Enhanced microvasculature formation and patterning in iPSC-derived kidney organoids cultured in physiological hypoxia

2021 ◽  
Author(s):  
Anika Schumacher ◽  
Nadia Roumans ◽  
Timo Rademakers ◽  
Virginie Joris ◽  
Maria Jose Eischen-Loges ◽  
...  
Keyword(s):  
Pluripotent Stem Cells ◽  
Three Dimensional ◽  
Culture Conditions ◽  
End Stage Kidney Disease ◽  
Whole Mount ◽  
Factor Expression ◽  
Induced Pluripotent ◽  
End Stage ◽  
Kidney Organoids

Functional kidney organoids have the potential to be used in implantable kidney grafts for patients with end-stage kidney disease, because they have been shown to self-organize from induced pluripotent stem cells into most important renal structures. To date, however, long-term kidney organoid culture has not succeeded, as nephrons lose their phenotype after approximately 25 days. Furthermore, the renal structures remain immature with diminishing endothelial networks with low connectivity and limited organoid invasion. We hypothesized that introducing long-term culture at physiological hypoxia, rather than the normally applied non-physiological, hyperoxic 21% O2, could initiate angiogenesis, lead to enhanced growth factor expression and improve the endothelial patterning. We therefore cultured the kidney organoids at 7% O2 instead of 21% O2 for up to 25 days and evaluated nephrogenesis, VEGF-A expression and vascularization. Whole mount imaging revealed a homogenous morphology of the endothelial network with enhanced sprouting and interconnectivity when the kidney organoids were cultured in hypoxia. Three-dimensional quantification confirmed that the hypoxic culture led to an increased average vessel length, likely due to the observed upregulation of proangiogenic VEGF-A189 mRNA and downregulation of the antiangiogenic protein VEGF-A165b measured in hypoxia. This research indicates the importance of optimization of oxygen availability in organoid systems and the potential of hypoxic culture conditions in improving the vascularization of organoids.

scholarly journals Circulating re-entrant waves promote maturation of hiPSC-derived cardiomyocytes in self-organized tissue ring

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Junjun Li ◽  
Lu Zhang ◽  
Leqian Yu ◽  
Itsunari Minami ◽  
Shigeru Miyagawa ◽  
...  
Keyword(s):  
Pluripotent Stem Cells ◽  
Consumption Rate ◽  
Three Dimensional ◽  
Specific Gene ◽  
Directed Differentiation ◽  
Self Organized ◽  
Induced Pluripotent ◽  
Electrical Pacing ◽  
Long Term Behavior

AbstractDirected differentiation methods allow acquisition of high-purity cardiomyocytes differentiated from human induced pluripotent stem cells (hiPSCs); however, their immaturity characteristic limits their application for drug screening and regenerative therapy. The rapid electrical pacing of cardiomyocytes has been used for efficiently promoting the maturation of cardiomyocytes, here we describe a simple device in modified culture plate on which hiPSC-derived cardiomyocytes can form three-dimensional self-organized tissue rings (SOTRs). Using calcium imaging, we show that within the ring, reentrant waves (ReWs) of action potential spontaneously originated and ran robustly at a frequency up to 4 Hz. After 2 weeks, SOTRs with ReWs show higher maturation including structural organization, increased cardiac-specific gene expression, enhanced Ca2+-handling properties, an increased oxygen-consumption rate, and enhanced contractile force. We subsequently use a mathematical model to interpret the origination, propagation, and long-term behavior of the ReWs within the SOTRs.

scholarly journals Maintenance and Neuronal Differentiation of Chicken Induced Pluripotent Stem-Like Cells

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Rui Dai ◽  
Ricardo Rossello ◽  
Chun-chun Chen ◽  
Joeran Kessler ◽  
Ian Davison ◽  
...  
Keyword(s):  
Stem Cells ◽  
Neuronal Differentiation ◽  
Pluripotent Stem Cells ◽  
Vocal Learning ◽  
Culture Conditions ◽  
Differentiated Cells ◽  
Induced Pluripotent ◽  
Stem Cell State

Pluripotent stem cells have the potential to become any cell in the adult body, including neurons and glia. Avian stem cells could be used to study questions, like vocal learning, that would be difficult to examine with traditional mouse models. Induced pluripotent stem cells (iPSCs) are differentiated cells that have been reprogrammed to a pluripotent stem cell state, usually using inducing genes or other molecules. We recently succeeded in generating avian iPSC-like cells using mammalian genes, overcoming a limitation in the generation and use of iPSCs in nonmammalian species (Rosselló et al., 2013). However, there were no established optimal cell culture conditions for avian iPSCs to establish long-term cell lines and thus to study neuronal differentiationin vitro. Here we present an efficient method of maintaining chicken iPSC-like cells and for differentiating them into action potential generating neurons.

scholarly journals Fertility and Pregnancy in End Stage Kidney Failure Patients and after Renal Transplantation: An Update

2021 ◽  
Vol 2 (2) ◽  
pp. 92-108
Author(s):  
Maurizio Salvadori ◽  
Aris Tsalouchos
Keyword(s):  
Renal Transplantation ◽  
Time Lapse ◽  
Sexual Life ◽  
End Stage Kidney Disease ◽  
Correct Evaluation ◽  
Functional Aspects ◽  
Long Term Follow Up ◽  
End Stage

Sexual life and fertility are compromised in end stage kidney disease both in men and in women. Successful renal transplantation may rapidly recover fertility in the vast majority of patients. Pregnancy modifies anatomical and functional aspects in the kidney and represents a risk of sensitization that may cause acute rejection. Independently from the risks for the graft, pregnancy in kidney transplant may cause preeclampsia, gestational diabetes, preterm delivery, and low birth weight. The nephrologist has a fundamental role in correct counseling, in a correct evaluation of the mother conditions, and in establishing a correct time lapse between transplantation and conception. Additionally, careful attention must be given to the antirejection therapy, avoiding drugs that could be dangerous to the newborn. Due to the possibility of medical complications during pregnancy, a correct follow-up should be exerted. Even if pregnancy in transplant is considered a high risk one, several data and studies document that in the majority of patients, the long-term follow-up and outcomes for the graft may be similar to that of non-pregnant women.

scholarly journals Strategy to Establish Embryo-Derived Pluripotent Stem Cells in Cattle

2021 ◽  
Vol 22 (9) ◽  
pp. 5011
Author(s):  
Daehwan Kim ◽  
Sangho Roh
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Embryonic Stem Cells ◽  
Induced Pluripotent Stem Cells ◽  
Stem Cell Research ◽  
Pluripotent Stem Cells ◽  
Embryonic Stem ◽  
Culture Conditions ◽  
Human Diseases ◽  
Induced Pluripotent

Stem cell research is essential not only for the research and treatment of human diseases, but also for the genetic preservation and improvement of animals. Since embryonic stem cells (ESCs) were established in mice, substantial efforts have been made to establish true ESCs in many species. Although various culture conditions were used to establish ESCs in cattle, the capturing of true bovine ESCs (bESCs) has not been achieved. In this review, the difficulty of establishing bESCs with various culture conditions is described, and the characteristics of proprietary induced pluripotent stem cells and extended pluripotent stem cells are introduced. We conclude with a suggestion of a strategy for establishing true bESCs.

Age dependence of brachial cuff-based ambulatory PWV in end-stage kidney disease patients undergoing long-term peritoneal dialysis

2021 ◽  
pp. 089686082199692
Author(s):  
Vasilios Vaios ◽  
Panagiotis I Georgianos ◽  
Georgia Vareta ◽  
Dimitrios Divanis ◽  
Evangelia Dounousi ◽  
...  
Keyword(s):  
Risk Factors ◽  
Blood Pressure ◽  
Heart Rate ◽  
Peritoneal Dialysis ◽  
Kidney Disease ◽  
Pulse Wave ◽  
Age Dependence ◽  
End Stage Kidney Disease ◽  
End Stage

Background: The newly introduced device Mobil-O-Graph (IEM, Stolberg, Germany) combines brachial cuff oscillometry and pulse wave analysis, enabling the determination of pulse wave velocity (PWV) via complex mathematic algorithms during 24-h ambulatory blood pressure monitoring (ABPM). However, the determinants of oscillometric PWV in the end-stage kidney disease (ESKD) population remain poorly understood. Methods: In this study, 81 ESKD patients undergoing long-term peritoneal dialysis underwent 24-h ABPM with the Mobil-O-Graph device. The association of 24-h oscillometric PWV with several demographic, clinical and haemodynamic parameters was explored using linear regression analysis. Results: In univariate analysis, among 21 risk factors, 24-h PWV exhibited a positive relationship with age, body mass index, overhydration assessed via bioimpedance spectroscopy, diabetic status, history of dyslipidaemia and coronary heart disease, and it had a negative relationship with female sex and 24-h heart rate. In stepwise multivariate analysis, age ( β: 0.883), 24-h systolic blood pressure (BP) ( β: 0.217) and 24-h heart rate ( β: −0.083) were the only three factors that remained as independent determinants of 24-h PWV (adjusted R 2 = 0.929). These associations were not modified when all 21 risk factors were analysed conjointly or when the model included only variables shown to be significant in univariate comparisons. Conclusion: The present study shows that age together with simultaneously assessed oscillometric BP and heart rate are the major determinants of Mobil-O-Graph-derived PWV, explaining >90% of the total variation of this marker. This age dependence of oscillometric PWV limits the validity of this marker to detect the premature vascular ageing, a unique characteristic of vascular remodelling in ESKD.

scholarly journals Novel hybrid three-dimensional artificial liver using human induced pluripotent stem cells and a rat decellularized liver scaffold

2019 ◽  
Vol 10 ◽  
pp. 127-133 ◽  
Author(s):  
Takahito Minami ◽  
Takamichi Ishii ◽  
Kentaro Yasuchika ◽  
Ken Fukumitsu ◽  
Satoshi Ogiso ◽  
...  
Keyword(s):  
Stem Cells ◽  
Induced Pluripotent Stem Cells ◽  
Pluripotent Stem Cells ◽  
Three Dimensional ◽  
Artificial Liver ◽  
Induced Pluripotent ◽  
Decellularized Liver

scholarly journals Development of Multilayer Mesenchymal Stem Cell Cell Sheets

2021 ◽  
Vol 1 (1) ◽  
pp. 4-24
Author(s):  
Jun Ochiai ◽  
Yutaka Niihara ◽  
Joan Oliva
Keyword(s):  
Stem Cells ◽  
Stromal Cells ◽  
Pluripotent Stem Cells ◽  
Cell Sheets ◽  
Gene Therapies ◽  
The Past ◽  
Long Term Effect ◽  
Induced Pluripotent ◽  
New Guidelines

Cell and gene therapies have been developing dramatically over the past decade. To face and adapt to the development of these new therapies, the Food and Drug Administration (FDA) wrote and updated new guidelines from 2016 and keep updating them. Mesenchymal stem cells (MSCs) are the most used cells for treatment, far ahead from the induced pluripotent stem cells (iPSCs), based on registered clinical trials at clinicaltrials.gov. They are widely used because of their differentiation capacity and their anti-inflammatory properties, but some controversies still require clear answers. Additional studies are needed to determine the dosage, the number, and the route of injections (location and transplantation method), and if allogenic MSCs are safe compared to autologous MSC injection, including their long-term effect. In this review, we summarize the research our company is conducting with the adipose stromal cells in engineering cell sheets and their potential application.

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