scholarly journals Development of a stacked, porous silk scaffold neuroblastoma model for investigating spatial differences in cell and drug responsiveness

2021 ◽  
Author(s):  
Kimberly J. Ornell ◽  
Katelyn S. Mistretta ◽  
Coulter Q. Ralston ◽  
Jeannine M. Coburn
Keyword(s):  
Spatial Differences ◽  
Silk Scaffolds ◽  
Silk Scaffold ◽  
Drug Responsiveness ◽  
Spatial Cell

Stacked porous silk scaffolds support spatial, cell-driven changes in an in vitro neuroblastoma model.

P140 3D BIOENGINEERED TISSUE MODEL OF THE LARGE INTESTINE TO STUDY INFLAMMATORY BOWEL DISEASE

2020 ◽  
Vol 26 (Supplement_1) ◽  
pp. S34-S35
Author(s):  
Terrence Roh ◽  
Ying Chen ◽  
Harry Paul ◽  
Chengchen Guo ◽  
David Kaplan
Keyword(s):  
Inflammatory Bowel Disease ◽  
Large Intestine ◽  
Intestinal Epithelium ◽  
Bowel Disease ◽  
Tissue Model ◽  
Inflammatory Bowel ◽  
Silk Scaffold ◽  
Subepithelial Layer ◽  
Migration Of Macrophages

Abstract An in vitro model of intestine epithelium with an immune compartment was bioengineered to mimic immunologic responses seen in inflammatory bowel disease [1]. While aspects of intestinal immunity can be modeled in transwells and 2D culture systems, 3D tissue models improve physiological relevance by providing a 3D substrate which enable migration of macrophages towards the epithelium. An intestinal epithelium comprised of non-transformed human colon organoid cells and a subepithelial layer laden with monocyte-derived macrophages was bioengineered to mimic native intestinal mucosa cell organization using spongy silk scaffolds. Confluent epithelial monolayers with microvilli, a mucus layer, and infiltration of macrophages to the basal side of the epithelium were observed. Inflammation, induced by E. coli O111:B4 lipopolysaccharide and interferon γ resulted in morphology changes to the epithelium, resulting in ball-like structures, decreased epithelial coverage, and migration of macrophages to the epithelium. Analysis of cytokines present in the inflamed tissue model demonstrated significantly upregulated secretion of pro-inflammatory cytokines associated with active inflammatory bowel disease, including CXCL10, IL-1β, IL-6, MCP-2, and MIP-1β. The macrophage layer enhanced epithelial and biochemical responses to inflammatory stimuli, and this new tissue system may be useful to study and develop potential therapies for inflammatory bowel disease. References: 6 Roh, T.T., et al., 3D bioengineered tissue model of the large intestine to study inflammatory bowel disease. Biomaterials, 2019: p. 119517. 7 In, J., et al., Enterohemorrhagic Escherichia coli reduce mucus and intermicrovillar bridges in human stem cell-derived colonoids. Cellular and molecular gastroenterology and hepatology, 2015. 2(1): p. 48–62.e3. 8 Chen, Y., et al., In vitro enteroid-derived three-dimensional tissue model of human small intestinal epithelium with innate immune responses. PLoS ONE, 2017. 12(11): p. e0187880. Colonoid and macrophage cultivation scheme in the 3D bilayer system. (A) Human monocytes were isolated from whole blood and human colonoids from large intestine biopsies were cultured according to established protocols [2]. (B) Cell suspensions of colonoids were seeded on the film surface on the inner silk scaffold and monocyte-derived macrophages were seeded throughout the porous outer silk scaffold using established protocols [3]. (C) The model is cultured for 3 weeks total with 2 weeks in High WNT media and 1 week in differentiation media based on established protocol. Colonoids are present in the model throughout the 3 week culture time. 2 sets of macrophages are added with the first set added after the first week of culture and the second set replacing the first set after the second week.

Hierarchically porous nagelschmidtite bioceramic–silk scaffolds for bone tissue engineering

2015 ◽  
Vol 3 (18) ◽  
pp. 3799-3809 ◽  
Author(s):  
Mengchi Xu ◽  
Hong Li ◽  
Dong Zhai ◽  
Jiang Chang ◽  
Shiyi Chen ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Hierarchically Porous ◽  
Silk Scaffolds

Hierarchically bioceramic–silk scaffolds are composed of first-level pores (~1 mm) of bioceramic and second-level pores (∼50–100 μm) of silk matrix, showing improved in vitro and in vivo bioactivity.

VALIDATION OF THEIN VITROINCUBATION OF EXTENSOR DIGITORUM LONGUS MUSCLE FROM MICE WITH A MATHEMATICAL MODEL

2010 ◽  
Vol 18 (03) ◽  
pp. 687-707
Author(s):  
PETER SOGAARD ◽  
MIKAEL HARLÉN ◽  
YUN CHAU LONG ◽  
FERENC SZEKERES ◽  
BRIAN R. BARNES ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Experimental Method ◽  
Glycogen Content ◽  
Lactate Concentration ◽  
Lactate Production ◽  
Measuring Method ◽  
High Rate ◽  
Diabetes Research ◽  
Spatial Differences

In vitro incubation of tissues; in particular, skeletal muscles from rodents, is a widely-used experimental method in diabetes research. This experimental method has previously been validated, both experimentally and theoretically. However, much of the method's experimental data remains unclear, including the high-rate of lactate production and the lack of an observable increase in glycogen content, within a given time. The predominant hypothesis explaining the high-rate of lactate production is that this phenomenon is dependent on a mechanism in glycolysis that works as a safety valve, producing lactate when glucose uptake is super-physiological. Another hypothesis is that existing anoxia forces more ATP to be produced from glycolysis, leading to an increased lactate concentration. The lack of an observable increase in glycogen content is assumed to be dependent on limitations in sensitivity of the measuring method used. We derived a mathematical model to investigate which of these hypotheses is most likely to be correct. Using our model, data analysis indicates that the in vitro incubated muscle specimens, most likely are sensing the presence of existing anoxia, rather than an overflow in glycolysis. The anoxic milieu causes the high lactate production. The model also predicts an increased glycogenolysis. After mathematical analyses, an estimation of the glycogen concentration could be made with a reduced model. In conclusion, central anoxia is likely to cause spatial differences in glycogen concentrations throughout the entire muscle. Thus, data regarding total glycogen levels in the incubated muscle do not accurately represent the entire organ. The presented model allows for an estimation of total glycogen, despite spatial differences present in the muscle specimen.

scholarly journals Effect of Pore Size on the Biodegradation Rate of Silk Fibroin Scaffolds

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Zuwei Luo ◽  
Qin Zhang ◽  
Meijing Shi ◽  
Yang Zhang ◽  
Wei Tao ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Weight Loss ◽  
Pore Size ◽  
Silk Fibroin ◽  
Degradation Rate ◽  
Structural Integrity ◽  
Pore Density ◽  
Tissue Engineering Scaffolds ◽  
Silk Scaffolds

Controlling the degradation rate of silk fibroin-based biomaterial is an important capability for the fabrication of silk-based tissue engineering scaffolds. In this study, scaffolds with different pore sizes were prepared by controlling the freezing temperature and the silk fibroin concentration.In vitrodegradation results showed that the internal pore walls of the scaffolds with a larger pore size collapsed upon exposure to collagenase IA for times ranging from 6 to 12 days, and the silk scaffolds exhibited a faster rate of weight loss. The morphological and structural features of the silk scaffolds with a smaller pore size maintained structural integrity after incubation in the protease solution for 18 days, and the rate of weight loss was relatively slow. Scaffolds with a smaller pore size or a higher pore density degraded more slowly than scaffolds with a larger pore size or lower pore density. These results demonstrate that the pore size of silk biomaterials is crucial in controlling the degradation rate of tissue engineering scaffolds.

scholarly journals Enhanced BMP-2-Mediated Bone Repair Using an Anisotropic Silk Fibroin Scaffold Coated with Bone-like Apatite

2021 ◽  
Vol 23 (1) ◽  
pp. 283
Author(s):  
Christian Deininger ◽  
Andrea Wagner ◽  
Patrick Heimel ◽  
Elias Salzer ◽  
Xavier Monforte Vila ◽  
...  
Keyword(s):  
Bone Repair ◽  
Bone Morphogenetic Protein 2 ◽  
Great Promise ◽  
Calcium Phosphate Coating ◽  
Graft Material ◽  
Morphogenetic Protein ◽  
Silk Scaffolds ◽  
Cost Efficient

The repair of large bone defects remains challenging and often requires graft material due to limited availability of autologous bone. In clinical settings, collagen sponges loaded with excessive amounts of bone morphogenetic protein 2 (rhBMP-2) are occasionally used for the treatment of bone non-unions, increasing the risk of adverse events. Therefore, strategies to reduce rhBMP-2 dosage are desirable. Silk scaffolds show great promise due to their favorable biocompatibility and their utility for various biofabrication methods. For this study, we generated silk scaffolds with axially aligned pores, which were subsequently treated with 10× simulated body fluid (SBF) to generate an apatitic calcium phosphate coating. Using a rat femoral critical sized defect model (CSD) we evaluated if the resulting scaffold allows the reduction of BMP-2 dosage to promote efficient bone repair by providing appropriate guidance cues. Highly porous, anisotropic silk scaffolds were produced, demonstrating good cytocompatibility in vitro and treatment with 10× SBF resulted in efficient surface coating. In vivo, the coated silk scaffolds loaded with a low dose of rhBMP-2 demonstrated significantly improved bone regeneration when compared to the unmineralized scaffold. Overall, our findings show that this simple and cost-efficient technique yields scaffolds that enhance rhBMP-2 mediated bone healing.

scholarly journals Effect of Cellular and ECM Aging on Human iPSC-derived Cardiomyocyte Performance, Maturity and Senescence

2020 ◽  
Author(s):  
S. Gulberk Ozcebe ◽  
Gokhan Bahcecioglu ◽  
Xiaoshan S. Yue ◽  
Pinar Zorlutuna
Keyword(s):  
Cardiac Function ◽  
Cardiac Tissue ◽  
Induced Pluripotent Stem Cell ◽  
State Function ◽  
Cardiac Aging ◽  
Induced Pluripotent ◽  
The Individual ◽  
Drug Responsiveness ◽  
Tissue Aging

AbstractCardiovascular diseases are the leading cause of death worldwide and their occurrence is highly associated with age. However, lack of knowledge in cardiac tissue aging is a major roadblock in devising novel therapies. Here, we studied the effects of cell and cardiac extracellular matrix (ECM) aging on the induced pluripotent stem cell (iPSC)-derived cardiomyocyte cell state, function, as well as response to myocardial infarction (MI)-mimicking stress conditions in vitro. Within 3-weeks, young ECM promoted proliferation and drug responsiveness in young cells, and induced cell cycle re-entry, and protection against stress in the aged cells. Adult ECM improved cardiac function, while aged ECM accelerated the aging phenotype, and impaired cardiac function and stress defense machinery of the cells. In summary, we have gained a comprehensive understanding of cardiac aging and highlighted the importance of cell-ECM interactions. This study is the first to investigate the individual effects of cellular and environmental aging and identify the biochemical changes that occur upon cardiac aging.

scholarly journals Metabolically-Driven Maturation of hiPSC-Cell Derived Cardiac Chip

2018 ◽  
Author(s):  
Nathaniel Huebsch ◽  
Berenice Charrez ◽  
Brian Siemons ◽  
Steven C. Boggess ◽  
Samuel Wall ◽  
...  
Keyword(s):  
Pluripotent Stem Cell ◽  
Disease Modeling ◽  
Induced Pluripotent Stem Cell ◽  
Left Ventricular ◽  
Calcium Handling ◽  
Acid Oxidation ◽  
Microphysiological Systems ◽  
Induced Pluripotent ◽  
Drug Responsiveness

AbstractHuman induced pluripotent stem cell derived cardiomyocytes (hiPSC-CM) are a promising in vitro tool for drug development and disease modeling, but their immature electrophysiology limits diagnostic utility. Tissue engineering approaches involving aligned 3D cultures enhance hiPSC-CM structural maturation but are insufficient to induce mature electrophysiology. We hypothesized that mimicking post-natal switching of the heart’s primary ATP source from glycolysis to fatty acid oxidation could enhance electrophysiological maturation of hiPSC-CM. We combined hiPSC-CM with microfabricated culture chambers to form 3D cardiac microphysiological systems (MPS) that enhanced immediate microtissue alignment and tissue specific extracellular matrix (ECM) production. Using Robust Experimental design, we identified a maturation media that improved calcium handling in MPS derived from two genetically distinct hiPSC sources. Although calcium handling and metabolic maturation were improved in both genotypes, there was a divergent effect on action potential duration (APD): MPS that started with abnormally prolonged APD exhibited shorter APD in response to maturation media, whereas the same media prolonged the APD in MPS that started with aberrantly short APD. Importantly, the APD of both genotypes was brought near the range of 270-300ms observed in human left ventricular cardiomyocytes. Mathematical modeling explained these divergent phenotypes, and further predicted the response of matured MPS to drugs with known pro-arrhythmic effects. These results suggest that systematic combination of biophysical stimuli and metabolic cues can enhance the electrophysiological maturation of hiPSC-derived cardiomyocytes. However, they also reveal that maturation-inducing cues can have differential effects on electrophysiology depending on the baseline phenotype of hiPSC-CM. In silico models provide a valuable tool for predicting how changes in cellular maturation will manifest in drug responsiveness.

Abstract 2425: An in vitro platform to dissect drug responsiveness in refractory anemia with ringed sideroblasts (RARS)

2015 ◽  
Author(s):  
Daniela Georgieva ◽  
Sheherzad Preisler ◽  
Michael Churchill ◽  
Abdullah Mahmood Ali ◽  
Azra Raza ◽  
...  
Keyword(s):  
Refractory Anemia ◽  
Ringed Sideroblasts ◽  
Drug Responsiveness
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