Fluid Shear Stress-Induced Alignment of Cultured Vascular Smooth Muscle Cells

Lee, Ann A.; Graham, Dionne A.; Cruz, Sheila Dela; Ratcliffe, Anthony; Karlon, William J.

doi:10.1115/1.1427697

Cited by 103 publications

(106 citation statements)

References 39 publications

Supporting

Mentioning

101

Contrasting

Order By: Relevance

“…Out of all these various approaches, it has been found that the approaches giving results close to the true value are Huang, Li and BEAS, with the BEAS being the most effective than other two 31 . Furthermore, BEAS method is reportedly having more advantages and reliability than many automated methods such as Fast Fourier Transform-Radial Sum 38 (FFTRS) and gradient-based approaches 39 . The later ones are not able to give good results even for perfectly aligned cells.…”

Section: Thresholdingmentioning

confidence: 99%

Extracting Cell and Fibre Orientation from Microscopic Images:Computational Methods and Tools

Sharma

2016

Current Science

View full text Add to dashboard Cite

Orientation of cell and its actin fibres dictate various properties of the cell and its associated tissue including morphology, cell migration and response of cell to external stimuli. While the vital role of cell and actin fibre orientation has been demonstrated in various studies and across many cell-types, extracting this information from microscopy images is a challenging task. Although several methods have been developed to quantify alignment of a cell and its actin fibres from experimental images, all of them differ at one step or the other. We highlight the importance of orientation of cell and associated fibres and present a generic scheme of various approaches to assimilate the widely used methods. We have presented a systematic approach to determine cell and fibre orientation. The study will improve our understanding of the core processes and will also help in development of high throughput imaging methods to extract information from experimental images.Keywords: BEAS, cell orientation, DFT, fibre orientation, FFT, image processing, thresholding.IN the study of biological phenomena, cell is at a very fundamental level, as it is the smallest building block of all organisms. In fact, it is the smallest form of life that exhibits all the basic traits that form life such as birth, ingestion, digestion, protection and finally death. Cell during its life cycle experiences a number of mechanical interactions with surrounding environment necessary for its communication, proliferation, differentiation and migration [1][2][3][4][5][6][7][8] . A cell responds to these mechanical forces by exhibiting changes at various levels such as in morphology, protein synthesis 9,10 , gene expression 11,12 , etc. Then, cell tries to adapt to its environment through these changes. Several of its mechanical properties facilitate the adaptation of cell to the associated environment. Therefore, to understand the mechanism of working of a cell, knowledge of its mechanical properties and how do these get affected by a cell's surrounding environment is very vital. Microscopy-based imaging and its subsequent analysis is one of the traditional and widely used approaches to gain insights into the cell's mechanical and morphological properties. While microscopy imaging is a widely used approach to extract quantitative information about cell morphology, image analysis and morphology quantification are still challenging. One of the morphological features of a cell, which has been shown to exhibit several genotypic and phenotypic properties of a cell is the orientation of the cell. Similarly, orientation of fibres has been shown to exhibit various properties of associated cell population, including their density, topography, etc.The orientation of cell and the associated fibres are the indicative of many physiological and disease conditions. While microscopy-based image acquisition is the traditional method to gain insights into the orientation and morphology of cell and associated fibres, extracting thequantitative information about the c...

show abstract

Section: Thresholdingmentioning

confidence: 99%

Extracting Cell and Fibre Orientation from Microscopic Images:Computational Methods and Tools

Sharma

2016

Current Science

View full text Add to dashboard Cite

show abstract

“…Due to its significance in cellular response, there have been many studies on the effect of shear stress on EC and SMC orientation and development [25,26,42,45,86]. It has been shown that shear stress affects the phenotypic behavior of the individual vascular cells, and as a result, alters the macroscopic characteristics of blood vessels and their responses to diseases [37,46,74,83,89].…”

Section: Importance Of Wall Shear Stressmentioning

confidence: 99%

“…Lee et al investigated the effects of shear stress on cell and stress fiber orientation in smooth muscle cells (SMCs) isolated from the coronary arteries of dogs [42]. They also aimed to determine the magnitude of shear and time required to illicit cellular responses in order to gain an understanding of the mechanism that drives this response [42].…”

Section: Effects Of Shear Stress On Blood Vessel Physiologymentioning

confidence: 99%

“…Proper phenotypic expression and alignment of vascular cells is significantly dictated by the shear forces experienced by the cells and therefore, the characteristics of flow within the vessel [37,42,45,48,74,76,86]. Shear stress aids in regulating phenotype by altering gene expression, which results in changes in the release of growth factors and adhesion molecules [45].…”

Section: Effects Of Shear Stress On Blood Vessel Physiologymentioning

confidence: 99%

“…As described in Chapter 1, wall shear stress experienced by the endothelial cells of blood vessels can have a profound effect on nearly every aspect of the vessel: cell phenotype, cell orientation, and even development and progression of certain diseases and conditions [37,42,45,48,74,76,86]. Before presenting the methods and results of this work, it is necessary to discuss some basic principles of shear stress in fluid flow, the physiologic importance of shear stress, the level of shear required to produce desired effects, the methods by which other groups have implemented shear stress in their systems, and the concept behind developing the desired shear stress in our model.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Implementation of Physiologic Flow Conditions in a Blood Vessel Mimic Bioreactor System for the Evaluation of Intravascular Devices

Dawson¹

View full text Add to dashboard Cite

The prevalence and devastating nature of cardiovascular diseases has led to many advancements in the therapies used to treat the millions of patients that suffer as a result of these conditions. As coronary artery disease (CAD) is the most common of these cardiovascular conditions, it is a major focus of research among the medical industry.Although lifestyle changes and drug therapies can treat early CAD, more advanced cases often require more definitive interventions. In conjunction with angioplasty, stenting of an occluded vessel has shown significant success in preventing restenosis. However, as with nearly every therapeutic process in the medical field, several complications have arisen in stented patients that pose a need for further improvement of the devices. As a result, the stent industry is constantly striving towards improving the characteristics and outcome of their product and with these efforts comes the need for extensive testing and research.Continuous improvement and innovation in the field of tissue engineering has brought about the possibility of creating laboratory grown tissue engineered vascular grafts (TEVGs) for the purpose of replacing and/or bypassing damaged or occluded v regions of the vasculature. By employing the techniques used to produce TEVGs, a blood vessel mimic (BVM) bioreactor system has been developed with the intent of using the resulting construct as a model for testing the cellular response of a human blood vessel to an intravascular device such as a stent. This would allow gathering of more significant data in the early stages of device development and may reduce the overall costs and time required to refine a design.Although the BVM system has previously been used to cultivate viable constructs that were subsequently used to observe the response to a deployed stent, the flow conditions within the original design are not representative of the physiologic conditions in a native vessel. This aspect of the original system presented a need for development in order to be considered by researchers as an accurate in vitro representation of the target vessels in which the stents are used. One of the primary concerns of this environment is creating and maintaining physiologic flow conditions that will represent those present in native vessels in order to facilitate cells sodded on the construct to grow as they would under native conditions. The two key aspects of flow are pulsatility and wall shear stress.Studies in this thesis were carried out to determine the best and most feasible methods for implementing appropriate levels of pulsation and wall shear stress in the previously established BVM bioreactor system with the intention of maintaining the original system's simplicity and high throughput potential. Pulsatile flow was created by elevating backpressure in the BVM chamber while using a different pump head and pump tubing. Wall shear stress was adjusted by altering the viscosity of the perfusate and flow rate through the system. Both pulsatile flow and shear stress were est...

show abstract

Human In Vitro Model Mimicking Material‐Driven Vascular Regeneration Reveals How Cyclic Stretch and Shear Stress Differentially Modulate Inflammation and Matrix Deposition

et al. 2020

View full text Add to dashboard Cite

Resorbable synthetic scaffolds designed to regenerate living tissues and organs inside the body have emerged as a clinically attractive technology to replace diseased blood vessels. However, mismatches between scaffold design and in vivo hemodynamic loading (i.e., cyclic stretch and shear stress) can result in aberrant inflammation and adverse tissue remodeling, leading to premature graft failure. Yet, the underlying mechanisms remain elusive. Here, a human in vitro model is presented that mimics the transient local inflammatory and biomechanical environments that drive scaffold‐guided tissue regeneration. The model is based on the coculture of human (myo)fibroblasts and macrophages in a bioreactor platform that decouples cyclic stretch and shear stress. Using a resorbable supramolecular elastomer as the scaffold material, it is revealed that cyclic stretch initially reduces proinflammatory cytokine secretion and, especially when combined with shear stress, stimulates IL‐10 secretion. Moreover, cyclic stretch stimulates downstream (myo)fibroblast proliferation and matrix deposition. In turn, shear stress attenuates cyclic‐stretch‐induced matrix growth by enhancing MMP‐1/TIMP‐1‐mediated collagen remodeling, and synergistically alters (myo)fibroblast phenotype when combined with cyclic stretch. The findings suggest that shear stress acts as a stabilizing factor in cyclic stretch‐induced tissue formation and highlight the distinct roles of hemodynamic loads in the design of resorbable vascular grafts.

show abstract

Fluid Shear Stress-Induced Alignment of Cultured Vascular Smooth Muscle Cells

Cited by 103 publications

References 39 publications

Extracting Cell and Fibre Orientation from Microscopic Images:Computational Methods and Tools

Extracting Cell and Fibre Orientation from Microscopic Images:Computational Methods and Tools

Implementation of Physiologic Flow Conditions in a Blood Vessel Mimic Bioreactor System for the Evaluation of Intravascular Devices

Human In Vitro Model Mimicking Material‐Driven Vascular Regeneration Reveals How Cyclic Stretch and Shear Stress Differentially Modulate Inflammation and Matrix Deposition

Contact Info

Product

Resources

About