healthy and diseased tissues, allowing for observations in disease progression and treatment. These chip devices have the ability to help direct, and perhaps in the distant future even replace animal-based drug efficacy and toxicity studies, which have questionable relevance to human physiology. Here, we review recent developments in the in vitro modeling of barrier tissue interfaces with a focus on the use of novel and complex microfluidic device platforms.
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449
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van der Helm MW, van der Meer AD, Eijkel JCT, van den Berg A, Segerink LI. Microfluidic organ-on-chip technology for blood-brain barrier research. Tissue Barriers 2016; 4:e1142493. [PMID: 27141422 PMCID: PMC4836466 DOI: 10.1080/21688370.2016.1142493] [Citation(s) in RCA: 201] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 12/28/2015] [Accepted: 01/02/2016] [Indexed: 12/25/2022] Open
Abstract
Organs-on-chips are a new class of microengineered laboratory models that combine several of the advantages of current in vivo and in vitro models. In this review, we summarize the advances that have been made in the development of organ-on-chip models of the blood-brain barrier (BBBs-on-chips) and the challenges that are still ahead. The BBB is formed by specialized e3ndothelial cells and separates blood from brain tissue. It protects the brain from harmful compounds from the blood and provides homeostasis for optimal neuronal function. Studying BBB function and dysfunction is important for drug development and biomedical research. Microfluidic BBBs-on-chips enable real-time study of (human) cells in an engineered physiological microenvironment, for example incorporating small geometries and fluid flow as well as sensors. Examples of BBBs-on-chips in literature already show the potential of more realistic microenvironments and the study of organ-level functions. A key challenge in the field of BBB-on-chip development is the current lack of standardized quantification of parameters such as barrier permeability and shear stress. This limits the potential for direct comparison of the performance of different BBB-on-chip models to each other and existing models. We give recommendations for further standardization in model characterization and conclude that the rapidly emerging field of BBB-on-chip models holds great promise for further studies in BBB biology and drug development.
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Affiliation(s)
- Marinke W van der Helm
- BIOS Lab on a Chip group, MIRA Institute for Biomedical Technology and Technical Medicine & MESA+ Institute for Nanotechnology, University of Twente ; Enschede, The Netherlands
| | - Andries D van der Meer
- Applied Stem Cell Technologies, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente ; Enschede, The Netherlands
| | - Jan C T Eijkel
- BIOS Lab on a Chip group, MIRA Institute for Biomedical Technology and Technical Medicine & MESA+ Institute for Nanotechnology, University of Twente ; Enschede, The Netherlands
| | - Albert van den Berg
- BIOS Lab on a Chip group, MIRA Institute for Biomedical Technology and Technical Medicine & MESA+ Institute for Nanotechnology, University of Twente ; Enschede, The Netherlands
| | - Loes I Segerink
- BIOS Lab on a Chip group, MIRA Institute for Biomedical Technology and Technical Medicine & MESA+ Institute for Nanotechnology, University of Twente ; Enschede, The Netherlands
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450
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Sochol RD, Gupta NR, Bonventre JV. A Role for 3D Printing in Kidney-on-a-Chip Platforms. CURRENT TRANSPLANTATION REPORTS 2016; 3:82-92. [PMID: 28090431 DOI: 10.1007/s40472-016-0085-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The advancement of "kidney-on-a-chip" platforms - submillimeter-scale fluidic systems designed to recapitulate renal functions in vitro - directly impacts a wide range of biomedical fields, including drug screening, cell and tissue engineering, toxicity testing, and disease modelling. To fabricate kidney-on-a-chip technologies, researchers have primarily adapted traditional micromachining techniques that are rooted in the integrated circuit industry; hence the term, "chip." A significant challenge, however, is that such methods are inherently monolithic, which limits one's ability to accurately recreate the geometric and architectural complexity of the kidney in vivo. Better reproduction of the anatomical complexity of the kidney will allow for more instructive modelling of physiological and pathophysiological events. Emerging additive manufacturing or "three-dimensional (3D) printing" techniques could provide a promising alternative to conventional methodologies. In this article, we discuss recent progress in the development of both kidney-on-a-chip platforms and state-of-the-art submillimeter-scale 3D printing methods, with a focus on biophysical and architectural capabilities. Lastly, we examine the potential for 3D printing-based approaches to extend the efficacy of kidney-on-a-chip systems.
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Affiliation(s)
- Ryan D Sochol
- Department of Mechanical Engineering, University of Maryland, College Park, MD
| | - Navin R Gupta
- Renal Division, Brigham and Women's Hospital, Department of Medicine, Harvard Medical School, Boston, MA
| | - Joseph V Bonventre
- Renal Division, Brigham and Women's Hospital, Department of Medicine, Harvard Medical School, Boston, MA; Harvard Stem Cell Institute, Cambridge, Massachusetts, USA
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