Klotho inhibits neuronal senescence in human brain organoids

AbstractAging is a major risk factor for many neurodegenerative diseases. Klotho (KL) is a glycosylated transmembrane protein that is expressed in the choroid plexus and neurons of the brain. KL exerts potent anti-aging effects on multiple cell types in the body but its role in human brain cells remains largely unclear. Here we show that human cortical neurons, derived from human pluripotent stem cells in 2D cultures or in cortical organoids, develop the typical hallmarks of senescent cells when maintained in vitro for prolonged periods of time, and that moderate upregulation or repression of endogenous KL expression in cortical organoids inhibits and accelerates senescence, respectively. We further demonstrate that KL expression alters the expression of senescence-associated genes including, extracellular matrix genes, and proteoglycans, and can act in a paracrine fashion to inhibit neuronal senescence. In summary, our results establish an important role for KL in the regulation of human neuronal senescence and offer new mechanistic insight into its role in human brain aging.

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Downregulation of amyloid precursor protein inhibits neurite outgrowth in vitro.

The Journal of Cell Biology ◽

10.1083/jcb.128.5.919 ◽

1995 ◽

Vol 128 (5) ◽

pp. 919-927 ◽

Cited By ~ 165

Author(s):

B Allinquant ◽

P Hantraye ◽

P Mailleux ◽

K Moya ◽

C Bouillot ◽

...

Keyword(s):

Amyloid Precursor Protein ◽

Cortical Neurons ◽

Antisense Oligonucleotides ◽

Transmembrane Protein ◽

Morphological Differentiation ◽

Cell Types ◽

Precursor Protein ◽

Direct Access ◽

Developing Neurons

The amyloid precursor protein (APP) is a transmembrane protein expressed in several cell types. In the nervous system, APP is expressed by glial and neuronal cells, and several lines of evidence suggest that it plays a role in normal and pathological phenomena. To address the question of the actual function of APP in normal developing neurons, we undertook a study aimed at blocking APP expression using antisense oligonucleotides. Oligonucleotide internalization was achieved by linking them to a vector peptide that translocates through biological membranes. This original technique, which is very efficient and gives direct access to the cell cytosol and nucleus, allowed us to work with extracellular oligonucleotide concentrations between 40 and 200 nM. Internalization of antisense oligonucleotides overlapping the origin of translation resulted in a marked but transient decrease in APP neosynthesis that was not observed with the vector peptide alone, or with sense oligonucleotides. Although transient, the decrease in APP neosynthesis was sufficient to provoke a distinct decrease in axon and dendrite outgrowth by embryonic cortical neurons developing in vitro. The latter decrease was not accompanied by changes in the spreading of the cell bodies. A single exposure to coupled antisense oligonucleotides at the onset of the culture was sufficient to produce significant morphological effects 6, 18, and 24 h later, but by 42 h, there were no remaining significant morphologic changes. This report thus demonstrates that amyloid precursor protein plays an important function in the morphological differentiation of cortical neurons in primary culture.

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MyD88 Is Not Required for Muscle Injury-Induced Endochondral Heterotopic Ossification in a Mouse Model of Fibrodysplasia Ossificans Progressiva

Biomedicines ◽

10.3390/biomedicines9060630 ◽

2021 ◽

Vol 9 (6) ◽

pp. 630

Author(s):

Huili Lyu ◽

Cody M. Elkins ◽

Jessica L. Pierce ◽

C. Henrique Serezani ◽

Daniel S. Perrien

Keyword(s):

Heterotopic Ossification ◽

Muscle Injury ◽

Cell Types ◽

Fibrodysplasia Ossificans Progressiva ◽

Inflammatory Signaling ◽

Conditional Deletion ◽

Pathway Crosstalk ◽

Multiple Cell

Excess inflammation and canonical BMP receptor (BMPR) signaling are coinciding hallmarks of the early stages of injury-induced endochondral heterotopic ossification (EHO), especially in the rare genetic disease fibrodysplasia ossificans progressiva (FOP). Multiple inflammatory signaling pathways can synergistically enhance BMP-induced Smad1/5/8 activity in multiple cell types, suggesting the importance of pathway crosstalk in EHO and FOP. Toll-like receptors (TLRs) and IL-1 receptors mediate many of the earliest injury-induced inflammatory signals largely via MyD88-dependent pathways. Thus, the hypothesis that MyD88-dependent signaling is required for EHO was tested in vitro and in vivo using global or Pdgfrα-conditional deletion of MyD88 in FOP mice. As expected, IL-1β or LPS synergistically increased Activin A (ActA)-induced phosphorylation of Smad 1/5 in fibroadipoprogenitors (FAPs) expressing Alk2R206H. However, conditional deletion of MyD88 in Pdgfrα-positive cells of FOP mice did not significantly alter the amount of muscle injury-induced EHO. Even more surprisingly, injury-induced EHO was not significantly affected by global deletion of MyD88. These studies demonstrate that MyD88-dependent signaling is dispensable for injury-induced EHO in FOP mice.

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Comparative AAV-eGFP Transgene Expression Using Vector Serotypes 1–9, 7m8, and 8b in Human Pluripotent Stem Cells, RPEs, and Human and Rat Cortical Neurons

Stem Cells International ◽

10.1155/2019/7281912 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Thu T. Duong ◽

James Lim ◽

Vidyullatha Vasireddy ◽

Tyler Papp ◽

Hung Nguyen ◽

...

Keyword(s):

Cortical Neurons ◽

Transgene Expression ◽

Fluorescent Protein ◽

Ex Vivo ◽

Cell Types ◽

Egfp Expression ◽

Cell Type ◽

Egfp Gene ◽

Rat Cortical Neurons

Recombinant adeno-associated virus (rAAV), produced from a nonpathogenic parvovirus, has become an increasing popular vector for gene therapy applications in human clinical trials. However, transduction and transgene expression of rAAVs can differ acrossin vitroand ex vivo cellular transduction strategies. This study compared 11 rAAV serotypes, carrying one reporter transgene cassette containing a cytomegalovirus immediate-early enhancer (eCMV) and chicken beta actin (CBA) promoter driving the expression of an enhanced green-fluorescent protein (eGFP) gene, which was transduced into four different cell types: human iPSC, iPSC-derived RPE, iPSC-derived cortical, and dissociated embryonic day 18 rat cortical neurons. Each cell type was exposed to three multiplicity of infections (MOI: 1E4, 1E5, and 1E6 vg/cell). After 24, 48, 72, and 96 h posttransduction, GFP-expressing cells were examined and compared across dosage, time, and cell type. Retinal pigmented epithelium showed highest AAV-eGFP expression and iPSC cortical the lowest. At an MOI of 1E6 vg/cell, all serotypes show measurable levels of AAV-eGFP expression; moreover, AAV7m8 and AAV6 perform best across MOI and cell type. We conclude that serotype tropism is not only capsid dependent but also cell type plays a significant role in transgene expression dynamics.

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Clock gene-independent daily regulation of haemoglobin oxidation in red blood cells

10.1101/2021.10.11.463714 ◽

2021 ◽

Author(s):

Andrew D. Beale ◽

Priya Crosby ◽

Utham K. Valekunja ◽

Rachel S. Edgar ◽

Johanna E. Chesham ◽

...

Keyword(s):

Circadian Rhythms ◽

Red Blood Cells ◽

Blood Cells ◽

Human Subjects ◽

Developmental Regulation ◽

Physiological Role ◽

Cell Types ◽

The Body

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.

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Modulating cell state to enhance suspension expansion of human pluripotent stem cells

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1714099115 ◽

2018 ◽

Vol 115 (25) ◽

pp. 6369-6374 ◽

Cited By ~ 12

Author(s):

Yonatan Y. Lipsitz ◽

Curtis Woodford ◽

Ting Yin ◽

Jacob H. Hanna ◽

Peter W. Zandstra

Keyword(s):

Stem Cells ◽

Pluripotent Stem Cells ◽

Large Scale ◽

Cell Types ◽

Human Pluripotent Stem Cells ◽

The Body ◽

Altered Expression ◽

Pancreatic Progenitors ◽

Erk Inhibition

The development of cell-based therapies to replace missing or damaged tissues within the body or generate cells with a unique biological activity requires a reliable and accessible source of cells. Human pluripotent stem cells (hPSC) have emerged as a strong candidate cell source capable of extended propagation in vitro and differentiation to clinically relevant cell types. However, the application of hPSC in cell-based therapies requires overcoming yield limitations in large-scale hPSC manufacturing. We explored methods to convert hPSC to alternative states of pluripotency with advantageous bioprocessing properties, identifying a suspension-based small-molecule and cytokine combination that supports increased single-cell survival efficiency, faster growth rates, higher densities, and greater expansion than control hPSC cultures. ERK inhibition was found to be essential for conversion to this altered state, but once converted, ERK inhibition led to a loss of pluripotent phenotype in suspension. The resulting suspension medium formulation enabled hPSC suspension yields 5.7 ± 0.2-fold greater than conventional hPSC in 6 d, for at least five passages. Treated cells remained pluripotent, karyotypically normal, and capable of differentiating into all germ layers. Treated cells could also be integrated into directed differentiated strategies as demonstrated by the generation of pancreatic progenitors (NKX6.1+/PDX1+ cells). Enhanced suspension-yield hPSC displayed higher oxidative metabolism and altered expression of adhesion-related genes. The enhanced bioprocess properties of this alternative pluripotent state provide a strategy to overcome cell manufacturing limitations of hPSC.

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TMOD-21. A NOVEL IN-VITRO METHOD TO MODEL MACROPHAGES IN GLIOBLASTOMA

Neuro-Oncology ◽

10.1093/neuonc/noab196.882 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi220-vi220

Author(s):

Hasan Alrefai ◽

Andee Beierle ◽

Lauren Nassour ◽

Nicholas Eustace ◽

Zeel Patel ◽

...

Keyword(s):

Cell Types ◽

In Vitro Models ◽

Tumor Initiating Cells ◽

Serum Free ◽

Brain Tumor Initiating Cells ◽

Multiple Cell ◽

Anti Inflammatory ◽

Free Media ◽

Inflammatory Macrophages

Abstract BACKGROUND The GBM tumor microenvironment (TME) is comprised of a plethora of cancerous and non-cancerous cells that contribute to GBM growth, invasion, and chemoresistance. In-vitro models of GBM typically fail to incorporate multiple cell types. Others have addressed this problem by employing 3D bioprinting to incorporate astrocytes and macrophages in an extracellular matrix; however, they used serum-containing media and classically polarized anti-inflammatory macrophages. Serum has been shown to cause GBM brain-tumor initiating cells to lose their stem-like properties, highlighting the importance of excluding it from these models. Additionally, tumor-associated macrophages (TAMs) do not adhere to the traditional M2 phenotype. METHODS THP-1 monocytes and normal human astrocytes (NHAs) were transitioned into serum-free HL-1 and neurobasal-based media, respectively. Monocytes were stimulated towards a macrophage-like state with PMA and polarized by co-culturing them with GBM patient-derived xenograft(PDX) lines, using a transwell insert. CD206 expression was used to validate polarization and a cytokine array was used to characterize the cells. RESULTS There was no difference in proliferation rates at 72 hours for THP-1 monocytes grown in serum-free HL-1 media compared to serum-containing RPMI 1640 (p > 0.95). Macrophages polarized via transwell inserts expressed the lymphocyte chemoattractant protein, CCL2, whereas resting(M0), pro-inflammatory(M1), and anti-inflammatory(M2) macrophages did not. Additionally, these macrophages expressed more CXCL1 and IL-1ß relative to M1 macrophages. We have also demonstrated a method to maintain a tri-culture model of GBM PDX cells, NHAs, and TAMs in a serum-free media that supports the growth/maintenance of all cell types. CONCLUSIONS We have demonstrated a novel method by which we can polarize macrophages towards a tumor-supportive phenotype that differs in cytokine expression from traditionally polarized macrophages. This higher-fidelity method of modeling TAMs in GBM can aid in the development of targeted therapeutics that may one day enter the clinic in hopes of improving outcomes in GBM.

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OOCHIP: Compartmentalized Microfluidic Perfusion System with Porous Barriers for Enhanced Cell–Cell Crosstalk in Organ-on-a-Chip

Micromachines ◽

10.3390/mi11060565 ◽

2020 ◽

Vol 11 (6) ◽

pp. 565

Author(s):

Qasem Ramadan ◽

Sajay Bhuvanendran Nair Gourikutty ◽

Qingxin Zhang

Keyword(s):

Drug Efficacy ◽

Human Adipose Tissue ◽

Cell Types ◽

Cell Interaction ◽

The Body ◽

Close Proximity ◽

Porous Barriers ◽

Cell Cell

Improved in vitro models of human organs for predicting drug efficacy, interactions, and disease modelling are crucially needed to minimize the use of animal models, which inevitably display significant differences from the human disease state and metabolism. Inside the body, cells are organized either in direct contact or in close proximity to other cell types in a tightly controlled architecture that regulates tissue function. To emulate this cellular interface in vitro, an advanced cell culture system is required. In this paper, we describe a set of compartmentalized silicon-based microfluidic chips that enable co-culturing several types of cells in close proximity with enhanced cell–cell interaction. In vivo-like fluid flow into and/or from each compartment, as well as between adjacent compartments, is maintained by micro-engineered porous barriers. This porous structure provides a tool for mimicking the paracrine exchange between cells in the human body. As a demonstrating example, the microfluidic system was tested by culturing human adipose tissue that is infiltrated with immune cells to study the role if the interplay between the two cells in the context of type 2 diabetes. However, the system provides a platform technology for mimicking the structure and function of single- and multi-organ models, which could significantly narrow the gap between in vivo and in vitro conditions.

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Mesenchymal Stem Cells as a Promising Cell Source for Integration in Novel In Vitro Models

Biomolecules ◽

10.3390/biom10091306 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1306

Author(s):

Ann-Kristin Afflerbach ◽

Mark D. Kiri ◽

Tahir Detinis ◽

Ben M. Maoz

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Cell Types ◽

In Vitro Models ◽

Cell Source ◽

Fundamental Research ◽

Multiple Cell ◽

Vitro Model

The human-relevance of an in vitro model is dependent on two main factors—(i) an appropriate human cell source and (ii) a modeling platform that recapitulates human in vivo conditions. Recent years have brought substantial advancements in both these aspects. In particular, mesenchymal stem cells (MSCs) have emerged as a promising cell source, as these cells can differentiate into multiple cell types, yet do not raise the ethical and practical concerns associated with other types of stem cells. In turn, advanced bioengineered in vitro models such as microfluidics, Organs-on-a-Chip, scaffolds, bioprinting and organoids are bringing researchers ever closer to mimicking complex in vivo environments, thereby overcoming some of the limitations of traditional 2D cell cultures. This review covers each of these advancements separately and discusses how the integration of MSCs into novel in vitro platforms may contribute enormously to clinical and fundamental research.

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Three-dimensional testicular organoids as novel in vitro models of testicular biology and toxicology

Environmental Epigenetics ◽

10.1093/eep/dvz011 ◽

2019 ◽

Vol 5 (3) ◽

Cited By ~ 2

Author(s):

Sadman Sakib ◽

Anna Voigt ◽

Taylor Goldsmith ◽

Ina Dobrinski

Keyword(s):

Reproductive Biology ◽

Monolayer Culture ◽

Three Dimensional ◽

Cell Types ◽

In Vitro Models ◽

Toxicity Screening ◽

Current State ◽

Potential Applications ◽

Multiple Cell

Abstract Organoids are three dimensional structures consisting of multiple cell types that recapitulate the cellular architecture and functionality of native organs. Over the last decade, the advent of organoid research has opened up many avenues for basic and translational studies. Following suit of other disciplines, research groups working in the field of male reproductive biology have started establishing and characterizing testicular organoids. The three-dimensional architectural and functional similarities of organoids to their tissue of origin facilitate study of complex cell interactions, tissue development and establishment of representative, scalable models for drug and toxicity screening. In this review, we discuss the current state of testicular organoid research, their advantages over conventional monolayer culture and their potential applications in the field of reproductive biology and toxicology.

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Merging Microfluidics with Microtitre Technology for More Efficient Drug Discovery

JALA Journal of the Association for Laboratory Automation ◽

10.1016/j.jala.2008.05.002 ◽

2008 ◽

Vol 13 (5) ◽

pp. 275-279 ◽

Cited By ~ 2

Author(s):

Nicole V. Tolan ◽

Luiza I. Genes ◽

Dana M. Spence

Keyword(s):

Cellular Response ◽

Simultaneous Detection ◽

Drug Efficacy ◽

Cell Types ◽

Microtitre Plate ◽

Multiple Components ◽

Multiple Cell ◽

Improve Blood Flow

Detecting multiple components from a single red blood cell (RBC) sample within a flow-based system in less than 20 min will enable improved in vitro determinations of drug efficacy and cellular response to administered drugs. Here, an example of an improved in vitro measurement involving iloprost, a pharmaceutical reported to improve blood flow, has been determined by incorporating multiple cell types onto a single device. The method allows fluid flow to address individual rows of wells contained within an 18-well microfluidic array that serves as a precursor to a 96-well microtitre plate device. The ability to better mimic the in vivo circulation by incorporating the flow of blood components, coupled with simultaneous detection and laboratory automation in place for microtitre plates, suggests that the microfluidic array presented here will allow for improved mechanistic drug research studies. Using fluorescence microscopy, concentrations of multiple metabolites present within the RBC can also be determined using the microfluidic array. The current progress toward using this device for personalized medicine is presented here.

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