Faculty Opinions recommendation of Cell dynamics during somite boundary formation revealed by time-lapse analysis.

Abstract The introduction of time-lapse imaging to clinical in vitro fertilization practice enabled the undisturbed monitoring of embryos throughout the entire culture period. Initially, the main objective was to achieve a better embryo development. However, this technology also provided an insight into the novel concept of morphokinetics, parameters regarding embryo cell dynamics. The vast amount of data obtained defined the optimal ranges in the cell-cycle lengths at different stages of embryo development. This added valuable information to embryo assessment prior to transfer. Kinetic markers became part of embryo evaluation strategies with the potential to increase the chances of clinical success. However, none of them has been established as an international standard. The present work aims at describing new approaches into time-lapse: progress to date, challenges, and possible future directions.

Download Full-text

An Easy-to-Fabricate Cell Stretcher Reveals Density-Dependent Mechanical Regulation of Collective Cell Movements in Epithelia

Cellular and Molecular Bioengineering ◽

10.1007/s12195-021-00689-6 ◽

2021 ◽

Author(s):

Kevin C. Hart ◽

Joo Yong Sim ◽

Matthew A. Hopcroft ◽

Daniel J. Cohen ◽

Jiongyi Tan ◽

...

Keyword(s):

Low Cost ◽

Cell Movement ◽

Time Lapse ◽

Adherent Cell ◽

Dependent Manner ◽

Cell Dynamics ◽

Density Dependent ◽

Cell Movements ◽

Tissue Biology ◽

Mechanical Regulation

Abstract Introduction Mechanical forces regulate many facets of cell and tissue biology. Studying the effects of forces on cells requires real-time observations of single- and multi-cell dynamics in tissue models during controlled external mechanical input. Many of the existing devices used to conduct these studies are costly and complicated to fabricate, which reduces the availability of these devices to many laboratories. Methods We show how to fabricate a simple, low-cost, uniaxial stretching device, with readily available materials and instruments that is compatible with high-resolution time-lapse microscopy of adherent cell monolayers. In addition, we show how to construct a pressure controller that induces a repeatable degree of stretch in monolayers, as well as a custom MATLAB code to quantify individual cell strains. Results As an application note using this device, we show that uniaxial stretch slows down cellular movements in a mammalian epithelial monolayer in a cell density-dependent manner. We demonstrate that the effect on cell movement involves the relocalization of myosin downstream of Rho-associated protein kinase (ROCK). Conclusions This mechanical device provides a platform for broader involvement of engineers and biologists in this important area of cell and tissue biology. We used this device to demonstrate the mechanical regulation of collective cell movements in epithelia.

Download Full-text

An Easy-to-Fabricate Cell Stretching System Reveals Density-Dependent Mechanical Regulation of Collective Cell Movements in Epithelial Homeostasis

10.1101/2020.08.24.265629 ◽

2020 ◽

Author(s):

Kevin C. Hart ◽

Joo Yong Sim ◽

Matthew A. Hopcroft ◽

Daniel J. Cohen ◽

Jiongyi Tan ◽

...

Keyword(s):

Low Cost ◽

Time Lapse ◽

Adherent Cell ◽

Dependent Manner ◽

Cell Dynamics ◽

Density Dependent ◽

Cell Monolayers ◽

Epithelial Homeostasis ◽

Tissue Biology ◽

A Cell

AbstractMechanical forces regulate many facets of tissue biology. Studying the effects of forces on cells requires real-time observations of single- and multi-cell dynamics in tissue models during controlled external mechanical input. Many of the existing devices used to conduct these studies are costly and complicated to fabricate, which reduces the availability of these devices to many laboratories. In this report, we show how to fabricate a simple, low-cost uniaxial stretching device with readily available materials and instruments that is compatible with high-resolution time-lapse microscopy of adherent cell monolayers. In addition, we show how to construct a pressure controller that induces a repeatable degree of stretch in monolayers, and a custom MATLAB code to quantify individual cell strains. Finally, as an application note using this device, we show that uniaxial stretch slows down cellular movements in an epithelial monolayer in a cell density-dependent manner that involves the relocalization of myosin downstream of Rho-associated protein kinase (ROCK). This mechanical device provides a platform for broader involvement of engineers and biologists in this important area of tissue biology.

Download Full-text

An immobilization technique for long-term time-lapse imaging of explanted Drosophila tissues

10.1101/2020.08.04.234864 ◽

2020 ◽

Author(s):

Matthew P. Bostock ◽

Anadika R. Prasad ◽

Rita Chaouni ◽

Alice C. Yuen ◽

Rita Sousa-Nunes ◽

...

Keyword(s):

Time Lapse ◽

Tissue Level ◽

Anisotropic Pressure ◽

Biological Processes ◽

Effective Technique ◽

Cell Dynamics ◽

First Instar ◽

Stress Damage ◽

Time Lapse Imaging

AbstractTime-lapse imaging is an essential tool to study dynamic biological processes that cannot be discerned from fixed samples alone. However, imaging cell- and tissue-level processes in intact animals poses numerous challenges if the organism is opaque and/or motile. Explant cultures of intact tissues circumvent some of these challenges, but sample drift remains a considerable obstacle. We employed a simple yet effective technique to immobilize tissues in medium-bathed agarose. We applied this technique to study multiple Drosophila tissues from first-instar larvae to adult stages in various orientations and with no evidence of anisotropic pressure or stress damage. Using this method, we were able to image fine features for up to 18 hours and make novel observations. Specifically, we report that fibers characteristic of quiescent neuroblasts are inherited by their basal daughters during reactivation; that the lamina in the developing visual system is assembled roughly 2-3 columns at a time; that lamina glia positions are dynamic during development; and that the nuclear envelopes of adult testis cyst stem cells do not break down completely during mitosis. In all, we demonstrate that our protocol is well-suited for tissue immobilization and long-term live imaging, enabling new insights into tissue and cell dynamics in Drosophila.

Download Full-text

TissueMiner: A multiscale analysis toolkit to quantify how cellular processes create tissue dynamics

eLife ◽

10.7554/elife.14334 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 53

Author(s):

Raphaël Etournay ◽

Matthias Merkel ◽

Marko Popović ◽

Holger Brandl ◽

Natalie A Dye ◽

...

Keyword(s):

Multiscale Analysis ◽

Time Lapse ◽

Convergent Extension ◽

Cell Dynamics ◽

Computational Framework ◽

Cellular Processes ◽

Multi Scale ◽

Pupal Wing ◽

Shape Changes

Segmentation and tracking of cells in long-term time-lapse experiments has emerged as a powerful method to understand how tissue shape changes emerge from the complex choreography of constituent cells. However, methods to store and interrogate the large datasets produced by these experiments are not widely available. Furthermore, recently developed methods for relating tissue shape changes to cell dynamics have not yet been widely applied by biologists because of their technical complexity. We therefore developed a database format that stores cellular connectivity and geometry information of deforming epithelial tissues, and computational tools to interrogate it and perform multi-scale analysis of morphogenesis. We provide tutorials for this computational framework, called TissueMiner, and demonstrate its capabilities by comparing cell and tissue dynamics in vein and inter-vein subregions of the Drosophila pupal wing. These analyses reveal an unexpected role for convergent extension in shaping wing veins.

Download Full-text

Acquiring Fluorescence Time-lapse Movies of Budding Yeast and Analyzing Single-cell Dynamics using GRAFTS

Journal of Visualized Experiments ◽

10.3791/50456 ◽

2013 ◽

Cited By ~ 1

Author(s):

Christopher J. Zopf ◽

Narendra Maheshri

Keyword(s):

Single Cell ◽

Budding Yeast ◽

Time Lapse ◽

Cell Dynamics

Download Full-text

A simple and flexible computational framework for inferring sources of heterogeneity from single-cell dynamics

10.1101/341867 ◽

2018 ◽

Cited By ~ 1

Author(s):

Lekshmi Dharmarajan ◽

Hans-Michael Kaltenbach ◽

Fabian Rudolf ◽

Joerg Stelling

Keyword(s):

Single Cell ◽

Single Cell Analysis ◽

Mechanistic Model ◽

Time Lapse ◽

Data Sets ◽

Multiple Sources ◽

Nonlinear Mixed Effects Models ◽

Cell Dynamics ◽

Important Open Problem ◽

Microscopy Data

AbstractThe availability of high-resolution single-cell data makes data analysis and interpretation an important open problem, for example, to disentangle sources of cell-to-cell and intra-cellular variability. Nonlinear mixed effects models (NLMEs), well established in pharmacometrics, account for such multiple sources of variations, but their estimation is often difficult. Single-cell analysis is an even more challenging application with larger data sets and models that are more complicated. Here, we show how to leverage the quality of time-lapse microscopy data with a simple two-stage method to estimate realistic dynamic NLMEs accurately. We demonstrate accuracy by benchmarking with a published model and dataset, and scalability with a new mechanistic model and corresponding dataset for amino acid transporter endocytosis in budding yeast. We also propose variation-based sensitivity analysis to identify time-dependent causes of cell-to-cell variability, highlighting important sub-processes in endocytosis. Generality and simplicity of the approach will facilitate customized extensions for analyzing single-cell dynamics.

Download Full-text

Long-term time-lapse multimodal microscopy for tracking cell dynamics in live tissue

10.1117/12.874183 ◽

2011 ◽

Cited By ~ 2

Author(s):

Benedikt W. Graf ◽

Maria C. Valero ◽

Eric J. Chaney ◽

Marina Marjanovic ◽

Marni D. Boppart ◽

...

Keyword(s):

Time Lapse ◽

Cell Dynamics ◽

Live Tissue

Download Full-text

Long-term time-lapse multimodal intravital imaging of regeneration and bone-marrow-derived cell dynamics in skin

TECHNOLOGY ◽

10.1142/s2339547813500027 ◽

2013 ◽

Vol 01 (01) ◽

pp. 8-19 ◽

Cited By ~ 10

Author(s):

Benedikt W. Graf ◽

Eric J. Chaney ◽

Marina Marjanovic ◽

Steven G. Adie ◽

Michael De Lisio ◽

...

Keyword(s):

Bone Marrow ◽

Cell Biology ◽

Fluorescent Protein ◽

Time Lapse ◽

Great Promise ◽

Cell Dynamics ◽

Registration Method ◽

Long Time ◽

Green Fluorescent

A major challenge for translating cell-based therapies is understanding the dynamics of cells and cell populations in complex in vivo environments. Intravital microscopy has shown great promise for directly visualizing cell behavior in vivo. However, current methods are limited to relatively short imaging times (hours), by ways to track cell and cell population dynamics over extended time-lapse periods (days to weeks to months), and by relatively few imaging contrast mechanisms that persist over extended investigations. We present technology to visualize and quantify complex, multifaceted dynamic changes in natural deformable skin over long time periods using novel multimodal imaging and a non-rigid image registration method. These are demonstrated in green fluorescent protein (GFP) bone marrow (BM) transplanted mice to study dynamic skin regeneration. This technology provides a novel perspective for studying dynamic biological processes and will enable future studies of stem, immune, and tumor cell biology in vivo.

Download Full-text