scholarly journals A phenomenological density-scaling approach to lamellipodial actin dynamics

2014 ◽  
Vol 4 (6) ◽  
pp. 20140006 ◽  
Author(s):  
Alexandre Lewalle ◽  
Marco Fritzsche ◽  
Kerry Wilson ◽  
Richard Thorogate ◽  
Tom Duke ◽  
...  
Keyword(s):  
Protein Function ◽  
Cell Types ◽  
Actin Dynamics ◽  
Theoretical Modelling ◽  
Network Growth ◽  
Genetic Intervention ◽  
Regulatory Processes ◽  
Observable Behaviour ◽  
Different Cell Types

The integration of protein function studied in vitro in a dynamic system like the cell lamellipodium remains a significant challenge. One reason is the apparent contradictory effect that perturbations of some proteins can have on the overall lamellipodium dynamics, depending on exact conditions. Theoretical modelling offers one approach for understanding the balance between the mechanisms that drive and regulate actin network growth and decay. Most models use a ‘bottom-up’ approach, involving explicitly assembling biochemical components to simulate observable behaviour. Their correctness therefore relies on both the accurate characterization of all the components and the completeness of the relevant processes involved. To avoid potential pitfalls due to this uncertainty, we used an alternative ‘top-down’ approach, in which measurable features of lamellipodium behaviour, here observed in two different cell types (HL60 and B16-F1), directly inform the development of a simple phenomenological model of lamellipodium dynamics. We show that the kinetics of F-actin association and dissociation scales with the local F-actin density, with no explicit location dependence. This justifies the use of a simplified kinetic model of lamellipodium dynamics that yields predictions testable by pharmacological or genetic intervention. A length-scale parameter (the lamellipodium width) emerges from this analysis as an experimentally accessible probe of network regulatory processes.

scholarly journals Therapeutic Attributes of Endocannabinoid System against Neuro-Inflammatory Autoimmune Disorders

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3389
Author(s):  
Ishtiaq Ahmed ◽  
Saif Ur Rehman ◽  
Shiva Shahmohamadnejad ◽  
Muhammad Anjum Zia ◽  
Muhammad Ahmad ◽  
...  
Keyword(s):  
Cannabinoid Receptors ◽  
Cannabinoid Receptor ◽  
Therapeutic Potential ◽  
Endocannabinoid System ◽  
Cell Types ◽  
Autoimmune Disorders ◽  
Specific Receptors ◽  
Different Cell Types

In humans, various sites like cannabinoid receptors (CBR) having a binding affinity with cannabinoids are distributed on the surface of different cell types, where endocannabinoids (ECs) and derivatives of fatty acid can bind. The binding of these substance(s) triggers the activation of specific receptors required for various physiological functions, including pain sensation, memory, and appetite. The ECs and CBR perform multiple functions via the cannabinoid receptor 1 (CB1); cannabinoid receptor 2 (CB2), having a key effect in restraining neurotransmitters and the arrangement of cytokines. The role of cannabinoids in the immune system is illustrated because of their immunosuppressive characteristics. These characteristics include inhibition of leucocyte proliferation, T cells apoptosis, and induction of macrophages along with reduced pro-inflammatory cytokines secretion. The review seeks to discuss the functional relationship between the endocannabinoid system (ECS) and anti-tumor characteristics of cannabinoids in various cancers. The therapeutic potential of cannabinoids for cancer—both in vivo and in vitro clinical trials—has also been highlighted and reported to be effective in mice models in arthritis for the inflammation reduction, neuropathic pain, positive effect in multiple sclerosis and type-1 diabetes mellitus, and found beneficial for treating in various cancers. In human models, such studies are limited; thereby, further research is indispensable in this field to get a conclusive outcome. Therefore, in autoimmune disorders, therapeutic cannabinoids can serve as promising immunosuppressive and anti-fibrotic agents.

scholarly journals Divergent functions of endotrophin on different cell populations in adipose tissue

2016 ◽  
Vol 311 (6) ◽  
pp. E952-E963 ◽  
Author(s):  
Yueshui Zhao ◽  
Xue Gu ◽  
Ningyan Zhang ◽  
Mikhail G. Kolonin ◽  
Zhiqiang An ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Lipid Accumulation ◽  
Lysyl Oxidase ◽  
Stromal Vascular Fraction ◽  
Cell Types ◽  
Marker Genes ◽  
New Perspective ◽  
Collagen Genes ◽  
Different Cell Types

Endotrophin is a cleavage product of collagen 6 (Col6) in adipose tissue (AT). Previously, we demonstrated that endotrophin serves as a costimulator to trigger fibrosis and inflammation within the unhealthy AT milieu. However, how endotrophin affects lipid storage and breakdown in AT and how different cell types in AT respond to endotrophin stimulation remain unknown. In the current study, by using a doxycycline-inducible mouse model, we observed significant upregulation of adipogenic genes in the white AT (WAT) of endotrophin transgenic mice. We further showed that the mice exhibited inhibited lipolysis and accelerated hypertrophy and hyperplasia in WAT. To investigate the effects of endotrophin in vitro, we incubated different cell types from AT with conditioned medium from endotrophin-overexpressing 293T cells. We found that endotrophin activated multiple pathological pathways in different cell types. Particularly in 3T3-L1 adipocytes, endotrophin triggered a fibrotic program by upregulating collagen genes and promoted abnormal lipid accumulation by downregulating hormone-sensitive lipolysis gene and decreasing HSL phosphorylation levels. In macrophages isolated from WAT, endotrophin stimulated higher expression of the collagen-linking enzyme lysyl oxidase and M1 proinflammatory marker genes. In the stromal vascular fraction isolated from WAT, endotrophin induced upregulation of both profibrotic and proinflammatory genes. In conclusion, our study provides a new perspective on the effect of endotrophin in abnormal lipid accumulation and a mechanistic insight into the roles played by adipocytes and a variety of other cell types in AT in shaping the unhealthy microenvironment upon endotrophin treatment.

Cultured epithelial cells derived from human foetal pancreas as a model for the study of cystic fibrosis: further analyses on the origins and nature of the cell types

1988 ◽  
Vol 90 (1) ◽  
pp. 73-77
Author(s):  
A. Harris ◽  
L. Coleman
Keyword(s):  
Cystic Fibrosis ◽  
Tissue Culture ◽  
Epithelial Cells ◽  
Culture System ◽  
Cultured Cells ◽  
Cell Types ◽  
Cultured Epithelial Cells ◽  
Different Cell Types ◽  
Foetal Pancreas

The establishment of a tissue-culture system for epithelial cells derived from human foetal pancreas has recently been reported. Further analyses have now been made on these cells in vitro, together with parallel investigation of the distribution of different cell types within the intact foetal pancreas. Results support the view that the cultured cells are ductal in origin and nature. Pancreatic epithelial cell cultures have also been established from foetuses with cystic fibrosis.

scholarly journals Bromodomain protein inhibition: a novel therapeutic strategy in rheumatic diseases

RMD Open ◽  
2018 ◽  
Vol 4 (2) ◽  
pp. e000744 ◽  
Author(s):  
Kerstin Klein
Keyword(s):  
Animal Models ◽  
Rheumatic Diseases ◽  
Transcriptional Activation ◽  
Therapeutic Strategy ◽  
Cell Types ◽  
Protein Inhibition ◽  
Different Cell Types ◽  
Novel Therapeutic

The reading of acetylation marks on histones by bromodomain (BRD) proteins is a key event in transcriptional activation. Small molecule inhibitors targeting bromodomain and extra-terminal (BET) proteins compete for binding to acetylated histones. They have strong anti-inflammatory properties and exhibit encouraging effects in different cell types in vitro and in animal models resembling rheumatic diseases in vivo. Furthermore, recent studies that focus on BRD proteins beyond BET family members are discussed.

scholarly journals Filopodyan: An open-source pipeline for the analysis of filopodia

2017 ◽  
Vol 216 (10) ◽  
pp. 3405-3422 ◽  
Author(s):  
Vasja Urbančič ◽  
Richard Butler ◽  
Benjamin Richier ◽  
Manuel Peter ◽  
Julia Mason ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Dynamic Properties ◽  
Cell Types ◽  
Molecular Heterogeneity ◽  
Interactive Editing ◽  
Motile Cells ◽  
Different Cell Types ◽  
Neuronal Growth Cones

Filopodia have important sensory and mechanical roles in motile cells. The recruitment of actin regulators, such as ENA/VASP proteins, to sites of protrusion underlies diverse molecular mechanisms of filopodia formation and extension. We developed Filopodyan (filopodia dynamics analysis) in Fiji and R to measure fluorescence in filopodia and at their tips and bases concurrently with their morphological and dynamic properties. Filopodyan supports high-throughput phenotype characterization as well as detailed interactive editing of filopodia reconstructions through an intuitive graphical user interface. Our highly customizable pipeline is widely applicable, capable of detecting filopodia in four different cell types in vitro and in vivo. We use Filopodyan to quantify the recruitment of ENA and VASP preceding filopodia formation in neuronal growth cones, and uncover a molecular heterogeneity whereby different filopodia display markedly different responses to changes in the accumulation of ENA and VASP fluorescence in their tips over time.

scholarly journals High-precision 3D inkjet technology for live cell bioprinting

2019 ◽  
Vol 5 (2) ◽  
pp. 27 ◽  
Author(s):  
Daisuke Takagi ◽  
Waka Lin ◽  
Takahiko Matsumoto ◽  
Hidekazu Yaginuma ◽  
Natsuko Hemmi ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Cell Types ◽  
Cell Number ◽  
Live Cell ◽  
Drop On Demand ◽  
Long Time ◽  
Spatial Positioning ◽  
Different Cell Types ◽  
Membrane Vibrations

In recent years, bioprinting has emerged as a promising technology for the construction of three-dimensional (3D) tissues to be used in regenerative medicine or in vitro screening applications. In the present study, we present the development of an inkjet-based bioprinting system to arrange multiple cells and materials precisely into structurally organized constructs. A novel inkjet printhead has been specially designed for live cell ejection. Droplet formation is powered by piezoelectric membrane vibrations coupled with mixing movements to prevent cell sedimentation at the nozzle. Stable drop-on-demand dispensing and cell viability were validated over an adequately long time to allow the fabrication of 3D tissues. Reliable control of cell number and spatial positioning was demonstrated using two separate suspensions with different cell types printed sequentially. Finally, a process for constructing stratified Mille-Feuille-like 3D structures is proposed by alternately superimposing cell suspensions and hydrogel layers with a controlled vertical resolution. The results show that inkjet technology is effective for both two-dimensional patterning and 3D multilayering and has the potential to facilitate the achievement of live cell bioprinting with an unprecedented level of precision.

A simple microcomputer-based system for real-time analysis of cell behaviour

1987 ◽  
Vol 87 (1) ◽  
pp. 171-182
Author(s):  
J.A. Dow ◽  
J.M. Lackie ◽  
K.V. Crocket
Keyword(s):  
Real Time ◽  
Search Algorithm ◽  
Cell Types ◽  
Real Time Analysis ◽  
Lighting Conditions ◽  
Previous Frame ◽  
Real Time Tracking ◽  
Cell Densities ◽  
Different Cell Types

An image analysis package based on a BBC microcomputer has been developed, which can simultaneously track many moving cells in vitro. Cells (rabbit neutrophil leucocytes, BHK C13 fibroblasts, or PC12 phaeochromocytoma cells) are viewed under phase optics with a monochrome TV camera, and the signal digitized. Successive frames are acquired by the computer as a 640 X 256 pixel array. Under controlled lighting conditions, cells can readily be isolated from the background by binary filtering. In real-time tracking, the positions of a given cell in successive frames are obtained by searching the area around the cell's centroid in the previous frame. A simple box-search algorithm is described, which proves highly successful at low cell densities. The resilience of different search algorithms to various exceptional conditions (such as collisions) is discussed. The success of this system in real-time tracking is largely dependent upon the leisurely speed of movement of cells, and on obtaining a clean, high quality optical image to analyse. The limitations of this technique for different cell types, and the possible configurations of more sophisticated hardware, are outlined. This system provides a versatile and automated solution to the problem of studying the movement of tissue cells.

Poly I:C stimulation in-vitro as a marker for an antiviral response in different cell types generated from Buffalo (Bubalus bubalis)

2020 ◽  
Vol 121 ◽  
pp. 136-143
Author(s):  
Ashutosh Vats ◽  
Devika Gautam ◽  
Jitendra Maharana ◽  
Jatinder Singh Chera ◽  
Sushil Kumar ◽  
...  
Keyword(s):  
Cell Types ◽  
Bubalus Bubalis ◽  
Antiviral Response ◽  
Poly I:C ◽  
Different Cell Types
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