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

Micromachines ◽  
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.

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

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.

scholarly journals Merging Microfluidics with Microtitre Technology for More Efficient Drug Discovery

2008 ◽  
Vol 13 (5) ◽  
pp. 275-279 ◽  
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.

scholarly journals Graded regulation of cellular quiescence depth between proliferation and senescence by a lysosomal dimmer switch

2019 ◽  
Vol 116 (45) ◽  
pp. 22624-22634 ◽  
Author(s):  
Kotaro Fujimaki ◽  
Ruoyan Li ◽  
Hengyu Chen ◽  
Kimiko Della Croce ◽  
Hao Helen Zhang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Expression Signature ◽  
Cell Types ◽  
The Body ◽  
Cellular Mechanisms ◽  
Lysosomal Function ◽  
Quiescent Cells ◽  
Common Transition

The reactivation of quiescent cells to proliferate is fundamental to tissue repair and homeostasis in the body. Often referred to as the G0 state, quiescence is, however, not a uniform state but with graded depth. Shallow quiescent cells exhibit a higher tendency to revert to proliferation than deep quiescent cells, while deep quiescent cells are still fully reversible under physiological conditions, distinct from senescent cells. Cellular mechanisms underlying the control of quiescence depth and the connection between quiescence and senescence are poorly characterized, representing a missing link in our understanding of tissue homeostasis and regeneration. Here we measured transcriptome changes as rat embryonic fibroblasts moved from shallow to deep quiescence over time in the absence of growth signals. We found that lysosomal gene expression was significantly up-regulated in deep quiescence, and partially compensated for gradually reduced autophagy flux. Reducing lysosomal function drove cells progressively deeper into quiescence and eventually into a senescence-like irreversibly arrested state; increasing lysosomal function, by lowering oxidative stress, progressively pushed cells into shallower quiescence. That is, lysosomal function modulates graded quiescence depth between proliferation and senescence as a dimmer switch. Finally, we found that a gene-expression signature developed by comparing deep and shallow quiescence in fibroblasts can correctly classify a wide array of senescent and aging cell types in vitro and in vivo, suggesting that while quiescence is generally considered to protect cells from irreversible arrest of senescence, quiescence deepening likely represents a common transition path from cell proliferation to senescence, related to aging.

scholarly journals The Tuberculous Granuloma: An Unsuccessful Host Defence Mechanism Providing a Safety Shelter for the Bacteria?

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Mayra Silva Miranda ◽  
Adrien Breiman ◽  
Sophie Allain ◽  
Florence Deknuydt ◽  
Frederic Altare
Keyword(s):  
Cell Types ◽  
Giant Cells ◽  
The Body ◽  
Differentiated Cells ◽  
Latently Infected ◽  
Long Time ◽  
Infectious Stage ◽  
Different Cell Types

One of the main features of the immune response toM. Tuberculosisis the formation of an organized structure called granuloma. It consists mainly in the recruitment at the infectious stage of macrophages, highly differentiated cells such as multinucleated giant cells, epithelioid cells and Foamy cells, all these cells being surrounded by a rim of lymphocytes. Although in the first instance the granuloma acts to constrain the infection, some bacilli can actually survive inside these structures for a long time in a dormant state. For some reasons, which are still unclear, the bacilli will reactivate in 10% of the latently infected individuals, escape the granuloma and spread throughout the body, thus giving rise to clinical disease, and are finally disseminated throughout the environment. In this review we examine the process leading to the formation of the granulomatous structures and the different cell types that have been shown to be part of this inflammatory reaction. We also discuss the differentin vivoandin vitromodels available to study this fascinating immune structure.

scholarly journals The neural crest stem cells: control of neural crest cell fate and plasticity by endothelin-3

2001 ◽  
Vol 73 (4) ◽  
pp. 533-545 ◽  
Author(s):  
ELISABETH DUPIN ◽  
CARLA REAL ◽  
NICOLE LeDOUARIN
Keyword(s):  
Stem Cells ◽  
Neural Crest ◽  
Cell Fate ◽  
Neural Crest Cell ◽  
Cell Types ◽  
The Body ◽  
Neural Crest Stem Cells ◽  
Environmental Signals

How the considerable diversity of neural crest (NC)-derived cell types arises in the vertebrate embryo has long been a key question in developmental biology. The pluripotency and plasticity of differentiation of the NC cell population has been fully documented and it is well-established that environmental cues play an important role in patterning the NC derivatives throughout the body. Over the past decade, in vivo and in vitro cellular approaches have unravelled the differentiation potentialities of single NC cells and led to the discovery of NC stem cells. Although it is clear that the final fate of individual cells is in agreement with their final position within the embryo, it has to be stressed that the NC cells that reach target sites are pluripotent and further restrictions occur only late in development. It is therefore a heterogenous collection of cells that is submitted to local environmental signals in the various NC-derived structures. Several factors were thus identified which favor the development of subsets of NC-derived cells in vitro. Moreover, the strategy of gene targeting in mouse has led at identifying new molecules able to control one or several aspects of NC cell differentiation in vivo. Endothelin peptides (and endothelin receptors) are among those. The conjunction of recent data obtained in mouse and avian embryos and reviewed here contributes to a better understanding of the action of the endothelin signaling pathway in the emergence and stability of NC-derived cell phenotypes.

Cell Patterning: Interaction of Cardiac Myocytes and Fibroblasts in Three-Dimensional Culture

2008 ◽  
Vol 14 (2) ◽  
pp. 117-125 ◽  
Author(s):  
Troy A. Baudino ◽  
Alex McFadden ◽  
Charity Fix ◽  
Joshua Hastings ◽  
Robert Price ◽  
...  
Keyword(s):  
Cardiac Tissue ◽  
Three Dimensional ◽  
Normal Growth ◽  
Cell Types ◽  
Cell Interactions ◽  
Cellular Interactions ◽  
Cell Layers ◽  
Cell Cell

Patterning of cells is critical to the formation and function of the normal organ, and it appears to be dependent upon internal and external signals. Additionally, the formation of most tissues requires the interaction of several cell types. Indeed, both extracellular matrix (ECM) components and cellular components are necessary for three-dimensional (3-D) tissue formationin vitro. Using 3-D cultures we demonstrate that ECM arranged in an aligned fashion is necessary for the rod-shaped phenotype of the myocyte, and once this pattern is established, the myocytes were responsible for the alignment of any subsequent cell layers. This is analogous to thein vivopattern that is observed, where there appears to be minimal ECM signaling, rather formation of multicellular patterns is dependent upon cell–cell interactions. Our 3-D culture of myocytes and fibroblasts is significant in that it modelsin vivoorganization of cardiac tissue and can be used to investigate interactions between fibroblasts and myocytes. Furthermore, we used rotational cultures to examine cellular interactions. Using these systems, we demonstrate that specific connexins and cadherins are critical for cell–cell interactions. The data presented here document the feasibility of using these systems to investigate cellular interactions during normal growth and injury.

scholarly journals Dismantling Cell–Cell Contacts during Apoptosis Is Coupled to a Caspase-dependent Proteolytic Cleavage of β-Catenin

1997 ◽  
Vol 139 (3) ◽  
pp. 759-771 ◽  
Author(s):  
Claudio Brancolini ◽  
Dean Lazarevic ◽  
Joe Rodriguez ◽  
Claudio Schneider
Keyword(s):  
Cell Death ◽  
Cell Adhesion ◽  
Actin Cytoskeleton ◽  
Caspase 3 ◽  
Cell Types ◽  
Cell Contacts ◽  
Carboxy Terminal ◽  
Cell Cell

Cell death by apoptosis is a tightly regulated process that requires coordinated modification in cellular architecture. The caspase protease family has been shown to play a key role in apoptosis. Here we report that specific and ordered changes in the actin cytoskeleton take place during apoptosis. In this context, we have dissected one of the first hallmarks in cell death, represented by the severing of contacts among neighboring cells. More specifically, we provide demonstration for the mechanism that could contribute to the disassembly of cytoskeletal organization at cell–cell adhesion. In fact, β-catenin, a known regulator of cell–cell adhesion, is proteolytically processed in different cell types after induction of apoptosis. Caspase-3 (cpp32/apopain/yama) cleaves in vitro translated β-catenin into a form which is similar in size to that observed in cells undergoing apoptosis. β-Catenin cleavage, during apoptosis in vivo and after caspase-3 treatment in vitro, removes the amino- and carboxy-terminal regions of the protein. The resulting β-catenin product is unable to bind α-catenin that is responsible for actin filament binding and organization. This evidence indicates that connection with actin filaments organized at cell–cell contacts could be dismantled during apoptosis. Our observations suggest that caspases orchestrate the specific and sequential changes in the actin cytoskeleton occurring during cell death via cleavage of different regulators of the microfilament system.

Endogenous Expression of Functional Factor VIII by Human Mesenchymal Stem Cells In Culture

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2216-2216
Author(s):  
Chad Sanada ◽  
Evan J Colletti ◽  
Melisa Soland ◽  
Chung-Jung Kuo ◽  
Christopher D Porada ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Liver Failure ◽  
Cell Types ◽  
The Body ◽  
Rt Pcr ◽  
Fviii Activity ◽  
Innate Ability

Abstract Abstract 2216 The liver is considered to be the primary site of factor VIII (FVIII) production in the body; however, evidence is mounting that suggests there are secondary sites in which considerable synthesis of FVIII takes place. Studies of FVIII mRNA expression in various human tissues have revealed that FVIII message can be found throughout the body. Additionally, acute liver failure correlates with an increase in circulating FVIII levels. Some reports have identified endothelial cells as a significant extra-hepatic source of FVIII, possibly explaining both the widespread presence of FVIII mRNA and the increase in FVIII levels upon liver failure. However, the possibility exists that other cell types present throughout the body also produce FVIII and contribute to circulating FVIII levels. Mesenchymal Stem Cells (MSCs) represent a potential alternative; they are a diverse group of stromal cells which can be found in the perivascular regions of multiple tissues throughout the body. Previous studies demonstrated that MSCs are capable of efficiently producing and secreting high levels of FVIII in vitro when transduced with FVIII-encoding viral vectors, but to date, the innate ability of MSCs to produce FVIII has not been explored. As such, we investigated the potential for MSCs to produce endogenous FVIII message and secrete functional protein. MSCs isolated based on Stro-1 positivity from human lung, liver, brain, and bone marrow (BM) were grown in cell culture and assayed for production of FVIII message by both microarray analysis and RT-PCR. Microarray data showed that there were significant amounts of FVIII message in all four cell types tested and that the amount of message in BM MSCs was three-fold higher than each of the other three cell types. RT-PCR analysis confirmed the presence of FVIII message in all four MSC populations. Secretion of functional FVIII protein was subsequently measured using a chromogenic assay. MSC culture supernatants were collected for either 24 or 48 hours, and FVIII activity was determined using pooled normal human plasma as a control to create a standard curve. FVIII activity in the supernatants of MSCs was in the range of 0.6 to 2.0 mU/1×10^6 cells/ 24hr. Moreover, MSCs continued to express and produce FVIII during time in culture until our last evaluation at passage 20, indicating that there is an innate ability of these cells to continually produce FVIII. Taken together, these data demonstrate that human MSCs are capable of producing and secreting functional FVIII in vitro, and given their widespread location throughout the body, this finding raises the possibility that, in vivo, these cells might significantly contribute to the total FVIII pool. This is the first report, to our knowledge, that implicates MSCs as a potential endogenous source for circulating FVIII. Further studies of in vivo FVIII expression by MSCs are warranted and may provide a clearer understanding of extra-hepatic FVIII production in the body while aiding in the discovery of novel therapies for hemophilia A. Disclosures: No relevant conflicts of interest to declare.

scholarly journals A strategy for tissue self-organization that is robust to cellular heterogeneity and plasticity

2015 ◽  
Vol 112 (7) ◽  
pp. 2287-2292 ◽  
Author(s):  
Alec E. Cerchiari ◽  
James C. Garbe ◽  
Noel Y. Jee ◽  
Michael E. Todhunter ◽  
Kyle E. Broaders ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Cell Types ◽  
Cell Interaction ◽  
Cellular Heterogeneity ◽  
Self Organization ◽  
Cell Contact ◽  
Cell Type ◽  
Interfacial Energies ◽  
Cell Cell

Developing tissues contain motile populations of cells that can self-organize into spatially ordered tissues based on differences in their interfacial surface energies. However, it is unclear how self-organization by this mechanism remains robust when interfacial energies become heterogeneous in either time or space. The ducts and acini of the human mammary gland are prototypical heterogeneous and dynamic tissues comprising two concentrically arranged cell types. To investigate the consequences of cellular heterogeneity and plasticity on cell positioning in the mammary gland, we reconstituted its self-organization from aggregates of primary cells in vitro. We find that self-organization is dominated by the interfacial energy of the tissue–ECM boundary, rather than by differential homo- and heterotypic energies of cell–cell interaction. Surprisingly, interactions with the tissue–ECM boundary are binary, in that only one cell type interacts appreciably with the boundary. Using mathematical modeling and cell-type-specific knockdown of key regulators of cell–cell cohesion, we show that this strategy of self-organization is robust to severe perturbations affecting cell–cell contact formation. We also find that this mechanism of self-organization is conserved in the human prostate. Therefore, a binary interfacial interaction with the tissue boundary provides a flexible and generalizable strategy for forming and maintaining the structure of two-component tissues that exhibit abundant heterogeneity and plasticity. Our model also predicts that mutations affecting binary cell–ECM interactions are catastrophic and could contribute to loss of tissue architecture in diseases such as breast cancer.

scholarly journals Tubular structures in S49 mouse lymphoma are regulated through in vivo host-cell interaction and in vitro interferon treatment.

1985 ◽  
Vol 100 (5) ◽  
pp. 1351-1356 ◽  
Author(s):  
J Hochman ◽  
N Mador ◽  
A Panet
Keyword(s):  
Immunohistochemical Analysis ◽  
Cell Types ◽  
Cell Interaction ◽  
Tubular Structures ◽  
Tumorigenic Potential ◽  
Tumor Virus ◽  
Viruslike Particles ◽  
Mouse Lymphoma

Malignant S49 mouse lymphoma cells that grow in suspension culture demonstrate in their cytoplasm characteristic tubular structures. These structures also appear in immunogenic, substrate-adherent variants of S49 cells that grow in culture. Upon transfer of both cell types into nude mice, the tubular structures of the adherent variants (and not the suspension-growing cells) undergo a profound alteration whereby their tubular components disappear and clusters of viruslike particles appear. These very closely resemble, on morphological grounds, precursors of B-type retroviruses. This specific in vivo interaction between the host and the S49 variant can be mimicked in culture by treatment of these cells for 24 h with 500 U/ml of mouse interferon. The suspension-growing S49 cells are unresponsive to interferon in this respect. Immunohistochemical analysis reveals that both tubular structures and the viruslike particles represent stages in the morphogenesis of mouse mammary tumor virus. A working hypothesis is advanced relating the regulation of the tubular system to the impaired tumorigenic potential of adherent S49 cells in syngeneic Balb/c hosts.

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