1
|
Lima I, Silva A, Sousa F, Ferreira W, Freire R, de Oliveira C, de Sousa J. Measuring the viscoelastic relaxation function of cells with a time-dependent interpretation of the Hertz-Sneddon indentation model. Heliyon 2024; 10:e30623. [PMID: 38770291 PMCID: PMC11103437 DOI: 10.1016/j.heliyon.2024.e30623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 04/15/2024] [Accepted: 04/30/2024] [Indexed: 05/22/2024] Open
Abstract
The Hertz-Sneddon elastic indentation model is widely adopted in the biomechanical investigation of living cells and other soft materials using atomic force microscopy despite the explicit viscoelastic nature of these materials. In this work, we demonstrate that an exact analytical viscoelastic force model for power-law materials, can be interpreted as a time-dependent Hertz-Sneddon-like model. Characterizing fibroblasts (L929) and osteoblasts (OFCOLII) demonstrates the model's accuracy. Our results show that the difference between Young's modulus E Y obtained by fitting force curves with the Hertz-Sneddon model and the effective Young's modulus derived from the viscoelastic force model is less than 3%, even when cells are probed at large forces where nonlinear deformation effects become significant. We also propose a measurement protocol that involves probing samples at different indentation speeds and forces, enabling the construction of the average viscoelastic relaxation function of samples by conveniently fitting the force curves with the Hertz-Sneddon model.
Collapse
Affiliation(s)
- I.V.M. Lima
- Departamento de Física, Universidade Federal do Ceará, Fortaleza, 60440-900, Ceará, Brazil
| | - A.V.S. Silva
- Departamento de Física, Universidade Federal do Ceará, Fortaleza, 60440-900, Ceará, Brazil
- Instituto Federal do Rio Grande do Norte, Pau dos Ferros, 59900-000, Rio Grande do Norte, Brazil
| | - F.D. Sousa
- Núcleo de Biologia Experimental, Universidade de Fortaleza, Fortaleza, 60811-905, Ceará, Brazil
| | - W.P. Ferreira
- Departamento de Física, Universidade Federal do Ceará, Fortaleza, 60440-900, Ceará, Brazil
| | - R.S. Freire
- Central Analítica, Universidade Federal do Ceará, Fortaleza, 60440-900, Ceará, Brazil
| | - C.L.N. de Oliveira
- Departamento de Física, Universidade Federal do Ceará, Fortaleza, 60440-900, Ceará, Brazil
| | - J.S. de Sousa
- Departamento de Física, Universidade Federal do Ceará, Fortaleza, 60440-900, Ceará, Brazil
| |
Collapse
|
2
|
Wong CA, Fraticelli Guzmán NS, Read AT, Hedberg-Buenz A, Anderson MG, Feola AJ, Sulchek T, Ethier CR. A method for analyzing AFM force mapping data obtained from soft tissue cryosections. J Biomech 2024; 168:112113. [PMID: 38648717 PMCID: PMC11128031 DOI: 10.1016/j.jbiomech.2024.112113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 02/23/2024] [Accepted: 04/17/2024] [Indexed: 04/25/2024]
Abstract
Atomic force microscopy (AFM) is a valuable tool for assessing mechanical properties of biological samples, but interpretations of measurements on whole tissues can be difficult due to the tissue's highly heterogeneous nature. To overcome such difficulties and obtain more robust estimates of tissue mechanical properties, we describe an AFM force mapping and data analysis pipeline to characterize the mechanical properties of cryosectioned soft tissues. We assessed this approach on mouse optic nerve head and rat trabecular meshwork, cornea, and sclera. Our data show that the use of repeated measurements, outlier exclusion, and log-normal data transformation increases confidence in AFM mechanical measurements, and we propose that this methodology can be broadly applied to measuring soft tissue properties from cryosections.
Collapse
Affiliation(s)
- Cydney A Wong
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | | | - A Thomas Read
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Adam Hedberg-Buenz
- Department of Molecular Physiology & Biophysics, University of Iowa, Iowa City, IA
| | - Michael G Anderson
- Department of Molecular Physiology & Biophysics, University of Iowa, Iowa City, IA
| | - Andrew J Feola
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA; Department of Ophthalmology, Emory University, Atlanta, GA; Center for Visual & Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
| | - Todd Sulchek
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA; Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - C Ross Ethier
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA; Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Department of Ophthalmology, Emory University, Atlanta, GA.
| |
Collapse
|
3
|
Wong CA, Fraticelli Guzmán NS, Read AT, Hedberg-Buenz A, Anderson MG, Feola AJ, Sulchek T, Ethier CR. A Method for Analyzing AFM Force Mapping Data Obtained from Soft Tissue Cryosections. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.08.566263. [PMID: 38014311 PMCID: PMC10680563 DOI: 10.1101/2023.11.08.566263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Atomic force microscopy (AFM) is a valuable tool for assessing mechanical properties of biological samples, but interpretations of measurements on whole tissues can be difficult due to the tissue's highly heterogeneous nature. To overcome such difficulties and obtain more robust estimates of tissue mechanical properties, we describe an AFM force mapping and data analysis pipeline to characterize the mechanical properties of cryosectioned soft tissues. We assessed this approach on mouse optic nerve head and rat trabecular meshwork, cornea, and sclera. Our data show that the use of repeated measurements, outlier exclusion, and log-normal data transformation increases confidence in AFM mechanical measurements, and we propose that this methodology can be broadly applied to measuring soft tissue properties from cryosections.
Collapse
Affiliation(s)
- Cydney A Wong
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | | | - A Thomas Read
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
| | - Adam Hedberg-Buenz
- Department of Molecular Physiology & Biophysics, University of Iowa, Iowa City, IA
| | - Michael G Anderson
- Department of Molecular Physiology & Biophysics, University of Iowa, Iowa City, IA
| | - Andrew J Feola
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Ophthalmology, Emory University, Atlanta, GA
- Center for Visual & Neurocognitive Rehabilitation, Atlanta VA Medical Center, Atlanta GA
| | - Todd Sulchek
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - C Ross Ethier
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- Department of Ophthalmology, Emory University, Atlanta, GA
| |
Collapse
|
4
|
Najera J, Rosenberger MR, Datta M. Atomic Force Microscopy Methods to Measure Tumor Mechanical Properties. Cancers (Basel) 2023; 15:3285. [PMID: 37444394 DOI: 10.3390/cancers15133285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/17/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
Atomic force microscopy (AFM) is a popular tool for evaluating the mechanical properties of biological materials (cells and tissues) at high resolution. This technique has become particularly attractive to cancer researchers seeking to bridge the gap between mechanobiology and cancer initiation, progression, and treatment resistance. The majority of AFM studies thus far have been extensively focused on the nanomechanical characterization of cells. However, these approaches fail to capture the complex and heterogeneous nature of a tumor and its host organ. Over the past decade, efforts have been made to characterize the mechanical properties of tumors and tumor-bearing tissues using AFM. This has led to novel insights regarding cancer mechanopathology at the tissue scale. In this Review, we first explain the principles of AFM nanoindentation for the general study of tissue mechanics. We next discuss key considerations when using this technique and preparing tissue samples for analysis. We then examine AFM application in characterizing the mechanical properties of cancer tissues. Finally, we provide an outlook on AFM in the field of cancer mechanobiology and its application in the clinic.
Collapse
Affiliation(s)
- Julian Najera
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Matthew R Rosenberger
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Meenal Datta
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| |
Collapse
|
5
|
Xin Y, Kang BS, Zheng YP, Shan SW, Kee CS, Tan Y. Biophysical properties of corneal cells reflect high myopia progression. Biophys J 2021; 120:3498-3507. [PMID: 34022236 DOI: 10.1016/j.bpj.2021.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 04/07/2021] [Accepted: 05/17/2021] [Indexed: 01/07/2023] Open
Abstract
Myopia is a common ocular disorder with significant alterations in the anterior ocular structure, including the cornea. The cell biophysical phenotype has been proposed to reflect the state of various diseases. However, the biophysical properties of corneal cells have not been characterized during myopia progression and their relationship with myopia remains unknown. This study characterizes the biophysical properties of corneal cells in normal, myopic, and recovered conditions, using two classical myopia models. Surprisingly, myopic corneal cells considerably reduce F-actin and microtubule content and cellular stiffness and generate elevated traction force compared with control cells. When myopia is restored to the healthy state, these biophysical properties are partially or fully restored to the levels of control cells. Furthermore, the level of chromatin condensation is significantly increased in the nucleus of myopic corneal cells and reduced to a level similar to healthy cells after recovery. These findings demonstrate that the reversible biophysical alterations of corneal cells reflect myopia progression, facilitating the study of the role of corneal cell biophysics in myopia.
Collapse
Affiliation(s)
- Ying Xin
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China; Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Byung Soo Kang
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Yong-Ping Zheng
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Sze Wan Shan
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Chea-Su Kee
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China.
| | - Youhua Tan
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China; Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
| |
Collapse
|
6
|
Lee JJ, Rao S, Kaushik G, Azeloglu EU, Costa KD. Dehomogenized Elastic Properties of Heterogeneous Layered Materials in AFM Indentation Experiments. Biophys J 2019; 114:2717-2731. [PMID: 29874620 DOI: 10.1016/j.bpj.2018.04.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 03/16/2018] [Accepted: 04/11/2018] [Indexed: 10/14/2022] Open
Abstract
Atomic force microscopy (AFM) is used to study mechanical properties of biological materials at submicron length scales. However, such samples are often structurally heterogeneous even at the local level, with different regions having distinct mechanical properties. Physical or chemical disruption can isolate individual structural elements but may alter the properties being measured. Therefore, to determine the micromechanical properties of intact heterogeneous multilayered samples indented by AFM, we propose the Hybrid Eshelby Decomposition (HED) analysis, which combines a modified homogenization theory and finite element modeling to extract layer-specific elastic moduli of composite structures from single indentations, utilizing knowledge of the component distribution to achieve solution uniqueness. Using finite element model-simulated indentation of layered samples with micron-scale thickness dimensions, biologically relevant elastic properties for incompressible soft tissues, and layer-specific heterogeneity of an order of magnitude or less, HED analysis recovered the prescribed modulus values typically within 10% error. Experimental validation using bilayer spin-coated polydimethylsiloxane samples also yielded self-consistent layer-specific modulus values whether arranged as stiff layer on soft substrate or soft layer on stiff substrate. We further examined a biophysical application by characterizing layer-specific microelastic properties of full-thickness mouse aortic wall tissue, demonstrating that the HED-extracted modulus of the tunica media was more than fivefold stiffer than the intima and not significantly different from direct indentation of exposed media tissue. Our results show that the elastic properties of surface and subsurface layers of microscale synthetic and biological samples can be simultaneously extracted from the composite material response to AFM indentation. HED analysis offers a robust approach to studying regional micromechanics of heterogeneous multilayered samples without destructively separating individual components before testing.
Collapse
Affiliation(s)
- Jia-Jye Lee
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Biomedical Engineering, The City College of New York, New York, New York
| | - Satish Rao
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Gaurav Kaushik
- Department of Bioengineering, University of California, San Diego, La Jolla, California
| | - Evren U Azeloglu
- Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Kevin D Costa
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, New York.
| |
Collapse
|
7
|
Park K, Lonsberry GE, Gearing M, Levey AI, Desai JP. Viscoelastic Properties of Human Autopsy Brain Tissues as Biomarkers for Alzheimer's Diseases. IEEE Trans Biomed Eng 2019; 66:1705-1713. [PMID: 30371351 PMCID: PMC6605047 DOI: 10.1109/tbme.2018.2878555] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE The present study investigates viscoelastic properties of human autopsy brain tissue via nanoindentation to find feasible biomarkers for Alzheimer's disease (AD) in ex vivo condition and to understand the mechanics of the human brain better, especially on the difference before and after progression of AD. METHODS Viscoelastic properties of paraformaldehyde-fixed, paraffin-embedded thin (8 [Formula: see text]) sectioned normal and AD affected human autopsy brain tissue samples are investigated via nanoindentation with a combined loading profile of a linear preloading and a sinusoidal loading at various loading frequencies from 0.01 to 10 [Formula: see text]. In 1200 indentation tests for ten human autopsy brain tissue samples from ten different subjects (five AD cases and five normal controls), viscoelastic properties such as Young's modulus, storage modulus, loss modulus, and loss factor of both gray and white matter brain tissues samples from normal and AD affected tissues were measured experimentally. RESULTS We found that the normal brain tissues have higher Young's modulus values than the AD affected brain tissues by 23.5 % and 27.9 % on average for gray and white matter, respectively, with statistically significant differences ( ) between the normal and AD affected brain tissues. Additionally, the AD affected brain tissues have much higher loss factor than the normal brain tissues on lower loading frequencies. SIGNIFICANCE AD is one of the leading causes of death in America and continues to affect a growing population. The challenges of recognizing the early pathological changes in brain tissue due to AD and diagnosing a patient has led to much research focused on finding biomarkers for the disease. In this regard, understanding the mechanics of brain tissues is increasingly recognized to play an important role in diagnosing brain diseases.
Collapse
Affiliation(s)
- Kihan Park
- Medical Robotics and Automation Laboratory (RoboMed) in the Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of
Technology, Atlanta, GA, USA
| | - Gabrielle E. Lonsberry
- Medical Robotics and Automation Laboratory (RoboMed) in the Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of
Technology, Atlanta, GA, USA
| | - Marla Gearing
- Department of Pathology and Laboratory Medicine, Emory University
School of Medicine, Atlanta, GA, USA
| | - Allan I. Levey
- Department of Neurology, Emory University School of Medicine,
Atlanta, GA, USA
| | - Jaydev P. Desai
- Medical Robotics and Automation Laboratory (RoboMed) in the Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of
Technology, Atlanta, GA, USA
| |
Collapse
|
8
|
An Iterative Method for Estimating Nonlinear Elastic Constants of Tumor in Soft Tissue from Approximate Displacement Measurements. JOURNAL OF HEALTHCARE ENGINEERING 2019; 2019:2374645. [PMID: 30723537 PMCID: PMC6339765 DOI: 10.1155/2019/2374645] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 06/24/2018] [Accepted: 07/12/2018] [Indexed: 11/17/2022]
Abstract
Objectives Various elastography techniques have been proffered based on linear or nonlinear constitutive models with the aim of detecting and classifying pathologies in soft tissues accurately and noninvasively. Biological soft tissues demonstrate behaviors which conform to nonlinear constitutive models, in particular the hyperelastic ones. In this paper, we represent the results of our steps towards implementing ultrasound elastography to extract hyperelastic constants of a tumor inside soft tissue. Methods Hyperelastic parameters of the unknown tissue have been estimated by applying the iterative method founded on the relation between stress, strain, and the parameters of a hyperelastic model after (a) simulating the medium's response to a sinusoidal load and extracting the tissue displacement fields in some instants and (b) estimating the tissue displacement fields from the recorded/simulated ultrasound radio frequency signals and images using the cross correlation-based technique. Results Our results indicate that hyperelastic parameters of an unidentified tissue could be precisely estimated even in the conditions where there is no prior knowledge of the tissue, or the displacement fields have been approximately calculated using the data recorded by a clinical ultrasound system. Conclusions The accurate estimation of nonlinear elastic constants yields to the correct cognizance of pathologies in soft tissues.
Collapse
|
9
|
Efficient Sensitivity Based Reconstruction Technique to Accomplish Breast Hyperelastic Elastography. BIOMED RESEARCH INTERNATIONAL 2019; 2018:3438470. [PMID: 30596087 PMCID: PMC6286741 DOI: 10.1155/2018/3438470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 07/12/2018] [Accepted: 07/17/2018] [Indexed: 11/17/2022]
Abstract
Hyperelastic models have been acknowledged as constitutive equations which reliably model the nonlinear behaviors observed from soft tissues under various loading conditions. Among them, the Mooney-Rivlin, Yeoh, and polynomial models have been proved capable of accurately modeling responses of breast tissues to applied compressions. Hyperelastic elastography technique takes advantage of the disparities between hyperelastic parameters of varied tissues and the change in hyperelastic parameters in pathological processes. The precise reconstruction of hyperelastic parameters of a completely unknown pathology in the breast in a noninvasive and nondestructive way using the ultrasound elastography has been scrutinized in this paper. In the ultrasound elastography, tissue displacement field is extracted from radio frequency signals or images recorded using the ultrasound medical imaging system; hence the exact displacement field might not be obtained. Our results indicate that the parameters estimated by manipulating the iterative sensitivity-matrix based method converge to tissue's real hyperelastic parameters providing appropriate parameters are assigned to the hypothetical hyperelastic and regularization parameters. Iterative methods have therefore been proposed to compute proper hypothetical hyperelastic and regularization parameters. Accurate estimates of hyperelastic parameters of obscure breast pathology have been achieved even from imprecise measurements of displacements induced in the tissue by the ramp excitation.
Collapse
|
10
|
Park K, Chen W, Chekmareva MA, Foran DJ, Desai JP. Electromechanical Coupling Factor of Breast Tissue as a Biomarker for Breast Cancer. IEEE Trans Biomed Eng 2017; 65:96-103. [PMID: 28436838 DOI: 10.1109/tbme.2017.2695103] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
GOAL This research aims to validate a new biomarker of breast cancer by introducing electromechanical coupling factor of breast tissue samples as a possible additional indicator of breast cancer. Since collagen fibril exhibits a structural organization that gives rise to a piezoelectric effect, the difference in collagen density between normal and cancerous tissue can be captured by identifying the corresponding electromechanical coupling factor. METHODS The design of a portable diagnostic tool and a microelectromechanical systems (MEMS)-based biochip, which is integrated with a piezoresistive sensing layer for measuring the reaction force as well as a microheater for temperature control, is introduced. To verify that electromechanical coupling factor can be used as a biomarker for breast cancer, the piezoelectric model for breast tissue is described with preliminary experimental results on five sets of normal and invasive ductal carcinoma (IDC) samples in the 25-45 temperature range. CONCLUSION While the stiffness of breast tissues can be captured as a representative mechanical signature which allows one to discriminate among tissue types especially in the higher strain region, the electromechanical coupling factor shows more distinct differences between the normal and IDC groups over the entire strain region than the mechanical signature. From the two-sample -test, the electromechanical coupling factor under compression shows statistically significant differences ( 0.0039) between the two groups. SIGNIFICANCE The increase in collagen density in breast tissue is an objective and reproducible characteristic of breast cancer. Although characterization of mechanical tissue property has been shown to be useful for differentiating cancerous tissue from normal tissue, using a single parameter may not be sufficient for practical usage due to inherent variation among biological samples. The portable breast cancer diagnostic tool reported in this manuscript shows the feasibility of measuring multiple parameters of breast tissue allowing for practical application.
Collapse
|
11
|
Dror Y, Sorkin R, Brand G, Boubriak O, Urban J, Klein J. The effect of the serum corona on interactions between a single nano-object and a living cell. Sci Rep 2017; 7:45758. [PMID: 28383528 PMCID: PMC5382918 DOI: 10.1038/srep45758] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 03/06/2017] [Indexed: 12/20/2022] Open
Abstract
Nanoparticles (NPs) which enter physiological fluids are rapidly coated by proteins, forming a so-called corona which may strongly modify their interaction with tissues and cells relative to the bare NPs. In this work the interactions between a living cell and a nano-object, and in particular the effect on this of the adsorption of serum proteins, are directly examined by measuring the forces arising as an Atomic Force Microscope tip (diameter 20 nm) - simulating a nano-object - approaches and contacts a cell. We find that the presence of a serum protein corona on the tip strongly modifies the interaction as indicated by pronounced increase in the indentation, hysteresis and work of adhesion compared to a bare tip. Classically one expects an AFM tip interacting with a cell surface to be repelled due to cell elastic distortion, offset by tip-cell adhesion, and indeed such a model fits the bare-tip/cell interaction, in agreement with earlier work. However, the force plots obtained with serum-modified tips are very different, indicating that the cell is much more compliant to the approaching tip. The insights obtained in this work may promote better design of NPs for drug delivery and other nano-medical applications.
Collapse
Affiliation(s)
- Yael Dror
- Materials and Interfaces Department, Weizmann Institute of Science, Rehovot 76100, Israel.,Department of Physical and Theoretical Chemistry, Oxford University, Oxford OX1 3QZ, United Kingdom
| | - Raya Sorkin
- Materials and Interfaces Department, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Guy Brand
- Materials and Interfaces Department, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Olga Boubriak
- University Laboratory of Physiology, Oxford University, Parks Road, Oxford OX1 3PT, United Kingdom
| | - Jill Urban
- University Laboratory of Physiology, Oxford University, Parks Road, Oxford OX1 3PT, United Kingdom
| | - Jacob Klein
- Materials and Interfaces Department, Weizmann Institute of Science, Rehovot 76100, Israel.,Department of Physical and Theoretical Chemistry, Oxford University, Oxford OX1 3QZ, United Kingdom
| |
Collapse
|
12
|
Maver U, Velnar T, Gaberšček M, Planinšek O, Finšgar M. Recent progressive use of atomic force microscopy in biomedical applications. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2016.03.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
13
|
Zhao X, Zhong Y, Ye T, Wang D, Mao B. Discrimination Between Cervical Cancer Cells and Normal Cervical Cells Based on Longitudinal Elasticity Using Atomic Force Microscopy. NANOSCALE RESEARCH LETTERS 2015; 10:482. [PMID: 26666911 PMCID: PMC4678138 DOI: 10.1186/s11671-015-1174-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 11/25/2015] [Indexed: 05/29/2023]
Abstract
The mechanical properties of cells are considered promising biomarkers for the early diagnosis of cancer. Recently, atomic force microscopy (AFM)-based nanoindentation technology has been utilized for the examination of cell cortex mechanics in order to distinguish malignant cells from normal cells. However, few attempts to evaluate the biomechanical properties of cells have focused on the quantification of the non-homogeneous longitudinal elasticity of cellular structures. In the present study, we applied a variation of the method of Carl and Schillers to investigate the differences between longitudinal elasticity of human cervical squamous carcinoma cells (CaSki) and normal cervical epithelial cells (CRL2614) using AFM. The results reveal a three-layer heterogeneous structure in the probing volume of both cell types studied. CaSki cells exhibited a lower whole-cell stiffness and a softer nuclei zone compared to the normal counterpart cells. Moreover, a better differentiated cytoskeleton was found in the inner cytoplasm/nuclei zone of the normal CRL2614 cells, whereas a deeper cytoskeletal distribution was observed in the probing volume of the cancerous counterparts. The sensitive cortical panel of CaSki cells, with a modulus of 0.35~0.47 kPa, was located at 237~225 nm; in normal cells, the elasticity was 1.20~1.32 kPa at 113~128 nm. The present improved method may be validated using the conventional Hertz-Sneddon method, which is widely reported in the literature. In conclusion, our results enable the quantification of the heterogeneous longitudinal elasticity of cancer cells, in particular the correlation with the corresponding depth. Preliminary results indicate that our method may potentially be applied to improve the detection of cancerous cells and provide insights into the pathophysiology of the disease.
Collapse
Affiliation(s)
- Xueqin Zhao
- College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018, People's Republic of China.
| | - Yunxin Zhong
- State Key Laboratory of Physical Chemistry of the Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, People's Republic of China
| | - Ting Ye
- College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018, People's Republic of China
| | - Dajing Wang
- College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, 310018, People's Republic of China
| | - Bingwei Mao
- State Key Laboratory of Physical Chemistry of the Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, People's Republic of China.
| |
Collapse
|
14
|
Kilpatrick JI, Revenko I, Rodriguez BJ. Nanomechanics of Cells and Biomaterials Studied by Atomic Force Microscopy. Adv Healthc Mater 2015. [PMID: 26200464 DOI: 10.1002/adhm.201500229] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The behavior and mechanical properties of cells are strongly dependent on the biochemical and biomechanical properties of their microenvironment. Thus, understanding the mechanical properties of cells, extracellular matrices, and biomaterials is key to understanding cell function and to develop new materials with tailored mechanical properties for tissue engineering and regenerative medicine applications. Atomic force microscopy (AFM) has emerged as an indispensable technique for measuring the mechanical properties of biomaterials and cells with high spatial resolution and force sensitivity within physiologically relevant environments and timescales in the kPa to GPa elastic modulus range. The growing interest in this field of bionanomechanics has been accompanied by an expanding array of models to describe the complexity of indentation of hierarchical biological samples. Furthermore, the integration of AFM with optical microscopy techniques has further opened the door to a wide range of mechanotransduction studies. In recent years, new multidimensional and multiharmonic AFM approaches for mapping mechanical properties have been developed, which allow the rapid determination of, for example, cell elasticity. This Progress Report provides an introduction and practical guide to making AFM-based nanomechanical measurements of cells and surfaces for tissue engineering applications.
Collapse
Affiliation(s)
- Jason I. Kilpatrick
- Conway Institute of Biomolecular and Biomedical Research; University College Dublin; Belfield Dublin 4 Ireland
| | - Irène Revenko
- Asylum Research an Oxford Instruments Company; 6310 Hollister Avenue Santa Barbara CA 93117 USA
| | - Brian J. Rodriguez
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin; Belfield, Dublin 4, Ireland; School of Physics; University College Dublin; Belfield Dublin 4 Ireland
| |
Collapse
|
15
|
Chen W, Brandes Z, Roy R, Chekmareva M, Pandya HJ, Desai JP, Foran DJ. Robot-Guided Atomic Force Microscopy for Mechano-Visual Phenotyping of Cancer Specimens. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2015; 21:1224-1235. [PMID: 26343283 PMCID: PMC4729564 DOI: 10.1017/s1431927615015007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Atomic force microscopy (AFM) and other forms of scanning probe microscopy have been successfully used to assess biomechanical and bioelectrical characteristics of individual cells. When extending such approaches to heterogeneous tissue, there exists the added challenge of traversing the tissue while directing the probe to the exact location of the targeted biological components under study. Such maneuvers are extremely challenging owing to the relatively small field of view, limited availability of reliable visual cues, and lack of context. In this study we designed a system that leverages the visual topology of the serial tissue sections of interest to help guide robotic control of the AFM stage to provide the requisite navigational support. The process begins by mapping the whole-slide image of a stained specimen with a well-matched, consecutive section of unstained section of tissue in a piecewise fashion. The morphological characteristics and localization of any biomarkers in the stained section can be used to position the AFM probe in the unstained tissue at regions of interest where the AFM measurements are acquired. This general approach can be utilized in various forms of microscopy for navigation assistance in tissue specimens.
Collapse
Affiliation(s)
- Wenjin Chen
- Center for Biomedical Imaging & Informatics, Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
- Department of Pathology and Laboratory Medicine, Rutgers Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, One RWJ Place, New Brunswick, NJ 08901, USA
| | - Zachary Brandes
- Department of Mechanical Engineering, Maryland Robotics Center, Institute for Systems Research, University of Maryland, Glenn L. Martin Hall, College Park, MD 20742, USA
| | - Rajarshi Roy
- Department of Mechanical Engineering, Vanderbilt University, Room 409, 2400 Highland Avenue, Nashville, TN 37205, USA
| | - Marina Chekmareva
- Center for Biomedical Imaging & Informatics, Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
| | - Hardik J. Pandya
- Department of Mechanical Engineering, Maryland Robotics Center, Institute for Systems Research, University of Maryland, Glenn L. Martin Hall, College Park, MD 20742, USA
| | - Jaydev P. Desai
- Department of Mechanical Engineering, Maryland Robotics Center, Institute for Systems Research, University of Maryland, Glenn L. Martin Hall, College Park, MD 20742, USA
| | - David J. Foran
- Center for Biomedical Imaging & Informatics, Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA
- Department of Pathology and Laboratory Medicine, Rutgers Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, One RWJ Place, New Brunswick, NJ 08901, USA
| |
Collapse
|