1
|
Xu H, Zhang J, Zhou Y, Zhao G, Cai M, Gao J, Shao L, Shi Y, Li H, Ji H, Zhao Y, Wang H. Mechanistic Insights into Membrane Protein Clustering Revealed by Visualizing EGFR Secretion. Research (Wash D C) 2022; 2022:9835035. [PMID: 36340505 PMCID: PMC9620640 DOI: 10.34133/2022/9835035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 09/22/2022] [Indexed: 11/19/2022] Open
Abstract
Most plasmalemmal proteins are organized into clusters to modulate various cellular functions. However, the machineries that regulate protein clustering remain largely unclear. Here, with EGFR as an example, we directly and in detail visualized the entire process of EGFR from synthesis to secretion onto the plasma membrane (PM) using a high-speed, high-resolution spinning-disk confocal microscope. First, colocalization imaging revealed that EGFR secretory vesicles underwent transport from the ER to the Golgi to the PM, eventually forming different distribution forms on the apical and basal membranes; that is, most EGFR formed larger clusters on the apical membrane than the basal membrane. A dynamic tracking image and further siRNA interference experiment confirmed that fusion of secretory vesicles with the plasma membrane led to EGFR clusters, and we showed that EGFR PM clustering may be intimately related to EGFR signaling and cell proliferation. Finally, we found that the size and origin of the secretory vesicles themselves may determine the difference in the distribution patterns of EGFR on the PM. More importantly, we showed that actin influenced the EGFR distribution by controlling the fusion of secretory vesicles with the PM. Collectively, a comprehensive understanding of the EGFR secretion process helps us to unravel the EGFR clustering process and elucidate the key factors determining the differences in the spatial distribution of EGFR PM, highlighting the correlation between EGFR secretion and its PM distribution pattern.
Collapse
Affiliation(s)
- Haijiao Xu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
| | - Jinrui Zhang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
| | - Yijia Zhou
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 200031, China
| | - Guanfang Zhao
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
- University of Science and Technology of China, Hefei, 230026 Anhui, China
| | - Mingjun Cai
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
| | - Jing Gao
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
| | - Lina Shao
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
| | - Yan Shi
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
| | - Hongru Li
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
- University of Science and Technology of China, Hefei, 230026 Anhui, China
| | - Hongbin Ji
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 130102, China
| | - Yikai Zhao
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 Jilin, China
- University of Science and Technology of China, Hefei, 230026 Anhui, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 Shandong, China
| |
Collapse
|
2
|
Wu D, Hou Y, Chu Z, Wei Q, Hong W, Lin Y. Ligand Mobility-Mediated Cell Adhesion and Spreading. ACS APPLIED MATERIALS & INTERFACES 2022; 14:12976-12983. [PMID: 35282676 DOI: 10.1021/acsami.1c22603] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cells live in a highly dynamic environment where their physical connection and communication with the outside are achieved through receptor-ligands binding. Therefore, a precise knowledge of the interaction between receptors and ligands is critical for our understanding of how cells execute different biological duties. Interestingly, recent evidence has shown that the mobility of ligands at the cell-extracellular matrix (ECM) interface significantly affects the adhesion and spreading of cells, while the underlying mechanism remains unclear. Here, we present a modeling investigation to address this critical issue. Specifically, by adopting the Langevin dynamics, the random movement of ligands was captured by assigning a stochastic force along with a viscous drag on them. After that, the evolution of adhesion and subsequent spreading of cells were analyzed by considering the force-regulated binding/breakage of individual molecular bonds connecting polymerizing actin bundles inside the cell to the ECM. Interestingly, a biphasic relationship between adhesion and ligand diffusivity was predicted, resulting in maximized cell spreading at intermediate mobility of ligand molecules. In addition, this peak position was found to be dictated by the aggregation of ligands, effectively reducing their diffusivity, and how fast bond association/dissociation can occur. These predictions are in excellent agreement with our experimental observations where distinct ligand mobility was introduced by tuning the interactions between the self-assembly polymer coating and the surface.
Collapse
Affiliation(s)
- Di Wu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 000000, China
- Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Yong Hou
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong 000000, China
| | - Zhiqin Chu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong 000000, China
| | - Qiang Wei
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials and Engineering, Sichuan University, Chengdu 610065, China
| | - Wei Hong
- Department of Mechanics and Aerospace Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Yuan Lin
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 000000, China
- HKU-Shenzhen Institute of Research and Innovation (HKU-SIRI), Shenzhen, Guangdong 518057, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong 000000, China
| |
Collapse
|
3
|
Mierke CT. Viscoelasticity, Like Forces, Plays a Role in Mechanotransduction. Front Cell Dev Biol 2022; 10:789841. [PMID: 35223831 PMCID: PMC8864183 DOI: 10.3389/fcell.2022.789841] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/11/2022] [Indexed: 12/13/2022] Open
Abstract
Viscoelasticity and its alteration in time and space has turned out to act as a key element in fundamental biological processes in living systems, such as morphogenesis and motility. Based on experimental and theoretical findings it can be proposed that viscoelasticity of cells, spheroids and tissues seems to be a collective characteristic that demands macromolecular, intracellular component and intercellular interactions. A major challenge is to couple the alterations in the macroscopic structural or material characteristics of cells, spheroids and tissues, such as cell and tissue phase transitions, to the microscopic interferences of their elements. Therefore, the biophysical technologies need to be improved, advanced and connected to classical biological assays. In this review, the viscoelastic nature of cytoskeletal, extracellular and cellular networks is presented and discussed. Viscoelasticity is conceptualized as a major contributor to cell migration and invasion and it is discussed whether it can serve as a biomarker for the cells' migratory capacity in several biological contexts. It can be hypothesized that the statistical mechanics of intra- and extracellular networks may be applied in the future as a powerful tool to explore quantitatively the biomechanical foundation of viscoelasticity over a broad range of time and length scales. Finally, the importance of the cellular viscoelasticity is illustrated in identifying and characterizing multiple disorders, such as cancer, tissue injuries, acute or chronic inflammations or fibrotic diseases.
Collapse
Affiliation(s)
- Claudia Tanja Mierke
- Faculty of Physics and Earth Science, Peter Debye Institute of Soft Matter Physics, Biological Physics Division, University of Leipzig, Leipzig, Germany
| |
Collapse
|
4
|
Gentile F. Time dependent adhesion of cells on nanorough surfaces. J Biomech 2021; 129:110814. [PMID: 34688065 DOI: 10.1016/j.jbiomech.2021.110814] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 10/07/2021] [Accepted: 10/08/2021] [Indexed: 11/30/2022]
Abstract
Understanding and controlling the mechanisms of cell adhesion to nanomaterials is essential in tissue engineering, regenerative medicine, the development of experimental models for the study of neurodegenerative diseases. Nonetheless, despite the great many of studies that have examined how cells interact with nanoscale surfaces, little is known about the temporal dimension of the process of adhesion. In a previous work, Decuzzi and Ferrari, by examining how the energy of a cell changes while binding to a nanoscale surface, determined a criterion to decide whether nanoroughness can either enhance or retard cell adhesion. While accurate, however their model template disregards the time variable. Here, starting from the work of Decuzzi and Ferrari, we have developed a mathematical model based on chemotaxis that describes how cells adhere to a nanorough surface over time. Relaxing the originating constraint of a fixed density of ligand molecules expressed by the cell membrane, we show that the strength of adhesion depends on time and that, for certain values of the model parameters, a cell can arrive to establish a stable adhesion to a substrate even if the process of binding is initially energetically unfavourable. We show that, for a cell-membrane stiffness of 10kPa, an initial density of receptors of 500bonds/μm2, a specific and non-specific energy density of adhesion of 10-5J/m2 and 10-7J/m2, and roughness in the low nanometer range, cell adhesion forces can be completely activated from few seconds to some tens of minutes from the initial contact with the surface.
Collapse
Affiliation(s)
- F Gentile
- Nanotechnology Research Center, Department of Experimental and Clinical Medicine, University of "Magna Graecia", Catanzaro 88100, Italy.
| |
Collapse
|
5
|
Tang LJW, Zaseela A, Toh CCM, Adine C, Aydar AO, Iyer NG, Fong ELS. Engineering stromal heterogeneity in cancer. Adv Drug Deliv Rev 2021; 175:113817. [PMID: 34087326 DOI: 10.1016/j.addr.2021.05.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/19/2021] [Accepted: 05/29/2021] [Indexed: 02/09/2023]
Abstract
Based on our exponentially increasing knowledge of stromal heterogeneity from advances in single-cell technologies, the notion that stromal cell types exist as a spectrum of unique subpopulations that have specific functions and spatial distributions in the tumor microenvironment has significant impact on tumor modeling for drug development and personalized drug testing. In this Review, we discuss the importance of incorporating stromal heterogeneity and tumor architecture, and propose an overall approach to guide the reconstruction of stromal heterogeneity in vitro for tumor modeling. These next-generation tumor models may support the development of more precise drugs targeting specific stromal cell subpopulations, as well as enable improved recapitulation of patient tumors in vitro for personalized drug testing.
Collapse
Affiliation(s)
- Leon Jia Wei Tang
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Ayshath Zaseela
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | | | - Christabella Adine
- Department of Biomedical Engineering, National University of Singapore, Singapore; The N.1 Institute for Health, National University of Singapore, Singapore
| | - Abdullah Omer Aydar
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - N Gopalakrishna Iyer
- National Cancer Centre Singapore, Singapore; Duke-NUS Medical School, Singapore.
| | - Eliza Li Shan Fong
- Department of Biomedical Engineering, National University of Singapore, Singapore; The N.1 Institute for Health, National University of Singapore, Singapore.
| |
Collapse
|
6
|
Karagöz Z, Geuens T, LaPointe VLS, van Griensven M, Carlier A. Win, Lose, or Tie: Mathematical Modeling of Ligand Competition at the Cell-Extracellular Matrix Interface. Front Bioeng Biotechnol 2021; 9:657244. [PMID: 33996781 PMCID: PMC8117103 DOI: 10.3389/fbioe.2021.657244] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 04/07/2021] [Indexed: 12/19/2022] Open
Abstract
Integrin transmembrane proteins conduct mechanotransduction at the cell–extracellular matrix (ECM) interface. This process is central to cellular homeostasis and therefore is particularly important when designing instructive biomaterials and organoid culture systems. Previous studies suggest that fine-tuning the ECM composition and mechanical properties can improve organoid development. Toward the bigger goal of fully functional organoid development, we hypothesize that resolving the dynamics of ECM–integrin interactions will be highly instructive. To this end, we developed a mathematical model that enabled us to simulate three main interactions, namely integrin activation, ligand binding, and integrin clustering. Different from previously published computational models, we account for the binding of more than one type of ligand to the integrin. This competition between ligands defines the fate of the system. We have demonstrated that an increase in the initial concentration of ligands does not ensure an increase in the steady state concentration of ligand-bound integrins. The ligand with higher binding rate occupies more integrins at the steady state than does the competing ligand. With cell type specific, quantitative input on integrin-ligand binding rates, this model can be used to develop instructive cell culture systems.
Collapse
Affiliation(s)
- Zeynep Karagöz
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, Netherlands
| | - Thomas Geuens
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, Netherlands
| | - Vanessa L S LaPointe
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, Netherlands
| | - Martijn van Griensven
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, Netherlands
| | - Aurélie Carlier
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, Netherlands
| |
Collapse
|
7
|
Taskin MB, Ahmad T, Wistlich L, Meinel L, Schmitz M, Rossi A, Groll J. Bioactive Electrospun Fibers: Fabrication Strategies and a Critical Review of Surface-Sensitive Characterization and Quantification. Chem Rev 2021; 121:11194-11237. [DOI: 10.1021/acs.chemrev.0c00816] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Mehmet Berat Taskin
- Department of Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, 97070 Würzburg, Germany
| | - Taufiq Ahmad
- Department of Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, 97070 Würzburg, Germany
| | - Laura Wistlich
- Department of Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, 97070 Würzburg, Germany
| | - Lorenz Meinel
- Institute of Pharmacy and Food Chemistry and Helmholtz Institute for RNA Based Infection Research, 97074 Würzburg, Germany
| | - Michael Schmitz
- Department of Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, 97070 Würzburg, Germany
| | - Angela Rossi
- Department of Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, 97070 Würzburg, Germany
| | - Jürgen Groll
- Department of Functional Materials in Medicine and Dentistry and Bavarian Polymer Institute, University of Würzburg, 97070 Würzburg, Germany
| |
Collapse
|
8
|
Effect of TiO 2 Nanotube Pore Diameter on Human Mesenchymal Stem Cells and Human Osteoblasts. NANOMATERIALS 2020; 10:nano10112117. [PMID: 33113757 PMCID: PMC7692029 DOI: 10.3390/nano10112117] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/13/2020] [Accepted: 10/20/2020] [Indexed: 12/18/2022]
Abstract
The pore diameter of uniformly structured nanotubes can significantly change the behaviour of cells. Recent studies demonstrated that the activation of integrins is affected not by only the surface chemistry between the cell-material interfaces, but also by the features of surface nanotopography, including nanotube diameter. While research has been carried out in this area, there has yet to be a single systemic study to date that succinctly compares the response of both human stem cells and osteoblasts to a range of TiO2 nanotube pore diameters using controlled experiments in a single laboratory. In this paper, we investigate the influence of surface nanotopography on cellular behaviour and osseointegrative properties through a systemic study involving human mesenchymal stem cells (hMSCs) and human osteoblasts (HOBs) on TiO2 nanotubes of 20 nm, 50 nm and 100 nm pore diameters using in-vitro assessments. This detailed study demonstrates the interrelationship between cellular behaviour and nanotopography, revealing that a 20 nm nanotube pore diameter is preferred by hMSCs for the induction of osteogenic differentiation, while 50 nm nanotubular structures are favourable by HOBs for osteoblastic maturation.
Collapse
|
9
|
Sharifi F, Atyabi SM, Irani S, Bakhshi H. Bone morphogenic protein-2 immobilization by cold atmospheric plasma to enhance the osteoinductivity of carboxymethyl chitosan-based nanofibers. Carbohydr Polym 2020; 231:115681. [DOI: 10.1016/j.carbpol.2019.115681] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/15/2019] [Accepted: 11/25/2019] [Indexed: 01/29/2023]
|
10
|
Young J, Hua X, Somsel H, Reichart F, Kessler H, Spatz JP. Integrin Subtypes and Nanoscale Ligand Presentation Influence Drug Sensitivity in Cancer Cells. NANO LETTERS 2020; 20:1183-1191. [PMID: 31908168 PMCID: PMC7020138 DOI: 10.1021/acs.nanolett.9b04607] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Cancer cell-matrix interactions have been shown to enhance cancer cell survival via the activation of pro-survival signaling pathways. These pathways are initiated at the site of interaction, i.e., integrins, and thus, their inhibition has been the target of therapeutic strategies. Individual roles for fibronectin-binding integrin subtypes αvβ3 and α5β1 have been shown for various cellular processes; however, a systematic comparison of their function in adhesion-dependent chemoresistance is lacking. Here, we utilize integrin subtype-specific peptidomimetics for αvβ3 and α5β1, both as blocking agents on fibronectin-coated surfaces and as surface-immobilized adhesion sites, in order to parse out their role in breast cancer cell survival. Block copolymer micelle nanolithography is utilized to immobilize peptidomimetics onto highly ordered gold nanoparticle arrays with biologically relevant interparticle spacings (35, 50, or 70 nm), thereby providing a platform for ascertaining the dependence of ligand spacing in chemoprotection. We show that several cellular properties-morphology, focal adhesion formation, and migration-are intricately linked to both the integrin subtype and their nanospacing. Importantly, we show that chemotherapeutic drug sensitivity is highly dependent on both parameters, with smaller ligand spacing generally hindering survival. Furthermore, we identify ligand type-specific patterns of drug sensitivity, with enhanced chemosurvival when cells engage αvβ3 vs α5β1 on fibronectin; however, this is heavily reliant on nanoscale spacing, as the opposite is observed when ligands are spaced at 70 nm. These data imply that even nanoscale alterations in extracellular matrix properties have profound effects on cancer cell survival and can thus inform future therapies and drug testing platforms.
Collapse
Affiliation(s)
- Jennifer
L. Young
- Department
of Cellular Biophysics, Max Planck Institute
for Medical Research, 69120 Heidelberg, Germany
- Department
of Biophysical Chemistry, Heidelberg University, 69120 Heidelberg, Germany
| | - Ximeng Hua
- Department
of Cellular Biophysics, Max Planck Institute
for Medical Research, 69120 Heidelberg, Germany
- Department
of Biophysical Chemistry, Heidelberg University, 69120 Heidelberg, Germany
| | - Heidi Somsel
- Department
of Cellular Biophysics, Max Planck Institute
for Medical Research, 69120 Heidelberg, Germany
- Department
of Biophysical Chemistry, Heidelberg University, 69120 Heidelberg, Germany
| | - Florian Reichart
- Department
of Chemistry, Technical University of Munich, 85748 Garching, Germany
| | - Horst Kessler
- Department
of Chemistry, Technical University of Munich, 85748 Garching, Germany
| | - Joachim P. Spatz
- Department
of Cellular Biophysics, Max Planck Institute
for Medical Research, 69120 Heidelberg, Germany
- Department
of Biophysical Chemistry, Heidelberg University, 69120 Heidelberg, Germany
- E-mail: . Phone: +49 6221 486-420
| |
Collapse
|
11
|
Multivalent Binding of a Ligand-Coated Particle: Role of Shape, Size, and Ligand Heterogeneity. Biophys J 2019; 114:1830-1846. [PMID: 29694862 DOI: 10.1016/j.bpj.2018.03.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 03/05/2018] [Accepted: 03/06/2018] [Indexed: 01/18/2023] Open
Abstract
We utilize a multiscale modeling framework to study the effect of shape, size, and ligand composition on the efficacy of binding of a ligand-coated particle to a substrate functionalized with the target receptors. First, we show how molecular dynamics along with steered molecular dynamics calculations can be used to accurately parameterize the molecular-binding free energy and the effective spring constant for a receptor-ligand pair. We demonstrate this for two ligands that bind to the α5β1-domain of integrin. Next, we show how these effective potentials can be used to build computational models at the meso- and continuum-scales. These models incorporate the molecular nature of the receptor-ligand interactions and yet provide an inexpensive route to study the multivalent interaction of receptors and ligands through the construction of Bell potentials customized to the molecular identities. We quantify the binding efficacy of the ligand-coated-particle in terms of its multivalency, binding free-energy landscape, and the losses in the configurational entropies. We show that 1) the binding avidity for particle sizes less than 350 nm is set by the competition between the enthalpic and entropic contributions, whereas that for sizes above 350 nm is dominated by the enthalpy of binding; 2) anisotropic particles display higher levels of multivalent binding compared to those of spherical particles; and 3) variations in ligand composition can alter binding avidity without altering the average multivalency. The methods and results presented here have wide applications in the rational design of functionalized carriers and also in understanding cell adhesion.
Collapse
|
12
|
Multiscale model of integrin adhesion assembly. PLoS Comput Biol 2019; 15:e1007077. [PMID: 31163027 PMCID: PMC6568411 DOI: 10.1371/journal.pcbi.1007077] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 06/14/2019] [Accepted: 05/08/2019] [Indexed: 01/09/2023] Open
Abstract
The ability of adherent cells to form adhesions is critical to numerous phases of their physiology. The assembly of adhesions is mediated by several types of integrins. These integrins differ in physical properties, including rate of diffusion on the plasma membrane, rapidity of changing conformation from bent to extended, affinity for extracellular matrix ligands, and lifetimes of their ligand-bound states. However, the way in which nanoscale physical properties of integrins ensure proper adhesion assembly remains elusive. We observe experimentally that both β-1 and β-3 integrins localize in nascent adhesions at the cell leading edge. In order to understand how different nanoscale parameters of β-1 and β-3 integrins mediate proper adhesion assembly, we therefore develop a coarse-grained computational model. Results from the model demonstrate that morphology and distribution of nascent adhesions depend on ligand binding affinity and strength of pairwise interactions. Organization of nascent adhesions depends on the relative amounts of integrins with different bond kinetics. Moreover, the model shows that the architecture of an actin filament network does not perturb the total amount of integrin clustering and ligand binding; however, only bundled actin architectures favor adhesion stability and ultimately maturation. Together, our results support the view that cells can finely tune the expression of different integrin types to determine both structural and dynamic properties of adhesions.
Collapse
|
13
|
Chafino JA, Yamanaka K, Mercier F, Rivory P, Balvay S, Hartmann DJ, Chiba A, Fabregue D. The influence of temperature during water-quench rapid heat treatment on the microstructure, mechanical properties and biocompatibility of Ti6Al4V ELI alloy. J Mech Behav Biomed Mater 2019; 96:144-151. [PMID: 31035065 DOI: 10.1016/j.jmbbm.2019.04.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 02/22/2019] [Accepted: 04/11/2019] [Indexed: 10/27/2022]
Abstract
This study investigates the influence of a rapid heat treatment followed by water-quenching on the mechanical properties of Ti6Al4V ELI alloy to improve its strength for use in implants. Prior to the experiment, a dilatometry test was performed to understand the progressive α-to β-phase transformation taking place during heating. The results were then used to carry out heat treatments. Microstructure was analysed using SEM, EBSD, EDX and XRD techniques. Vickers micro-hardness, tensile and high cycle rotating bending tests were used to analyse the influence of the $\alpha'$-phase fraction on the strength of the studied alloy. Results show that this process can provide a Ti6Al4V ELI alloy with a better Yield Strength (YS)/uniform deformation (εu) ratio and improved high cycle fatigue strength than those observed in the current microstructure used in medical implants. Lastly, cytotoxicity tests were performed on two types of human cells, namely MG63 osteoblast-like cells and fibroblasts. The results reveal the non-toxicity of the heat-treated Ti6Al4V ELI alloy.
Collapse
Affiliation(s)
- J A Chafino
- Univ Lyon, INSA-Lyon, MATEIS, UMR CNRS 5510, 20 Avenue Einstein, 69621, Villeurbanne, France.
| | - K Yamanaka
- Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - F Mercier
- Univ Lyon, INSA-Lyon, MATEIS, UMR CNRS 5510, 20 Avenue Einstein, 69621, Villeurbanne, France
| | - P Rivory
- Univ Lyon, Universite Claude Bernard Lyon1, MATEIS, UMR CNRS 5510, 8 avenue Rockefeller, 69373, Lyon, France
| | - S Balvay
- Univ Lyon, Universite Claude Bernard Lyon1, MATEIS, UMR CNRS 5510, 8 avenue Rockefeller, 69373, Lyon, France
| | - D J Hartmann
- Univ Lyon, Universite Claude Bernard Lyon1, MATEIS, UMR CNRS 5510, 8 avenue Rockefeller, 69373, Lyon, France
| | - A Chiba
- Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - D Fabregue
- Univ Lyon, INSA-Lyon, MATEIS, UMR CNRS 5510, 20 Avenue Einstein, 69621, Villeurbanne, France.
| |
Collapse
|
14
|
Kollar J, Morelli A, Chiellini F, Miertus S, Bakos D, Frecer V. Epithelial cell adhesion on films mimicking surface of polymeric scaffolds of artificial urethra compared to molecular modeling of integrin binding. J BIOACT COMPAT POL 2019. [DOI: 10.1177/0883911519843309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In this study, a combined experimental and computational study of long-term human bladder epithelial cell line HBLAK adhesion and proliferation on five different polymeric surfaces, namely hyaluronic acid, amylose, collagen, polyhydroxybutyrate, and polylactic acid, was performed with the goal to understand the nature of the attraction between various surface materials and a simplified model of the cell surface (transmembrane protein integrin). These biodegradable polymers are frequently used as scaffolds for tissue engineering. During formation of the new tissue, the scaffold polymers are gradually replaced by the natural extracellular matrix of the proliferating cells. Cell adhesion and proliferation experiments were carried out employing thin polymer films prepared by solvent casting while for the computational approach three-dimensional molecular models of layers of ordered polymeric fibers were used as quasi-planar nano-sized models of polymeric surface patches. Experimental results indicated a good capability of amylose, polyhydroxybutyrate, and hyaluronic acid polymer films to foster cell adhesion. Proliferation experiment, carried out by incubating cells with the investigated polymer films for 72 h, showed that all the investigated polymers are able to sustain a good proliferation of HBLAK cells almost comparable to plain glass. Computational estimate of molecular mechanic interaction energies between three-dimensional models of polymeric films and the collagen-binding α2 I domain of the cell adhesion receptor integrin α2β1 confirmed elevated affinity to amylose and polyhydroxybutyrate that is related to higher polarity of function groups on the film surface as documented by the maps of molecular electrostatic potential. This combined experimental and modeling approach can contribute to rational design and surface modifications of polymeric material suitable for forming the scaffolds of human urethra that can be effectively colonized by stem cells.
Collapse
Affiliation(s)
- Jakub Kollar
- Department of Physical Chemistry of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Bratislava, Slovakia
| | - Andrea Morelli
- Department of Chemistry and Industrial Chemistry, University of Pisa, UdR INSTM Pisa, Pisa, Italy
| | - Federica Chiellini
- Department of Chemistry and Industrial Chemistry, University of Pisa, UdR INSTM Pisa, Pisa, Italy
| | - Stanislav Miertus
- Department of Biotechnologies, Faculty of Natural Sciences, University of Ss. Cyril and Methodius, Trnava, Slovakia
- International Centre for Applied Science and Sustainable Technology (ICARST), Bratislava, Slovakia
| | - Dusan Bakos
- International Centre for Applied Science and Sustainable Technology (ICARST), Bratislava, Slovakia
- Department of Plastics, Rubber and Fibres, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovakia
| | - Vladimir Frecer
- Department of Physical Chemistry of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Bratislava, Slovakia
- International Centre for Applied Science and Sustainable Technology (ICARST), Bratislava, Slovakia
| |
Collapse
|
15
|
Andasari V, Lü D, Swat M, Feng S, Spill F, Chen L, Luo X, Zaman M, Long M. Computational model of wound healing: EGF secreted by fibroblasts promotes delayed re-epithelialization of epithelial keratinocytes. Integr Biol (Camb) 2018; 10:605-634. [PMID: 30206629 PMCID: PMC6571173 DOI: 10.1039/c8ib00048d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It is widely agreed that keratinocyte migration plays a crucial role in wound re-epithelialization. Defects in this function contribute to wound reoccurrence causing significant clinical problems. Several in vitro studies have shown that the speed of migrating keratinocytes can be regulated by epidermal growth factor (EGF) which affects keratinocyte's integrin expression. The relationship between integrin expression (through cell-matrix adhesion) stimulated by EGF and keratinocyte migration speed is not linear since increased adhesion, due to increased integrin expression, has been experimentally shown to slow down cell migration due to the biphasic dependence of cell speed on adhesion. In our previous work we showed that keratinocytes that were co-cultured with EGF-enhanced fibroblasts formed an asymmetric migration pattern, where, the cumulative distances of keratinocytes migrating toward fibroblasts were smaller than those migrating away from fibroblasts. This asymmetric pattern is thought to be provoked by high EGF concentration secreted by fibroblasts. The EGF stimulates the expression of integrin receptors on the surface of keratinocytes migrating toward fibroblasts via paracrine signaling. In this paper, we present a computational model of keratinocyte migration that is controlled by EGF secreted by fibroblasts using the Cellular Potts Model (CPM). Our computational simulation results confirm the asymmetric pattern observed in experiments. These results provide a deeper insight into our understanding of the complexity of keratinocyte migration in the presence of growth factor gradients and may explain re-epithelialization failure in impaired wound healing.
Collapse
Affiliation(s)
- Vivi Andasari
- Boston University, Department of Biomedical Engineering, 44 Cummington Mall, Boston, MA 02215, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Zhao C, Wang X, Gao L, Jing L, Zhou Q, Chang J. The role of the micro-pattern and nano-topography of hydroxyapatite bioceramics on stimulating osteogenic differentiation of mesenchymal stem cells. Acta Biomater 2018; 73:509-521. [PMID: 29678674 DOI: 10.1016/j.actbio.2018.04.030] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 04/14/2018] [Accepted: 04/16/2018] [Indexed: 02/07/2023]
Abstract
The micro/nano hybrid structure is considered to be a biomaterial characteristic to stimulate osteogenesis by mimicking the three-dimensional structure of the bone matrix. However, the mechanism of the hybrid structure induced osteogenic differentiation of stem cells is still unknown. For elucidating the mechanisms, one of the challenge is to directly fabricate micro/nano hybrid structure on bioceramics because of its brittleness. In this study, hydroxyapatite (HA) bioceramics with the micro/nano hybrid structure were firstly fabricated via a hydrothermal treatment and template method, and the effect of the different surface structures on the expression of integrins, BMP2 signaling pathways and cell-cell communication was investigated. Interestingly, the results suggested that the osteogenic differentiation induced by micro/nano structures was modulated first through activating integrins and then further activating BMP2 signaling pathway and cell-cell communication, while activated BMP2 could in turn activate integrins and Cx43-related cell-cell communication. Furthermore, differences in activation of integrins, BMP2 signaling pathway, and gap junction-mediated cell-cell communication were observed, in which nanorod and micropattern structures activated different integrin subunits, BMP downstream receptors and Cx43. This finding may explain the synergistic effect of the micro/nano hybrid structure on the activation of osteogenic differentiation of BMSCs. Based on our study, we concluded that the different activation mechanisms of micro- and nano-structures led to the synergistic stimulatory effect on integrin activation and osteogenesis, in which not only the direct contact of cells on micro/nano structure played an important role, but also other surface characteristics such as protein adsorption might contribute to the bioactive effect. STATEMENT OF SIGNIFICANCE The micro/nano hybrid structure has been found to have synergistic bioactivity on osteogenesis. However, it is still a challenge to fabricate the hybrid structure directly on the bioceramics, and the role of micro- and nano-structure, in particular the mechanism of the micro/nano-hybrid structure induced stem cell differentiation is still unknown. In this study, we firstly fabricated hydroxyapatite bioceramics with the micro/nano hybrid structure, and then investigated the effect of different surface structure on expression of integrins, BMP2 signaling pathways and cell-cell communication. Interestingly, we found that the osteogenic differentiation induced by structure was modulated first through activating integrins and then further activating BMP2 signaling pathway and cell-cell communication, and activated BMP2 could in turn activate some integrin subunits and Cx43-related cell-cell communication. Furthermore, differences in activation of integrins, BMP2 signaling pathway, and gap junction-mediated cell-cell communication were observed, in which nanorod and micropattern structures activated different integrin subunits, BMP downstream receptors and Cx43. This finding may explain the synergistic effect of the micro/nano hybrid structure on the activation of osteogenic differentiation of BMSCs. Based on our study, we concluded that the different activation mechanisms of micro- and nano-structures led to the synergistic stimulatory effect on integrin activation and osteogenesis, in which not only the direct contact of cells on micro/nano structure played an important role, but also other surface characteristics such as protein adsorption might contribute to the bioactive effect.
Collapse
|
17
|
BMP-2 plasmid DNA-loaded chitosan films – A new strategy for bone engineering. J Craniomaxillofac Surg 2017; 45:2084-2091. [DOI: 10.1016/j.jcms.2017.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 08/22/2017] [Accepted: 10/05/2017] [Indexed: 01/09/2023] Open
|
18
|
Visible and UV-curable chitosan derivatives for immobilization of biomolecules. Int J Biol Macromol 2017; 104:1611-1619. [DOI: 10.1016/j.ijbiomac.2017.04.115] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 03/13/2017] [Accepted: 04/30/2017] [Indexed: 11/20/2022]
|
19
|
Lee K, Yu Y. Janus Nanoparticles for T Cell Activation: Clustering Ligands to Enhance Stimulation. J Mater Chem B 2017; 5:4410-4415. [PMID: 28966791 PMCID: PMC5617359 DOI: 10.1039/c7tb00150a] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The in vitro activation of T cells by synthetic particles is a promising technique for adoptive cancer immunotherapy. While it is known that cell-surface receptors form clusters during T cell activation, the use of clustered ligands on synthetic particles to modulate T cell response is a largely unexplored concept. Building upon our previous finding that T cells respond differently to various micro-sized patterns of ligands, we here investigate the effect of nano-sized ligand clusters on T cell activation. Two-faced Janus nanoparticles were fabricated to display ligands of different functions in spatially segregated clusters on single nanoparticles. Going beyond our earlier qualitative study, here we precisely quantified and controlled the surface density and the total amount of ligands on single nanoparticles. We show that nanoparticles with clustered ligands activate T cells to a greater level than ones uniformly coated with the same number of ligands. The enhanced effect is due to increased local surface density of ligands. The results demonstrate that the spatial arrangement of ligands on particles influences activation response of T cells and may be used as a new strategy to increase T cell stimulation in the presence of insufficient amount of stimuli. This fundamental study also represents an initial step in using nanoscale Janus particles for manipulating immune cell responses.
Collapse
Affiliation(s)
- Kwahun Lee
- Department of Chemistry, Indiana University, Bloomington, IN
| | - Yan Yu
- Department of Chemistry, Indiana University, Bloomington, IN
| |
Collapse
|
20
|
Yu J, Huang J, Jansen JA, Xiong C, Walboomers XF. Mechanochemical mechanism of integrin clustering modulated by nanoscale ligand spacing and rigidity of extracellular substrates. J Mech Behav Biomed Mater 2017; 72:29-37. [PMID: 28448919 DOI: 10.1016/j.jmbbm.2017.04.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 04/11/2017] [Accepted: 04/13/2017] [Indexed: 11/25/2022]
Abstract
Experimental findings indicate that cell function and behavior such as cell growth, division, migration and differentiation, are subtly regulated via integrin-dependent cell adhesion. Cell adhesion is influenced by nanoscale ligand spacing and rigidity of extracellular substrates, as cell adhesion drops greatly when the ligand spacing is larger than ~60nm, and cell adhesion is stronger on stiff than soft substrates. However, how nanoscale ligand spacing and substrate stiffness jointly affect integrin clustering and hence nascent cell adhesion remains to be elucidated. To quantitatively investigate the phenomena and the underlying mechanochemical mechanism of integrin clustering modulated by ligand spacing and substrate stiffness, we introduced Monte Carlo simulations varying the values of ligand spacing and substrate stiffness. Moreover, the effects of integrin number, integrin binding free energy, integrin association free energy, and local ligand spacing were investigated. The simulation results showed that integrin clustering decreased sharply, when ligand spacing was relatively large such as dL>60nm in the current simulations, regardless of substrate rigidities, though with close spacing, the clustering increased with the substrate stiffness. The investigation contributes to the goals of understanding and predicting experimental phenomena, directing and optimizing biomaterial design, and manipulating integrin-dependent cell-substrate adhesion in tissue engineering.
Collapse
Affiliation(s)
- Jing Yu
- Center for BioMed-X Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China; Department of Biomaterials, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jianyong Huang
- Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871, PR China.
| | - John A Jansen
- Department of Biomaterials, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Chunyang Xiong
- Center for BioMed-X Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, PR China; Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871, PR China.
| | - X Frank Walboomers
- Department of Biomaterials, Radboud University Medical Center, Nijmegen, The Netherlands.
| |
Collapse
|
21
|
Valdez J, Cook CD, Ahrens CC, Wang AJ, Brown A, Kumar M, Stockdale L, Rothenberg D, Renggli K, Gordon E, Lauffenburger D, White F, Griffith L. On-demand dissolution of modular, synthetic extracellular matrix reveals local epithelial-stromal communication networks. Biomaterials 2017; 130:90-103. [PMID: 28371736 DOI: 10.1016/j.biomaterials.2017.03.030] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/19/2017] [Accepted: 03/21/2017] [Indexed: 02/06/2023]
Abstract
Methods to parse paracrine epithelial-stromal communication networks are a vital need in drug development, as disruption of these networks underlies diseases ranging from cancer to endometriosis. Here, we describe a modular, synthetic, and dissolvable extracellular matrix (MSD-ECM) hydrogel that fosters functional 3D epithelial-stromal co-culture, and that can be dissolved on-demand to recover cells and paracrine signaling proteins intact for subsequent analysis. Specifically, synthetic polymer hydrogels, modified with cell-interacting adhesion motifs and crosslinked with peptides that include a substrate for cell-mediated proteolytic remodeling, can be rapidly dissolved by an engineered version of the microbial transpeptidase Sortase A (SrtA) if the crosslinking peptide includes a SrtA substrate motif and a soluble second substrate. SrtA-mediated dissolution affected only 1 of 31 cytokines and growth factors assayed, whereas standard protease degradation methods destroyed about half of these same molecules. Using co-encapsulated endometrial epithelial and stromal cells as one model system, we show that the dynamic cytokine and growth factor response of co-cultures to an inflammatory cue is richer and more nuanced when measured from SrtA-dissolved gel microenvironments than from the culture supernate. This system employs accessible, reproducible reagents and facile protocols; hence, has potential as a tool in identifying and validating therapeutic targets in complex diseases.
Collapse
Affiliation(s)
- Jorge Valdez
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Christi D Cook
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Caroline Chopko Ahrens
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alex J Wang
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alexander Brown
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Manu Kumar
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Linda Stockdale
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Daniel Rothenberg
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Kasper Renggli
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Elizabeth Gordon
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Douglas Lauffenburger
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Forest White
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Linda Griffith
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| |
Collapse
|
22
|
Wu RX, Yin Y, He XT, Li X, Chen FM. Engineering a Cell Home for Stem Cell Homing and Accommodation. ACTA ACUST UNITED AC 2017; 1:e1700004. [PMID: 32646164 DOI: 10.1002/adbi.201700004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 02/27/2017] [Indexed: 12/14/2022]
Abstract
Distilling complexity to advance regenerative medicine from laboratory animals to humans, in situ regeneration will continue to evolve using biomaterial strategies to drive endogenous cells within the human body for therapeutic purposes; this approach avoids the need for delivering ex vivo-expanded cellular materials. Ensuring the recruitment of a significant number of reparative cells from an endogenous source to the site of interest is the first step toward achieving success. Subsequently, making the "cell home" cell-friendly by recapitulating the natural extracellular matrix (ECM) in terms of its chemistry, structure, dynamics, and function, and targeting specific aspects of the native stem cell niche (e.g., cell-ECM and cell-cell interactions) to program and steer the fates of those recruited stem cells play equally crucial roles in yielding a therapeutically regenerative solution. This review addresses the key aspects of material-guided cell homing and the engineering of novel biomaterials with desirable ECM composition, surface topography, biochemistry, and mechanical properties that can present both biochemical and physical cues required for in situ tissue regeneration. This growing body of knowledge will likely become a design basis for the development of regenerative biomaterials for, but not limited to, future in situ tissue engineering and regeneration.
Collapse
Affiliation(s)
- Rui-Xin Wu
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Yuan Yin
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Xiao-Tao He
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Xuan Li
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| | - Fa-Ming Chen
- State Key Laboratory of Military Stomatology, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P. R. China.,National Clinical Research Center for Oral Diseases, Department of Periodontology, School of Stomatology, Fourth Military Medical University, Xi'an, P.R. China
| |
Collapse
|
23
|
Vats K, Marsh G, Harding K, Zampetakis I, Waugh RE, Benoit DSW. Nanoscale physicochemical properties of chain- and step-growth polymerized PEG hydrogels affect cell-material interactions. J Biomed Mater Res A 2017; 105:1112-1122. [PMID: 28093865 DOI: 10.1002/jbm.a.36007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 01/06/2017] [Accepted: 01/11/2017] [Indexed: 12/15/2022]
Abstract
Poly(ethylene glycol) (PEG) hydrogels provide a versatile platform to develop cell instructive materials through incorporation of a variety of cell adhesive ligands and degradable chemistries. Synthesis of PEG gels can be accomplished via two mechanisms: chain and step growth polymerizations. The mechanism dramatically impacts hydrogel nanostructure, whereby chain polymerized hydrogels are highly heterogeneous and step growth networks exhibit more uniform structures. Underpinning these alterations in nanostructure of chain polymerized hydrogels are densely-packed hydrophobic poly(methyl methacrylate) or poly(acrylate) kinetic chains between hydrophilic PEG crosslinkers. As cell-material interactions, such as those mediated by integrins, occur at the nanoscale and affect cell behavior, it is important to understand how different modes of polymerization translate into nanoscale mechanical and hydrophobic heterogeneities of hydrogels. Therefore, chain- and step-growth polymerized PEG hydrogels with macroscopically similar macromers and compliance (for example, methacrylate-functionalized PEG (PEGDM), MW = 10 kDa and norbornene-functionalized 4-arm PEG (PEGnorb), MW = 10 kDa) were used to examine potential nanoscale differences in hydrogel mechanics and hydrophobicity using atomic force microscopy (AFM). It was found that chain-growth polymerized network yielded greater heterogeneities in both stiffness and hydrophobicity as compared to step-growth polymerized networks. These nanoscale heterogeneities impact cell-material interactions, particularly human mesenchymal stem cell (hMSC) adhesion and spreading, which has implications in use of these hydrogels for tissue engineering applications. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1112-1122, 2017.
Collapse
Affiliation(s)
- Kanika Vats
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
| | - Graham Marsh
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
| | - Kristen Harding
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
| | - Ioannis Zampetakis
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
| | - Richard E Waugh
- Department of Biomedical Engineering, University of Rochester, Rochester, New York.,Department of Biochemistry and Biophysics, University of Rochester, Rochester, New York.,Department of Pharmacology and Physiology, University of Rochester, Rochester, New York
| | - Danielle S W Benoit
- Department of Biomedical Engineering, University of Rochester, Rochester, New York.,Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York.,Department of Chemical Engineering, University of Rochester, Rochester, New York
| |
Collapse
|
24
|
Pallarola D, Platzman I, Bochen A, Cavalcanti-Adam EA, Axmann M, Kessler H, Geiger B, Spatz JP. Focal adhesion stabilization by enhanced integrin-cRGD binding affinity. ACTA ACUST UNITED AC 2017. [DOI: 10.1515/bnm-2016-0014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
AbstractIn this study we investigate the impact of ligand presentation by various molecular spacers on integrin-based focal adhesion formation. Gold nanoparticles (AuNPs) arranged in hexagonal patterns were biofunctionalized with the same ligand head group, cyclic Arg-Gly-Asp [
Collapse
|
25
|
Karimi F, McKenzie TG, O'Connor AJ, Qiao GG, Heath DE. Nano-scale clustering of integrin-binding ligands regulates endothelial cell adhesion, migration, and endothelialization rate: novel materials for small diameter vascular graft applications. J Mater Chem B 2017; 5:5942-5953. [DOI: 10.1039/c7tb01298e] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Blood contacting devices are commonly used in today's medical landscape.
Collapse
Affiliation(s)
- Fatemeh Karimi
- School of Chemical and Biomedical Engineering
- Particulate Fluids Processing Centre
- University of Melbourne
- Melbourne
- Australia
| | - Thomas G. McKenzie
- Polymer Science Group
- Department of Chemical Engineering
- Particulate Fluids Processing Centre
- University of Melbourne
- Melbourne
| | - Andrea J. O'Connor
- School of Chemical and Biomedical Engineering
- Particulate Fluids Processing Centre
- University of Melbourne
- Melbourne
- Australia
| | - Greg G. Qiao
- Polymer Science Group
- Department of Chemical Engineering
- Particulate Fluids Processing Centre
- University of Melbourne
- Melbourne
| | - Daniel E. Heath
- School of Chemical and Biomedical Engineering
- Particulate Fluids Processing Centre
- University of Melbourne
- Melbourne
- Australia
| |
Collapse
|
26
|
Boyd PS, Struve N, Bach M, Eberle JP, Gote M, Schock F, Cremer C, Kriegs M, Hausmann M. Clustered localization of EGFRvIII in glioblastoma cells as detected by high precision localization microscopy. NANOSCALE 2016; 8:20037-20047. [PMID: 27883139 DOI: 10.1039/c6nr05880a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
For receptor tyrosine kinases supramolecular organization on the cell membrane is critical for their function. Super-resolution fluorescence microscopy techniques have offered new opportunities for the analysis of single receptor localization. Here, we analysed the cluster formation of the epidermal growth factor receptor variant III (EGFRvIII), a deletion variant which is expressed in glioblastoma. The constitutively activated variant EGFRvIII is expressed in cells with an egfr gene amplification and is thought to enhance the tumorigenic potential especially of glioblastoma cells. Due to the lack of an adequate model system, it is still unclear how endogenous EGFRvIII expression alters cellular signalling and if it is organized in clusters like the wild type receptor. We have recently described the establishment of two pairs of iso-genetic cell lines (BS153 and DKMG), displaying endogenous EGFRvIII expression or not. Using these cell lines we investigated single receptor localization of EGFRvIII by high precision localization microscopy. Cluster analysis revealed that EGFRvIII is present in clusters on the surface of the cells, with about 60% or even more receptor molecules being assembled in clusters of approximately 100 nm in diameter whereby the cluster definition was iteratively determined. The signal to signal distance may indicate dimer formation while signal quantification indicates 1 × 106-5 × 106 EGFRvIII molecules per cell. Altogether, these data give unique insights into the membrane surface localization of EGFRvIII in glioblastoma cells. These insights will help to unveil the function of this tumour associated receptor variant which might lead to a better understanding of glioblastoma and therefore could lead to improved therapy approaches.
Collapse
Affiliation(s)
- Philip S Boyd
- Kirchhoff-Institute for Physics, University of Heidelberg, Im Neuenheimer Feld 227, 69120 Heidelberg, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Huang Y, Wang Y, Sun L, Agrawal R, Zhang M. Sundew adhesive: a naturally occurring hydrogel. J R Soc Interface 2016; 12:rsif.2015.0226. [PMID: 25948615 DOI: 10.1098/rsif.2015.0226] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Bioadhesives have drawn increasing interest in recent years, owing to their eco-friendly, biocompatible and biodegradable nature. As a typical bioadhesive, sticky exudate observed on the stalked glands of sundew plants aids in the capture of insects and this viscoelastic adhesive has triggered extensive interests in revealing the implied adhesion mechanisms. Despite the significant progress that has been made, the structural traits of the sundew adhesive, especially the morphological characteristics in nanoscale, which may give rise to the viscous and elastic properties of this mucilage, remain unclear. Here, we show that the sundew adhesive is a naturally occurring hydrogel, consisting of nano-network architectures assembled with polysaccharides. The assembly process of the polysaccharides in this hydrogel is proposed to be driven by electrostatic interactions mediated with divalent cations. Negatively charged nanoparticles, with an average diameter of 231.9 ± 14.8 nm, are also obtained from this hydrogel and these nanoparticles are presumed to exert vital roles in the assembly of the nano-networks. Further characterization via atomic force microscopy indicates that the stretching deformation of the sundew adhesive is associated with the flexibility of its fibrous architectures. It is also observed that the adhesion strength of the sundew adhesive is susceptible to low temperatures. Both elasticity and adhesion strength of the sundew adhesive reduce in response to lowering the ambient temperature. The feasibility of applying sundew adhesive for tissue engineering is subsequently explored in this study. Results show that the fibrous scaffolds obtained from sundew adhesive are capable of increasing the adhesion of multiple types of cells, including fibroblast cells and smooth muscle cells, a property that results from the enhanced adsorption of serum proteins. In addition, in light of the weak cytotoxic activity exhibited by these scaffolds towards a variety of mammal cells, evidence is sufficient to propose that sundew adhesive is a promising nanomaterial worth further exploitation in the field of tissue engineering.
Collapse
Affiliation(s)
- Yujian Huang
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH 43210, USA Dorothy M. Davis Heart and Lung Research Institute, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Yongzhong Wang
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH 43210, USA Dorothy M. Davis Heart and Lung Research Institute, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Leming Sun
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH 43210, USA Dorothy M. Davis Heart and Lung Research Institute, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Richa Agrawal
- Department of Chemistry & Biochemistry, College of Arts and Sciences, The Ohio State University, Columbus, OH 43210, USA
| | - Mingjun Zhang
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH 43210, USA Dorothy M. Davis Heart and Lung Research Institute, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| |
Collapse
|
28
|
Chainoglou E, Karagkiozaki V, Choli-Papadopoulou T, Mavromanolis C, Laskarakis A, Logothetidis S. Development of Biofunctionalized Cellulose Acetate Nanoscaffolds for Heart Valve Tissue Engineering. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/wjnse.2016.64013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
29
|
Benitez PL, Mascharak S, Proctor AC, Heilshorn SC. Use of protein-engineered fabrics to identify design rules for integrin ligand clustering in biomaterials. Integr Biol (Camb) 2015; 8:50-61. [PMID: 26692238 DOI: 10.1039/c5ib00258c] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
While ligand clustering is known to enhance integrin activation, this insight has been difficult to apply to the design of implantable biomaterials because the local and global ligand densities that enable clustering-enhanced integrin signaling were unpredictable. Here, two general design principles for biomaterial ligand clustering are elucidated. First, clustering ligands enhances integrin-dependent signals when the global ligand density, i.e., the ligand density across the cellular length scale, is near the ligand's effective dissociation constant (KD,eff). Second, clustering ligands enhances integrin activation when the local ligand density, i.e., the ligand density across the length scale of individual focal adhesions, is less than an overcrowding threshold. To identify these principles, we fabricated a series of elastin-like, electrospun fabrics with independent control over the local (0 to 122 000 ligands μm(-2)) and global (0 to 71 000 ligand μm(-2)) densities of an arginine-glycine-aspartate (RGD) ligand. Antibody blocking studies confirmed that human umbilical vein endothelial cell adhesion to these protein-engineered biomaterials was primarily due to αVβ3 integrin binding. Clustering ligands enhanced cell proliferation, focal adhesion number, and focal adhesion kinase expression near the ligand's KD,eff of 12 000 RGD μm(-2). Near this global ligand density, cells on ligand-clustered fabrics behaved similarly to cells grown on fabrics with significantly larger global ligand densities but without clustering. However, this enhanced ligand-clustering effect was not observed above a threshold cut-off concentration. At a local ligand density of 122 000 RGD μm(-2), cell division, focal adhesion number, and focal adhesion kinase expression were significantly reduced relative to fabrics with identical global ligand density and lesser local ligand densities. Thus, when clustering results in overcrowding of ligands, integrin receptors are no longer able to effectively engage with their target ligands. Together, these two insights into the cellular responses to ligand clustering at the cell-matrix interface may serve as design principles when developing future generations of implantable biomaterials.
Collapse
Affiliation(s)
- Patrick L Benitez
- Department of Bioengineering, Stanford University, 476 Lomita Mall, Stanford, CA 94305,
| | - Shamik Mascharak
- Department of Bioengineering, Stanford University, 476 Lomita Mall, Stanford, CA 94305,
| | - Amy C Proctor
- Department of Chemical Engineering, Stanford University, 476 Lomita Mall, Stanford, CA 94305,
| | - Sarah C Heilshorn
- Department of Materials Science and Engineering, Stanford University, 476 Lomita Mall, Stanford, CA 94305
| |
Collapse
|
30
|
Haque A, Adnan N, Motazedian A, Akter F, Hossain S, Kutsuzawa K, Nag K, Kobatake E, Akaike T. An Engineered N-Cadherin Substrate for Differentiation, Survival, and Selection of Pluripotent Stem Cell-Derived Neural Progenitors. PLoS One 2015; 10:e0135170. [PMID: 26244942 PMCID: PMC4526632 DOI: 10.1371/journal.pone.0135170] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/18/2015] [Indexed: 11/18/2022] Open
Abstract
For stem cell-based treatment of neurodegenerative diseases a better understanding of key developmental signaling pathways and robust techniques for producing neurons with highest homogeneity are required. In this study, we demonstrate a method using N-cadherin-based biomimetic substrate to promote the differentiation of mouse embryonic stem cell (ESC)- and induced pluripotent stem cell (iPSC)-derived neural progenitor cells (NPCs) without exogenous neuro-inductive signals. We showed that substrate-dependent activation of N-cadherin reduces Rho/ROCK activation and β-catenin expression, leading to the stimulation of neurite outgrowth and conversion into cells expressing neural/glial markers. Besides, plating dissociated cells on N-cadherin substrate can significantly increase the differentiation yield via suppression of dissociation-induced Rho/ROCK-mediated apoptosis. Because undifferentiated ESCs and iPSCs have low affinity to N-cadherin, plating dissociated cells on N-cadherin-coated substrate increase the homogeneity of differentiation by purging ESCs and iPSCs (~30%) from a mixture of undifferentiated cells with NPCs. Using this label-free cell selection approach we enriched differentiated NPCs plated as monolayer without ROCK inhibitor. Therefore, N-cadherin biomimetic substrate provide a powerful tool for basic study of cell—material interaction in a spatially defined and substrate-dependent manner. Collectively, our approach is efficient, robust and cost effective to produce large quantities of differentiated cells with highest homogeneity and applicable to use with other types of cells.
Collapse
Affiliation(s)
- Amranul Haque
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Nihad Adnan
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Ali Motazedian
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Farhima Akter
- Department of Biological Information, Tokyo Institute of Technology, Yokohama, Japan
| | - Sharif Hossain
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Koichi Kutsuzawa
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Kakon Nag
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
| | - Eiry Kobatake
- Department of Biological Information, Tokyo Institute of Technology, Yokohama, Japan
| | - Toshihiro Akaike
- Department of Biomolecular Engineering, Tokyo Institute of Technology, Yokohama, Japan
- * E-mail:
| |
Collapse
|
31
|
Chandra P, Lee SJ. Synthetic Extracellular Microenvironment for Modulating Stem Cell Behaviors. Biomark Insights 2015; 10:105-16. [PMID: 26106260 PMCID: PMC4472032 DOI: 10.4137/bmi.s20057] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 04/12/2015] [Accepted: 04/13/2015] [Indexed: 11/30/2022] Open
Abstract
The innate ability of stem cells to self-renew and differentiate into multiple cell types makes them a promising source for tissue engineering and regenerative medicine applications. Their capacity for self-renewal and differentiation is largely influenced by the combination of physical, chemical, and biological signals found in the stem cell niche, both temporally and spatially. Embryonic and adult stem cells are potentially useful for cell-based approaches; however, regulating stem cell behavior remains a major challenge in their clinical use. Most of the current approaches for controlling stem cell fate do not fully address all of the complex signaling pathways that drive stem cell behaviors in their natural microenvironments. To overcome this limitation, a new generation of biomaterials is being developed for use as three-dimensional synthetic microenvironments that can mimic the regulatory characteristics of natural extracellular matrix (ECM) proteins and ECM-bound growth factors. These synthetic microenvironments are currently being investigated as a substrate with surface immobilization and controlled release of bioactive molecules to direct the stem cell fate in vitro, as a tissue template to guide and improve the neo-tissue formation both in vitro and in vivo, and as a delivery vehicle for cell therapy in vivo. The continued advancement of such an intelligent biomaterial system as the synthetic extracellular microenvironment holds the promise of improved therapies for numerous debilitating medical conditions for which no satisfactory cure exists today.
Collapse
Affiliation(s)
- Prafulla Chandra
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Sang Jin Lee
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| |
Collapse
|
32
|
In PC3 prostate cancer cells ephrin receptors crosstalk to β1-integrins to strengthen adhesion to collagen type I. Sci Rep 2015; 5:8206. [PMID: 25644492 PMCID: PMC4314628 DOI: 10.1038/srep08206] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 01/13/2015] [Indexed: 02/08/2023] Open
Abstract
Eph receptor (Eph) and ephrin signaling can play central roles in prostate cancer and other cancer types. Exposed to ephrin-A1 PC3 prostate cancer cells alter adhesion to extracellular matrix (ECM) proteins. However, whether PC3 cells increase or reduce adhesion, and by which mechanisms they change adhesion to the ECM remains to be characterized. Here, we assay how ephrin-A1 stimulates PC3 cells to adhere to ECM proteins using single-cell force spectroscopy. We find that PC3 cells binding to immobilized ephrin-A1 but not to solubilized ephrin-A1 specifically strengthen adhesion to collagen I. This Eph-ephrin-A1 signaling, which we suppose is based on mechanotransduction, stimulates β1-subunit containing integrin adhesion via the protein kinase Akt and the guanine nucleotide-exchange factor cytohesin. Inhibiting the small GTPases, Rap1 or Rac1, generally lowered adhesion of PC3 prostate cancer cells. Our finding suggests a mechanism by which PC3 prostate cancer cells exposed to ephrins crosstalk to β1-integrins and preferably metastasize in bone, a collagen I rich tissue.
Collapse
|
33
|
Duncan GA, Bevan MA. Colloidal potentials mediated by specific biomolecular interactions. SOFT MATTER 2014; 10:8524-8532. [PMID: 25251902 DOI: 10.1039/c4sm01300j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present a systematic study of receptor-ligand interactions with increasing complexity from interactions in bulk solution, on planar and colloid surfaces, and as part of mediating colloidal pair interactions. We report analytical models that relate receptor-ligand dissociation constants (KD), interactions potentials (U(r)), and adsorbed amounts (θ) for different ligand sizes, concentrations and immobilized receptor coverages. Analytical results are validated for hard core + harmonic well receptor-ligand interactions in bulk and interfacial systems using Monte Carlo (MC) simulations, although any biomolecular interaction can be incorporated into the reported analysis via a "B2 device". Results from analytical models are used to understand potentials of mean force (W(L)) for ligand mediated interactions between receptor decorated colloids. W(L) are generated using MC-umbrella sampling (MC-US) simulations with cluster moves, which provide self-consistent comparisons of net colloid scale interactions with receptor-ligand scale information. Our findings capture how receptor-ligand interactions mediate colloid scale interactions relevant to self-assembly, drug delivery, and biosensing.
Collapse
Affiliation(s)
- Gregg A Duncan
- Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
| | | |
Collapse
|
34
|
Han L, Lin H, Lu X, Zhi W, Wang K, Meng F, Jiang O. BMP2-encapsulated chitosan coatings on functionalized Ti surfaces and their performance in vitro and in vivo. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2014; 40:1-8. [DOI: 10.1016/j.msec.2014.03.043] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 02/17/2014] [Accepted: 03/18/2014] [Indexed: 01/01/2023]
|
35
|
Tung JC, Paige SL, Ratner BD, Murry CE, Giachelli CM. Engineered biomaterials control differentiation and proliferation of human-embryonic-stem-cell-derived cardiomyocytes via timed Notch activation. Stem Cell Reports 2014; 2:271-81. [PMID: 24672751 PMCID: PMC3964284 DOI: 10.1016/j.stemcr.2014.01.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 01/20/2014] [Accepted: 01/23/2014] [Indexed: 12/31/2022] Open
Abstract
For cell-based treatments of myocardial infarction, a better understanding of key developmental signaling pathways and more robust techniques for producing cardiomyocytes are required. Manipulation of Notch signaling has promise as it plays an important role during cardiovascular development, but previous studies presented conflicting results that Notch activation both positively and negatively regulates cardiogenesis. We developed surface- and microparticle-based Notch-signaling biomaterials that function in a time-specific activation-tunable manner, enabling precise investigation of Notch activation at specific developmental stages. Using our technologies, a biphasic effect of Notch activation on cardiac differentiation was found: early activation in undifferentiated human embryonic stem cells (hESCs) promotes ectodermal differentiation, activation in specified cardiovascular progenitor cells increases cardiac differentiation. Signaling also induces cardiomyocyte proliferation, and repeated doses of Notch-signaling microparticles further enhance cardiomyocyte population size. These results highlight the diverse effects of Notch activation during cardiac development and provide approaches for generating large quantities of cardiomyocytes.
Collapse
Affiliation(s)
- Jason C Tung
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Sharon L Paige
- Department of Pathology, University of Washington, Seattle, WA 98195, USA ; Center for Cardiovascular Biology, Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA
| | - Buddy D Ratner
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Charles E Murry
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA ; Department of Pathology, University of Washington, Seattle, WA 98195, USA ; Department of Medicine/Cardiology, University of Washington, Seattle, WA 98195, USA ; Center for Cardiovascular Biology, Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA
| | - Cecilia M Giachelli
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| |
Collapse
|
36
|
Sivan U, Jayakumar K, Krishnan LK. Matrix-directed differentiation of human adipose-derived mesenchymal stem cells to dermal-like fibroblasts that produce extracellular matrix. J Tissue Eng Regen Med 2014; 10:E546-E558. [DOI: 10.1002/term.1865] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 11/02/2013] [Accepted: 12/16/2013] [Indexed: 12/22/2022]
Affiliation(s)
- Unnikrishnan Sivan
- Thrombosis Research Unit, Biomedical Technology Wing; Sree Chitra Tirunal Institute for Medical Sciences and Technology; Thiruvananthapuram Kerala India
| | - K. Jayakumar
- Department of Cardiovascular and Thoracic Surgery; Sree Chitra Tirunal Institute for Medical Sciences and Technology; Thiruvananthapuram Kerala India
| | - Lissy K. Krishnan
- Thrombosis Research Unit, Biomedical Technology Wing; Sree Chitra Tirunal Institute for Medical Sciences and Technology; Thiruvananthapuram Kerala India
| |
Collapse
|
37
|
Meregalli M, Farini A, Sitzia C, Torrente Y. Advancements in stem cells treatment of skeletal muscle wasting. Front Physiol 2014; 5:48. [PMID: 24575052 PMCID: PMC3921573 DOI: 10.3389/fphys.2014.00048] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 01/25/2014] [Indexed: 01/01/2023] Open
Abstract
Muscular dystrophies (MDs) are a heterogeneous group of inherited disorders, in which progressive muscle wasting and weakness is often associated with exhaustion of muscle regeneration potential. Although physiological properties of skeletal muscle tissue are now well known, no treatments are effective for these diseases. Muscle regeneration was attempted by means transplantation of myogenic cells (from myoblast to embryonic stem cells) and also by interfering with the malignant processes that originate in pathological tissues, such as uncontrolled fibrosis and inflammation. Taking into account the advances in the isolation of new subpopulation of stem cells and in the creation of artificial stem cell niches, we discuss how these emerging technologies offer great promises for therapeutic approaches to muscle diseases and muscle wasting associated with aging.
Collapse
Affiliation(s)
- Mirella Meregalli
- Stem Cell Laboratory, Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Centro Dino Ferrari, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano Milano, Italy
| | - Andrea Farini
- Stem Cell Laboratory, Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Centro Dino Ferrari, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano Milano, Italy
| | - Clementina Sitzia
- Stem Cell Laboratory, Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Centro Dino Ferrari, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano Milano, Italy
| | - Yvan Torrente
- Stem Cell Laboratory, Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Centro Dino Ferrari, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano Milano, Italy
| |
Collapse
|
38
|
Rodríguez-Velázquez E, Silva M, Taboada P, Mano JF, Suárez-Quintanilla D, Alatorre-Meda M. Enhanced Cell Affinity of Chitosan Membranes Mediated by Superficial Cross-Linking: A Straightforward Method Attainable by Standard Laboratory Procedures. Biomacromolecules 2013; 15:291-301. [DOI: 10.1021/bm401541v] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
| | | | | | - João F Mano
- 3B’s
Research Group, Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of
the European Institute of Excellence on Tissue Engineering and Regenerative
Medicine, AvePark, Zona Industrial
da Gandra, S. Claudio do Barco, 4806−909 Caldas das Taipas, Guimarães, Portugal
- ICVS/3B’s—PT
Government Associate Laboratory, Braga/Guimarães, Portugal
| | - David Suárez-Quintanilla
- International
Orthodontic Center (IOC), Avenida de
A Coruña 6, E-15706 Santiago de Compostela, Spain
| | - Manuel Alatorre-Meda
- 3B’s
Research Group, Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of
the European Institute of Excellence on Tissue Engineering and Regenerative
Medicine, AvePark, Zona Industrial
da Gandra, S. Claudio do Barco, 4806−909 Caldas das Taipas, Guimarães, Portugal
- ICVS/3B’s—PT
Government Associate Laboratory, Braga/Guimarães, Portugal
| |
Collapse
|
39
|
A spatial model for integrin clustering as a result of feedback between integrin activation and integrin binding. Biophys J 2013; 103:1379-89. [PMID: 22995511 DOI: 10.1016/j.bpj.2012.08.021] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Revised: 07/19/2012] [Accepted: 08/01/2012] [Indexed: 12/16/2022] Open
Abstract
Integrins are transmembrane adhesion receptors that bind extracellular matrix (ECM) proteins and signal bidirectionally to regulate cell adhesion and migration. In many cell types, integrins cluster at cell-ECM contacts to create the foundation for adhesion complexes that transfer force between the cell and the ECM. Even though the temporal and spatial regulation of these integrin clusters is essential for cell migration, how cells regulate their formation is currently unknown. It has been shown that integrin cluster formation is independent of actin stress fiber formation, but requires active (high-affinity) integrins, phosphoinositol-4,5-bisphosphate (PIP2), talin, and immobile ECM ligand. Based on these observations, we propose a minimal model for initial formation of integrin clusters, facilitated by localized activation and binding of integrins to ECM ligands as a result of biochemical feedback between integrin binding and integrin activation. By employing a diffusion-reaction framework for modeling these reactions, we show how spatial organization of bound integrins into clusters may be achieved by a local source of active integrins, namely protein complexes formed on the cytoplasmic tails of bound integrins. Further, we show how such a mechanism can turn small local increases in the concentration of active talin or active integrin into integrin clusters via positive feedback. Our results suggest that the formation of integrin clusters by the proposed mechanism depends on the relationships between production and diffusion of integrin-activating species, and that changes to the relative rates of these processes may affect the resulting properties of integrin clusters.
Collapse
|
40
|
Ivanova VP, Kovaleva ZV, Anokhina VV, Krivchenko AI. The effect of a collagen tripeptide fragment (GER) on fibroblast adhesion and spreading depends on properties of an adhesive surface. ACTA ACUST UNITED AC 2013. [DOI: 10.1134/s1990519x13010057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
41
|
McMahon RE, Wang L, Skoracki R, Mathur AB. Development of nanomaterials for bone repair and regeneration. J Biomed Mater Res B Appl Biomater 2012; 101:387-97. [DOI: 10.1002/jbm.b.32823] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2012] [Revised: 07/31/2012] [Accepted: 08/05/2012] [Indexed: 11/05/2022]
|
42
|
Lo Schiavo V, Robert P, Limozin L, Bongrand P. Quantitative modeling assesses the contribution of bond strengthening, rebinding and force sharing to the avidity of biomolecule interactions. PLoS One 2012; 7:e44070. [PMID: 23024747 PMCID: PMC3443103 DOI: 10.1371/journal.pone.0044070] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Accepted: 07/30/2012] [Indexed: 12/23/2022] Open
Abstract
Cell adhesion is mediated by numerous membrane receptors. It is desirable to derive the outcome of a cell-surface encounter from the molecular properties of interacting receptors and ligands. However, conventional parameters such as affinity or kinetic constants are often insufficient to account for receptor efficiency. Avidity is a qualitative concept frequently used to describe biomolecule interactions: this includes incompletely defined properties such as the capacity to form multivalent attachments. The aim of this study is to produce a working description of monovalent attachments formed by a model system, then to measure and interpret the behavior of divalent attachments under force. We investigated attachments between antibody-coated microspheres and surfaces coated with sparse monomeric or dimeric ligands. When bonds were subjected to a pulling force, they exhibited both a force-dependent dissociation consistent with Bell’s empirical formula and a force- and time-dependent strengthening well described by a single parameter. Divalent attachments were stronger and less dependent on forces than monovalent ones. The proportion of divalent attachments resisting a force of 30 piconewtons for at least 5 s was 3.7 fold higher than that of monovalent attachments. Quantitative modeling showed that this required rebinding, i.e. additional bond formation between surfaces linked by divalent receptors forming only one bond. Further, experimental data were compatible with but did not require stress sharing between bonds within divalent attachments. Thus many ligand-receptor interactions do not behave as single-step reactions in the millisecond to second timescale. Rather, they exhibit progressive stabilization. This explains the high efficiency of multimerized or clustered receptors even when bonds are only subjected to moderate forces. Our approach provides a quantitative way of relating binding avidity to measurable parameters including bond maturation, rebinding and force sharing, provided these parameters have been determined. Also, this provides a quantitative description of the phenomenon of bond strengthening.
Collapse
Affiliation(s)
- Valentina Lo Schiavo
- Aix-Marseille Université, LAI, Marseille, France
- Inserm UMR 1067, LAI, Marseille France
- CNRS UMR 7333, LAI, Marseille, France
| | - Philippe Robert
- Aix-Marseille Université, LAI, Marseille, France
- Inserm UMR 1067, LAI, Marseille France
- CNRS UMR 7333, LAI, Marseille, France
- Assistance Publique - Hôpitaux de Marseille (APHM), Hôpital de la Conception, Marseille, France
| | - Laurent Limozin
- Aix-Marseille Université, LAI, Marseille, France
- Inserm UMR 1067, LAI, Marseille France
- CNRS UMR 7333, LAI, Marseille, France
| | - Pierre Bongrand
- Aix-Marseille Université, LAI, Marseille, France
- Inserm UMR 1067, LAI, Marseille France
- CNRS UMR 7333, LAI, Marseille, France
- Assistance Publique - Hôpitaux de Marseille (APHM), Hôpital de la Conception, Marseille, France
- * E-mail:
| |
Collapse
|
43
|
Boettiger D. Mechanical control of integrin-mediated adhesion and signaling. Curr Opin Cell Biol 2012; 24:592-9. [PMID: 22857903 DOI: 10.1016/j.ceb.2012.07.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/14/2012] [Accepted: 07/11/2012] [Indexed: 01/13/2023]
Abstract
Integrin-mediated adhesion is controlled by the number of bonds between cell surface integrins and substrate-bound ligands. Integrin-ligand affinity is modulated by chemical allostery, mechanical allostery and integrin clustering. This review analyzes how each of these factors changes through the phases of cell attachment, adhesion strengthening, and clustering. The analysis predicts a dominant role of mechanical factors in both adhesive regulation and integrin signaling for adherent cells. New approaches and experimental analyses will be required to substantiate this hypothesis.
Collapse
Affiliation(s)
- David Boettiger
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
44
|
Ardjomandi N, Klein C, Kohler K, Maurer A, Kalbacher H, Niederländer J, Reinert S, Alexander D. Indirect coating of RGD peptides using a poly-L-lysine spacer enhances jaw periosteal cell adhesion, proliferation, and differentiation into osteogenic tissue. J Biomed Mater Res A 2012; 100:2034-44. [DOI: 10.1002/jbm.a.34062] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 10/12/2011] [Accepted: 11/11/2011] [Indexed: 02/04/2023]
|
45
|
Cell adhesion and focal contact formation on linear RGD molecular gradients: study of non-linear concentration dependence effects. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2012; 8:432-9. [DOI: 10.1016/j.nano.2011.08.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 07/01/2011] [Accepted: 08/06/2011] [Indexed: 11/21/2022]
|
46
|
Frith JE, Mills RJ, Cooper-White JJ. Lateral spacing of adhesion peptides influences human mesenchymal stem cell behaviour. J Cell Sci 2012; 125:317-27. [DOI: 10.1242/jcs.087916] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mesenchymal stem cells (MSCs) have attracted great interest in recent years for tissue engineering and regenerative medicine applications due to their ease of isolation and multipotent differentiation capacity. In the past, MSC research has focussed on the effects of soluble cues, such as growth factors and cytokines; however, there is now increasing interest in understanding how parameters such as substrate modulus, specific extracellular matrix (ECM) components and the ways in which these are presented to the cell can influence MSC properties. Here we use surfaces of self-assembled maleimide-functionalized polystyrene-block-poly(ethylene oxide) copolymers (PS-PEO-Ma) to investigate how the spatial arrangement of cell adhesion ligands affects MSC behaviour. By changing the ratio of PS-PEO-Ma in mixtures of block copolymer and polystyrene homopolymer, we can create surfaces with lateral spacing of the PEO-Ma domains ranging from 34 to 62 nm. Through subsequent binding of cysteine–GRGDS peptides to the maleimide-terminated end of the PEO chains in each of these domains, we are able to present tailored surfaces of controlled lateral spacing of RGD (arginine-glycine-aspartic acid) peptides to MSCs. We demonstrate that adhesion of MSCs to the RGD-functionalized block-copolymer surfaces is through specific attachment to the presented RGD motif and that this is mediated by α5, αV, β1 and β3 integrins. We show that as the lateral spacing of the peptides is increased, the ability of the MSCs to spread is diminished and that the morphology changes from well-spread cells with normal fibroblastic morphology and defined stress-fibres, to less-spread cells with numerous cell protrusions and few stress fibres. In addition, the ability of MSCs to form mature focal adhesions is reduced on substrates with increased lateral spacing. Finally, we investigate differentiation and use qRT-PCR determination of gene expression levels and a quantitative alkaline phosphatase assay to show that MSC osteogenesis is reduced on surfaces with increased lateral spacing while adipogenic differentiation is increased. We show here, for the first time, that the lateral spacing of adhesion peptides affects human MSC (hMSC) properties and might therefore be a useful parameter with which to modify hMSC behaviour in future tissue engineering strategies.
Collapse
Affiliation(s)
- Jessica E. Frith
- Tissue Engineering and Microfluidics Laboratory, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, 4072, Australia
| | - Richard J. Mills
- Tissue Engineering and Microfluidics Laboratory, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, 4072, Australia
| | - Justin J. Cooper-White
- Tissue Engineering and Microfluidics Laboratory, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, 4072, Australia
- School of Chemical Engineering, University of Queensland, Queensland, 4072, Australia
| |
Collapse
|
47
|
Titushkin I, Sun S, Cho M. Structure and Biology of the Cellular Environment: The Extracellular Matrix. NANOTECHNOLOGY FOR BIOLOGY AND MEDICINE 2012. [DOI: 10.1007/978-0-387-31296-5_1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
48
|
Combined QM/MM study of thyroid and steroid hormone analogue interactions with αvβ3 integrin. J Biomed Biotechnol 2012; 2012:959057. [PMID: 22547930 PMCID: PMC3323866 DOI: 10.1155/2012/959057] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 11/29/2011] [Accepted: 12/02/2011] [Indexed: 11/17/2022] Open
Abstract
Recent biochemical studies have identified a cell surface receptor for thyroid and steroid hormones that bind near the arginine-glycine-aspartate (RGD) recognition site on the heterodimeric αvβ3 integrin. To further characterize the intermolecular interactions for a series of hormone analogues, combined quantum mechanical and molecular mechanical (QM/MM) methods were used to calculate their interaction energies. All calculations were performed in the presence of either calcium (Ca(2+)) or magnesium (Mg(2+)) ions. These data reveal that 3,5'-triiodothyronine (T(3)) and 3,5,3',5'-tetraiodothyroacetic acid (T(4)ac) bound in two different modes, occupying two alternate sites, one of which is along the Arg side chain of the RGD cyclic peptide site. These orientations differ from those of the other ligands whose alternate binding modes placed the ligands deeper within the RGD binding pocket. These observations are consistent with biological data that indicate the presence of two discrete binding sites that control distinct downstream signal transduction pathways for T(3).
Collapse
|
49
|
GRYGIERZEC WIESLAW, DEUTSCH ANDREAS, SCHUBERT WALTER, FRIEDENBERGER MANUELA, PHILIPSEN LARS. MODELING TUMOR CELL POPULATION DYNAMICS BASED ON MOLECULAR ADHESION ASSUMPTIONS. J BIOL SYST 2011. [DOI: 10.1142/s021833900400118x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A model of cell population dynamics based on molecular adhesion is explained and discussed in this paper. We consider cancer cells experiencing interactions due to adhesion forces. In the cells' membranes there are proteins directly involved in adhesion. These proteins in the membrane are assembled in complex patterns called Combinatorial Protein Patterns (CPP). The goal of this work is to understand the mechanisms governing the adhesion process — in particular distinguishing CPPs involved in interactions. On the basis of experimental observation we have constructed an asynchronous cellular automaton (CA) model that simulates protein network dynamics in a population of cells.
Collapse
Affiliation(s)
- WIESLAW GRYGIERZEC
- Center for High Performance Computing (ZHR), Dresden University of Technology, Germany
- Department of Mathematical Statistics, Academy of Agriculture, Krakow, Poland
| | - ANDREAS DEUTSCH
- Center for High Performance Computing (ZHR), Dresden University of Technology, Germany
| | - WALTER SCHUBERT
- Institute for Medical Neurobiology, University of Magdeburg, Germany
- MelTeec GmbH, Magdeburg, Germany
| | | | | |
Collapse
|
50
|
Peng X, Huang J, Xiong C, Fang J. Cell adhesion nucleation regulated by substrate stiffness: a Monte Carlo study. J Biomech 2011; 45:116-22. [PMID: 22015238 DOI: 10.1016/j.jbiomech.2011.09.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 09/08/2011] [Accepted: 09/28/2011] [Indexed: 11/25/2022]
Abstract
Cell adhesions are modulated by the interactions between cells and their surroundings, among which substrate stiffness plays an important role in mediating cellular behaviors and functions. Little is known, however, about the inherent mechanism of how nascent adhesion nucleation, as the precursor of focal adhesions, is regulated by substrate stiffness. This paper presents a microscopic model to imitate integrin clustering kinetics, where integrin diffusion, activation on elastic substrates, receptor-ligand binding and association dynamics are fully considered. Particularly, the contribution of substrate compliance to the activation energy is analyzed, leading to a description of mechanical energy barrier for stretching a substrate-bound integrin molecule from bent to extended conformations. A series of Monte Carlo simulations for integrin clustering dynamics are performed with varied substrate Young's moduli, which demonstrates that more integrins are clustered on stiffer substrates once they begin to assemble over a rigidity threshold, indicating the responsiveness of adhesion nucleation to substrate elasticity, which is in reasonable agreement with results reported previously. Also, these simulations show that the sensitivity of integrin clustering to substrate stiffness is mediated by chemical affinity between receptor-ligand pairs and that between integrins cross-linked by adapter proteins, as well as integrin density on cell membranes. The investigation offers a fascinating insight into the inherent mechanism of mechanosensing concerning integrin-mediated cell-matrix initial adhesions.
Collapse
Affiliation(s)
- Xiaoling Peng
- Department of Biomedical Engineering, Peking University, Beijing 100871, PR China
| | | | | | | |
Collapse
|