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Puertas-Bartolomé M, Gutiérrez-Urrutia I, Teruel-Enrico LL, Duong CN, Desai K, Trujillo S, Wittmann C, Del Campo A. Self-Lubricating, Living Contact Lenses. Adv Mater 2024:e2313848. [PMID: 38583064 DOI: 10.1002/adma.202313848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 03/04/2024] [Indexed: 04/08/2024]
Abstract
The increasing prevalence of dry eye syndrome in aging and digital societies compromises long-term contact lens (CL) wear and forces users to regular eye drop instillation to alleviate discomfort. Here a novel approach with the potential to improve and extend the lubrication properties of CLs is presented. This is achieved by embedding lubricant-secreting biofactories within the CL material. The self-replenishable reservoirs autonomously produce and release hyaluronic acid (HA), a natural lubrication and wetting agent, long term. The hydrogel matrix regulates the growth of the biofactories and the HA production, and allows the diffusion of nutrients and HA for at least 3 weeks. The continuous release of HA sustainably reduces the friction coefficient of the CL surface. A self-lubricating CL prototype is presented, where the functional biofactories are contained in a functional ring at the lens periphery, outside of the vision area. The device is cytocompatible and fulfils physicochemical requirements of commercial CLs. The fabrication process is compatible with current manufacturing processes of CLs for vision correction. It is envisioned that the durable-by-design approach in living CL could enable long-term wear comfort for CL users and minimize the need for lubricating eye drops.
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Affiliation(s)
- María Puertas-Bartolomé
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
| | | | | | - Cao Nguyen Duong
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Krupansh Desai
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Sara Trujillo
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Christoph Wittmann
- Institute for Systems Biotechnology, Saarland University, Campus A1 5, 66123, Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
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2
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Yanamandra AK, Zhang J, Montalvo G, Zhou X, Biedenweg D, Zhao R, Sharma S, Hoth M, Lautenschläger F, Otto O, Del Campo A, Qu B. PIEZO1-mediated mechanosensing governs NK-cell killing efficiency and infiltration in three-dimensional matrices. Eur J Immunol 2024; 54:e2350693. [PMID: 38279603 DOI: 10.1002/eji.202350693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 01/28/2024]
Abstract
Natural killer (NK) cells play a vital role in eliminating tumorigenic cells. Efficient locating and killing of target cells in complex three-dimensional (3D) environments are critical for their functions under physiological conditions. However, the role of mechanosensing in regulating NK-cell killing efficiency in physiologically relevant scenarios is poorly understood. Here, we report that the responsiveness of NK cells is regulated by tumor cell stiffness. NK-cell killing efficiency in 3D is impaired against softened tumor cells, whereas it is enhanced against stiffened tumor cells. Notably, the durations required for NK-cell killing and detachment are significantly shortened for stiffened tumor cells. Furthermore, we have identified PIEZO1 as the predominantly expressed mechanosensitive ion channel among the examined candidates in NK cells. Perturbation of PIEZO1 abolishes stiffness-dependent NK-cell responsiveness, significantly impairs the killing efficiency of NK cells in 3D, and substantially reduces NK-cell infiltration into 3D collagen matrices. Conversely, PIEZO1 activation enhances NK killing efficiency as well as infiltration. In conclusion, our findings demonstrate that PIEZO1-mediated mechanosensing is crucial for NK killing functions, highlighting the role of mechanosensing in NK-cell killing efficiency under 3D physiological conditions and the influence of environmental physical cues on NK-cell functions.
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Affiliation(s)
- Archana K Yanamandra
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Jingnan Zhang
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Galia Montalvo
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany
- Center for Biophysics, Saarland University, Saarbrücken, Germany
| | - Xiangda Zhou
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Doreen Biedenweg
- Institute of Physics, University of Greifswald, Greifswald, Germany
| | - Renping Zhao
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Shulagna Sharma
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Markus Hoth
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Franziska Lautenschläger
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany
- Center for Biophysics, Saarland University, Saarbrücken, Germany
| | - Oliver Otto
- Institute of Physics, University of Greifswald, Greifswald, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany
- Chemistry Department, Saarland University, Saarbrücken, Germany
| | - Bin Qu
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
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Bhusari S, Hoffmann M, Herbeck-Engel P, Sankaran S, Wilhelm M, Del Campo A. Rheological behavior of Pluronic/Pluronic diacrylate hydrogels used for bacteria encapsulation in engineered living materials. Soft Matter 2024; 20:1320-1332. [PMID: 38241053 DOI: 10.1039/d3sm01119d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Pluronic (Plu) hydrogels mixed with variable fractions of Pluronic diacrylate (PluDA) have become popular matrices to encapsulate bacteria and control their growth in engineered living materials. Here we study the rheological response of 30 wt% Plu/PluDA hydrogels with PluDA fraction between 0 and 1. We quantify the range of viscoelastic properties that can be covered in this system by varying in the PluDA fraction. We present stress relaxation and creep-recovery experiments and describe the variation of the critical yield strain/stress, relaxation and recovery parameters of Plu/PluDA hydrogels as function of the covalent crosslinking degree using the Burgers and Weilbull models. The analyzed hydrogels present two stress relaxations with different timescales which can be tuned with the covalent crosslinking degree. We expect this study to help users of Plu/PluDA hydrogels to estimate the mechanical properties of their systems, and to correlate them with the behaviour of bacteria in future Plu/PluDA devices of similar composition.
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Affiliation(s)
- Shardul Bhusari
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Maxi Hoffmann
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry (ITCP), Engesserstraße 18, 76131 Karlsruhe, Germany
| | - Petra Herbeck-Engel
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
| | | | - Manfred Wilhelm
- Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry (ITCP), Engesserstraße 18, 76131 Karlsruhe, Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
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4
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Yanamandra AK, Bhusari S, Del Campo A, Sankaran S, Qu B. In vitro evaluation of immune responses to bacterial hydrogels for the development of living therapeutic materials. Biomater Adv 2023; 153:213554. [PMID: 37480604 DOI: 10.1016/j.bioadv.2023.213554] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/03/2023] [Accepted: 07/06/2023] [Indexed: 07/24/2023]
Abstract
In living therapeutic materials (LTMs), organisms genetically programmed to produce and deliver drugs are encapsulated in porous matrices acting as physical barriers between the therapeutic organisms and the host cells. LTMs consisting of engineered E. coli encapsulated in Pluronic F127-based hydrogels have been frequently used in LTM designs but their immunogenicity has not been tested. In this study, we investigate the response of human peripheral blood mononuclear cells (PBMCs) exposed to this bacteria/hydrogel combination. The release of inflammation-related cytokines and cytotoxic proteins and the subsets of natural killer cells and T cells were examined. Encapsulation of the bacteria in hydrogels considerably lowers their immunogenicity. ClearColi, an endotoxin-free variant of E. coli, did not polarize NK cells into the more cytolytic CD16dim subset as E. coli. Our results demonstrate that ClearColi-encapsulated hydrogels generate low immunogenic response and are suitable candidates for the development of LTMs for in vivo testing to assess a potential clinical use. Nevertheless, we observed a stronger immune response (elevated levels of IFNγ, IL-6 and cytotoxic proteins) in pro-inflammatory PBMCs characterized by a high spontaneous release of IL-2. This highlights the need to identify recipients who have a higher likelihood of experiencing undesired immune responses to LTMs with IL-2 serving as a potential predictive marker. Additionally, including anti-inflammatory measures in living therapeutic material designs could be beneficial for such recipients.
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Affiliation(s)
- Archana K Yanamandra
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany; INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Shardul Bhusari
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | | | - Bin Qu
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany; INM - Leibniz Institute for New Materials, Saarbrücken, Germany.
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5
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Khan ES, Sankaran S, Paez JI, Muth C, Han MKL, Del Campo A. Retraction: Photoactivatable Hsp47: A Tool to Regulate Collagen Secretion and Assembly. Adv Sci (Weinh) 2023; 10:e2304457. [PMID: 37582689 PMCID: PMC10427363 DOI: 10.1002/advs.202304457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
Adv. Sci. 2019, 6, 1801982 DOI: 10.1002/advs.201801982 The above article, published online on May 3, 2019, in Wiley Online Library (https://doi.org/10.1002/advs.201801982), has been retracted by agreement between the authors, the journal Editor-in-Chief Kirsten Severing, and Wiley-VCH GmbH. The retraction has been agreed on following concerns raised by a third party and a subsequent investigation by the corresponding authors. Data depicted in Figure 4 and Figure 5 could not be reproduced in follow-up experiments. Therefore, the conclusions associated with those figures in the article are considered invalid. E.S.K. participated in the study design, performed measurements, analyzed the data, compiled the figures and participated in manuscript writing. A.d.C. and S.S. participated in the study design, research supervision, and manuscript writing. J.I.P. participated in the study design. M.K.L.H. participated in research supervision and manuscript revision. C.M. assisted with the experimental procedures and data collection.
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6
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de Miguel-Jiménez A, Ebeling B, Paez JI, Fink-Straube C, Pearson S, Del Campo A. Gelation Kinetics and Mechanical Properties of Thiol-Tetrazole Methylsulfone Hydrogels Designed for Cell Encapsulation. Macromol Biosci 2023; 23:e2200419. [PMID: 36457236 DOI: 10.1002/mabi.202200419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/17/2022] [Indexed: 12/04/2022]
Abstract
Hydrogel precursors that crosslink within minutes are essential for the development of cell encapsulation matrices and their implementation in automated systems. Such timescales allow sufficient mixing of cells and hydrogel precursors under low shear forces and the achievement of homogeneous networks and cell distributions in the 3D cell culture. The previous work showed that the thiol-tetrazole methylsulfone (TzMS) reaction crosslinks star-poly(ethylene glycol) (PEG) hydrogels within minutes at around physiological pH and can be accelerated or slowed down with small pH changes. The resulting hydrogels are cytocompatible and stable in cell culture conditions. Here, the gelation kinetics and mechanical properties of PEG-based hydrogels formed by thiol-TzMS crosslinking as a function of buffer, crosslinker structure and degree of TzMS functionality are reported. Crosslinkers of different architecture, length and chemical nature (PEG versus peptide) are tested, and degree of TzMS functionality is modified by inclusion of RGD cell-adhesive ligand, all at concentration ranges typically used in cell culture. These studies corroborate that thiol/PEG-4TzMS hydrogels show gelation times and stiffnesses that are suitable for 3D cell encapsulation and tunable through changes in hydrogel composition. The results of this study guide formulation of encapsulating hydrogels for manual and automated 3D cell culture.
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Affiliation(s)
- Adrián de Miguel-Jiménez
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
| | - Bastian Ebeling
- Kuraray Europe GmbH, Advanced Interlayer Solutions, Competence Center for Innovation & Technology, Mülheimer Str. 26, 53840, Troisdorf, Germany
| | - Julieta I Paez
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Current address: Department of Developmental BioEngineering, Technical Medical Centre, University of Twente, Enschede, The Netherlands
| | - Claudia Fink-Straube
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Samuel Pearson
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
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7
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Bhusari S, Kim J, Polizzi K, Sankaran S, Del Campo A. Encapsulation of bacteria in bilayer Pluronic thin film hydrogels: A safe format for engineered living materials. Biomater Adv 2023; 145:213240. [PMID: 36577192 DOI: 10.1016/j.bioadv.2022.213240] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 12/04/2022] [Accepted: 12/08/2022] [Indexed: 12/24/2022]
Abstract
In engineered living materials (ELMs) non-living matrices encapsulate microorganisms to acquire capabilities like sensing or biosynthesis. The confinement of the organisms to the matrix and the prevention of overgrowth and escape during the lifetime of the material is necessary for the application of ELMs into real devices. In this study, a bilayer thin film hydrogel of Pluronic F127 and Pluronic F127 acrylate polymers supported on a solid substrate is introduced. The inner hydrogel layer contains genetically engineered bacteria and supports their growth, while the outer layer acts as an envelope and does not allow leakage of the living organisms outside of the film for at least 15 days. Due to the flat and transparent nature of the construct, the thin layer is suited for microscopy and spectroscopy-based analyses. The composition and properties of the inner and outer layer are adjusted independently to fulfil viability and confinement requirements. We demonstrate that bacterial growth and light-induced protein production are possible in the inner layer and their extent is influenced by the crosslinking degree of the used hydrogel. Bacteria inside the hydrogel are viable long term, they can act as lactate-sensors and remain active after storage in phosphate buffer at room temperature for at least 3 weeks. The versatility of bilayer bacteria thin-films is attractive for fundamental studies and for the development of application-oriented ELMs.
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Affiliation(s)
- Shardul Bhusari
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Juhyun Kim
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom; Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, United Kingdom; Current affiliation - School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Karen Polizzi
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, United Kingdom; Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, United Kingdom
| | | | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany.
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8
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Puertas-Bartolomé M, Włodarczyk-Biegun MK, Del Campo A, Vázquez-Lasa B, San Román J. Development of bioactive catechol functionalized nanoparticles applicable for 3D bioprinting. Mater Sci Eng C Mater Biol Appl 2021; 131:112515. [PMID: 34857294 DOI: 10.1016/j.msec.2021.112515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 10/19/2021] [Accepted: 10/22/2021] [Indexed: 12/11/2022]
Abstract
Efficient wound treatments to target specific events in the healing process of chronic wounds constitute a significant aim in regenerative medicine. In this sense, nanomedicine can offer new opportunities to improve the effectiveness of existing wound therapies. The aim of this study was to develop catechol bearing polymeric nanoparticles (NPs) and to evaluate their potential in the field of wound healing. Thus, NPs wound healing promoting activities, potential for drug encapsulation and controlled release, and further incorporation in a hydrogel bioink formulation to fabricate cell-laden 3D scaffolds are studied. NPs with 2 and 29 M % catechol contents (named NP2 and NP29) were obtained by nanoprecipitation and presented hydrodynamic diameters of 100 and 75 nm respectively. These nanocarriers encapsulated the hydrophobic compound coumarin-6 with 70% encapsulation efficiency values. In cell culture studies, the NPs had a protective effect in RAW 264.7 macrophages against oxidative stress damage induced by radical oxygen species (ROS). They also presented a regulatory effect on the inflammatory response of stimulated macrophages and promoted upregulation of the vascular endothelial growth factor (VEGF) in fibroblasts and endothelial cells. In particular, NP29 were used in a hydrogel bioink formulation using carboxymethyl chitosan and hyaluronic acid as polymeric matrices. Using a reactive mixing bioprinting approach, NP-loaded hydrogel scaffolds with good structural integrity, shape fidelity and homogeneous NPs dispersion, were obtained. The in vitro catechol NPs release profile of the printed scaffolds revealed a sustained delivery. The bioprinted scaffolds supported viability and proliferation of encapsulated L929 fibroblasts over 14 days. We envision that the catechol functionalized NPs and resulting bioactive bioink presented in this work offer promising advantages for wound healing applications, as they: 1) support controlled release of bioactive catechol NPs to the wound site; 2) can incorporate additional therapeutic functions by co-encapsulating drugs; 3) can be printed into 3D scaffolds with tailored geometries based on patient requirements.
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Affiliation(s)
- María Puertas-Bartolomé
- Institute of Polymer Science and Technology, ICTP-CSIC, Juan de la Cierva 3, 28006 Madrid, Spain; CIBER's Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, Health Institute Carlos III, Monforte de Lemos 3-5, 28029 Madrid, Spain; INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
| | | | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Blanca Vázquez-Lasa
- Institute of Polymer Science and Technology, ICTP-CSIC, Juan de la Cierva 3, 28006 Madrid, Spain; CIBER's Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, Health Institute Carlos III, Monforte de Lemos 3-5, 28029 Madrid, Spain.
| | - Julio San Román
- Institute of Polymer Science and Technology, ICTP-CSIC, Juan de la Cierva 3, 28006 Madrid, Spain; CIBER's Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, Health Institute Carlos III, Monforte de Lemos 3-5, 28029 Madrid, Spain
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Zheng Y, Han MKL, Zhao R, Blass J, Zhang J, Zhou DW, Colard-Itté JR, Dattler D, Çolak A, Hoth M, García AJ, Qu B, Bennewitz R, Giuseppone N, Del Campo A. Optoregulated force application to cellular receptors using molecular motors. Nat Commun 2021; 12:3580. [PMID: 34117256 PMCID: PMC8196032 DOI: 10.1038/s41467-021-23815-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 05/13/2021] [Indexed: 01/16/2023] Open
Abstract
Progress in our understanding of mechanotransduction events requires noninvasive methods for the manipulation of forces at molecular scale in physiological environments. Inspired by cellular mechanisms for force application (i.e. motor proteins pulling on cytoskeletal fibers), we present a unique molecular machine that can apply forces at cell-matrix and cell-cell junctions using light as an energy source. The key actuator is a light-driven rotatory molecular motor linked to polymer chains, which is intercalated between a membrane receptor and an engineered biointerface. The light-driven actuation of the molecular motor is converted in mechanical twisting of the entangled polymer chains, which will in turn effectively “pull” on engaged cell membrane receptors (e.g., integrins, T cell receptors) within the illuminated area. Applied forces have physiologically-relevant magnitude and occur at time scales within the relevant ranges for mechanotransduction at cell-friendly exposure conditions, as demonstrated in force-dependent focal adhesion maturation and T cell activation experiments. Our results reveal the potential of nanomotors for the manipulation of living cells at the molecular scale and demonstrate a functionality which at the moment cannot be achieved by other technologies for force application. Molecular scale force application in physiological environments is important for studying mechanotransduction. Here, the authors use a molecular machine to apply forces at cell-matrix and cell-cell junctions using light to trigger twisting actuation which then pulls on cell membrane receptors.
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Affiliation(s)
- Yijun Zheng
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | | | - Renping Zhao
- Biophysics, CIPMM, School of Medicine, Saarland University, Homburg, Germany
| | - Johanna Blass
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Jingnan Zhang
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Dennis W Zhou
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.,Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Jean-Rémy Colard-Itté
- SAMS Research Group, Institut Charles Sadron, University of Strasbourg - CNRS, Strasbourg, France
| | - Damien Dattler
- SAMS Research Group, Institut Charles Sadron, University of Strasbourg - CNRS, Strasbourg, France
| | - Arzu Çolak
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Markus Hoth
- Biophysics, CIPMM, School of Medicine, Saarland University, Homburg, Germany
| | - Andrés J García
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.,Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Bin Qu
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany.,Biophysics, CIPMM, School of Medicine, Saarland University, Homburg, Germany
| | - Roland Bennewitz
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany.,Saarland University, Physics Department, Saarbrücken, Germany
| | - Nicolas Giuseppone
- SAMS Research Group, Institut Charles Sadron, University of Strasbourg - CNRS, Strasbourg, France
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Saarbrücken, Germany. .,Saarland University, Chemistry Department, Saarbrücken, Germany.
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Paez JI, de Miguel-Jiménez A, Valbuena-Mendoza R, Rathore A, Jin M, Gläser A, Pearson S, Del Campo A. Thiol-Methylsulfone-Based Hydrogels for Cell Encapsulation: Reactivity Optimization of Aryl-Methylsulfone Substrate for Fine-Tunable Gelation Rate and Improved Stability. Biomacromolecules 2021; 22:2874-2886. [PMID: 34096259 DOI: 10.1021/acs.biomac.1c00256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydrogels are widely used as hydrated matrices for cell encapsulation in a number of applications, spanning from advanced 3D cultures and tissue models to cell-based therapeutics and tissue engineering. Hydrogel formation in the presence of living cells requires cross-linking reactions that proceed efficiently under close to physiological conditions. Recently, the nucleophilic aromatic substitution of phenyl-oxadiazole (Ox) methylsulfones (MS) by thiols was introduced as a new cross-linking reaction for cell encapsulation. Reported poly(ethylene glycol) (PEG)-based hydrogels featured tunable gelation times within seconds to a few minutes within pH 8.0 to 6.6 and allowed reasonably good mixing with cells. However, their rapid degradation prevented cell cultures to be maintained beyond 1 week. In this Article, we present the reactivity optimization of the heteroaromatic ring of the MS partner to slow down the cross-linking kinetics and the degradability of the derived hydrogels. New MS substrates based on phenyl-tetrazole (Tz) and benzothiazole (Bt) rings, with lower electrophilicity than Ox, were synthesized by simple pathways. When mixed with PEG-thiol, the novel PEG-MS extended the working time of precursor mixtures and allowed longer term cell culture. The Tz-based MS substrate was identified as the best candidate, as it is accessible by simple chemical reactions from cost-effective reactants, hydrogel precursors show good stability in aqueous solution and keep high chemoselectivity for thiols, and the derived Tz gels support cell cultures for >2 weeks. The Tz system also shows tunable gelation kinetics within seconds to hours and allows comfortable manipulation and cell encapsulation. Our findings expand the toolkit of thiol-mediated chemistry for the synthesis of hydrogels with improved properties for laboratory handling and future automatization.
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Affiliation(s)
- Julieta I Paez
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany
| | - Adrián de Miguel-Jiménez
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany.,Saarland University, Chemistry Department, 66123 Saarbrücken, Germany
| | - Rocío Valbuena-Mendoza
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany.,Saarland University, Chemistry Department, 66123 Saarbrücken, Germany
| | - Aditi Rathore
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany
| | - Minye Jin
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany.,Saarland University, Chemistry Department, 66123 Saarbrücken, Germany
| | - Alisa Gläser
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany
| | - Samuel Pearson
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2-2, 66123, Saarbrücken, Germany.,Saarland University, Chemistry Department, 66123 Saarbrücken, Germany
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11
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Escolano JC, Taubenberger AV, Abuhattum S, Schweitzer C, Farrukh A, Del Campo A, Bryant CE, Guck J. Compliant Substrates Enhance Macrophage Cytokine Release and NLRP3 Inflammasome Formation During Their Pro-Inflammatory Response. Front Cell Dev Biol 2021; 9:639815. [PMID: 33855019 PMCID: PMC8039395 DOI: 10.3389/fcell.2021.639815] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/08/2021] [Indexed: 12/27/2022] Open
Abstract
Immune cells process a myriad of biochemical signals but their function and behavior are also determined by mechanical cues. Macrophages are no exception to this. Being present in all types of tissues, macrophages are exposed to environments of varying stiffness, which can be further altered under pathological conditions. While it is becoming increasingly clear that macrophages are mechanosensitive, it remains poorly understood how mechanical cues modulate their inflammatory response. Here we report that substrate stiffness influences the expression of pro-inflammatory genes and the formation of the NLRP3 inflammasome, leading to changes in the secreted protein levels of the cytokines IL-1β and IL-6. Using polyacrylamide hydrogels of tunable elastic moduli between 0.2 and 33.1 kPa, we found that bone marrow-derived macrophages adopted a less spread and rounder morphology on compliant compared to stiff substrates. Upon LPS priming, the expression levels of the gene encoding for TNF-α were higher on more compliant hydrogels. When additionally stimulating macrophages with the ionophore nigericin, we observed an enhanced formation of the NLRP3 inflammasome, increased levels of cell death, and higher secreted protein levels of IL-1β and IL-6 on compliant substrates. The upregulation of inflammasome formation on compliant substrates was not primarily attributed to the decreased cell spreading, since spatially confining cells on micropatterns led to a reduction of inflammasome-positive cells compared to well-spread cells. Finally, interfering with actomyosin contractility diminished the differences in inflammasome formation between compliant and stiff substrates. In summary, we show that substrate stiffness modulates the pro-inflammatory response of macrophages, that the NLRP3 inflammasome is one of the components affected by macrophage mechanosensing, and a role for actomyosin contractility in this mechanosensory response. Thus, our results contribute to a better understanding of how microenvironment stiffness affects macrophage behavior, which might be relevant in diseases where tissue stiffness is altered and might potentially provide a basis for new strategies to modulate inflammatory responses.
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Affiliation(s)
- Joan-Carles Escolano
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany.,Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Anna V Taubenberger
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
| | - Shada Abuhattum
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany.,Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Christine Schweitzer
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Aleeza Farrukh
- INM - Leibniz-Institut für Neue Materialien, Saarbrücken, Germany
| | | | - Clare E Bryant
- Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Jochen Guck
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany.,Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
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12
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Zhang J, Zhao R, Li B, Farrukh A, Hoth M, Qu B, Del Campo A. Micropatterned soft hydrogels to study the interplay of receptors and forces in T cell activation. Acta Biomater 2021; 119:234-246. [PMID: 33099024 DOI: 10.1016/j.actbio.2020.10.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 09/28/2020] [Accepted: 10/15/2020] [Indexed: 12/30/2022]
Abstract
The analysis of T cell responses to mechanical properties of antigen presenting cells (APC) is experimentally challenging at T cell-APC interfaces. Soft hydrogels with adjustable mechanical properties and biofunctionalization are useful reductionist models to address this problem. Here, we report a methodology to fabricate micropatterned soft hydrogels with defined stiffness to form spatially confined T cell/hydrogel contact interfaces at micrometer scale. Using automatized microcontact printing we prepared arrays of anti-CD3 microdots on poly(acrylamide) hydrogels with Young's Modulus in the range of 2 to 50 kPa. We optimized the printing process to obtain anti-CD3 microdots with constant area (50 µm2, corresponding to 8 µm diameter) and comparable anti-CD3 density on hydrogels of different stiffness. The anti-CD3 arrays were recognized by T cells and restricted cell attachment to the printed areas. To test functionality of the hydrogel-T cell contact, we analyzed several key events downstream of T cell receptor (TCR) activation. Anti-CD3 arrays on hydrogels activated calcium influx, induced rearrangement of the actin cytoskeleton, and led to Zeta-chain-associated protein kinase 70 (ZAP70) phosphorylation. Interestingly, upon increase in the stiffness, ZAP70 phosphorylation was enhanced, whereas the rearrangements of F-actin (F-actin clearance) and phosphorylated ZAP70 (ZAP70/pY centralization) were unaffected. Our results show that micropatterned hydrogels allow tuning of stiffness and receptor presentation to analyze TCR mediated T cell activation as function of mechanical, biochemical, and geometrical parameters.
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Affiliation(s)
- Jingnan Zhang
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Renping Zhao
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421 Germany
| | - Bin Li
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
| | - Aleeza Farrukh
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
| | - Markus Hoth
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421 Germany
| | - Bin Qu
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany; Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421 Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany; Chemistry Department, Saarland University, 66123 Saarbrücken, Germany.
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13
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Abstract
Hydrogels for wound management and tissue gluing applications have to adhere to tissues for a given time scale and then disappear, either by removal from the skin or by slow degradation for applications inside the body. Advanced wound management materials also envision the encapsulation of therapeutic drugs or cells to support the natural healing process. The design of hydrogels that can fulfill all of these properties with minimal chemical complexity, a stringent condition to favor transfer into a real medical device, is challenging. Herein, we present a hydrogel design with a moderate structural complexity that fulfills a number of relevant properties for wound dressing: it can form in situ and encapsulate cells, it can adhere to tissues, and it can be degraded on demand by light exposure under cytocompatible conditions. The hydrogels are based on starPEG macromers terminated with catechol groups as cross-linking units and contain intercalated photocleavable nitrobenzyl triazole groups. Hydrogels are formed under mild conditions (N-(2-hydroxyethyl)piperazine-N'-ethanesulfonic acid (HEPES) buffer with 9-18 mM sodium periodate as the oxidant) and are compatible with encapsulated cells. Upon light irradiation, the cleavage of the nitrobenzyl group mediates depolymerization, which enables the on-demand release of cells and debonding from tissues. The molecular design and obtained properties reported here are interesting for the development of advanced wound dressings and cell therapies and expand the range of functionality of current alternatives.
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Affiliation(s)
- Maria Villiou
- INM-Leibniz Institute for New Materials, Campus D2-2, 66123 Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Julieta I Paez
- INM-Leibniz Institute for New Materials, Campus D2-2, 66123 Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials, Campus D2-2, 66123 Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
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14
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Abstract
Light-responsive hydrogels are useful platforms to study cellular responses. Current photosensitive motifs need UV light to be activated, which is intrinsically cytotoxic and has a low penetration depth in tissues. Herein we describe a strategy for near-infrared (NIR) controlled activation of cellular processes (3D cell spreading and angiogenesis) by embedding upconverting nanoparticles (UCNPs) in a hydrogel modified with light-activatable cell adhesive motifs. The UCNPs can convert NIR light (974 nm) into local UV emission and activate photochemical reactions on-demand. Such optoregulation is spatially controllable, dose-dependent and can be performed at different timepoints of the cell culture without appreciable photodamage of the cells. HUVEC cells embedded in this hydrogel can form vascular networks at predefined geometries determined by the irradiation pattern. The penetration depth of NIR light enabled activation of the angiogenesis response through skin tissue with a thickness of 2.5 mm. Our strategy opens a new avenue for 4D cell cultures, with the potential to be extended to dynamically manipulate cell-matrix interactions and derived cellular processes in vivo.
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Affiliation(s)
- Yijun Zheng
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
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15
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Weinberg F, Han MKL, Dahmke IN, Del Campo A, de Jonge N. Anti-correlation of HER2 and focal adhesion complexes in the plasma membrane. PLoS One 2020; 15:e0234430. [PMID: 32511274 PMCID: PMC7279600 DOI: 10.1371/journal.pone.0234430] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 05/25/2020] [Indexed: 11/18/2022] Open
Abstract
Excess presence of the human epidermal growth factor receptor 2 (HER2) as well as of the focal adhesion protein complexes are associated with increased proliferation, migratory, and invasive behavior of cancer cells. A cross-regulation between HER2 and integrin signaling pathways has been found, but the exact mechanism remains elusive. Here, we investigated whether HER2 colocalizes with focal adhesion complexes on breast cancer cells overexpressing HER2. For this purpose, vinculin or talin green fluorescent protein (GFP) fusion proteins, both key constituents of focal adhesions, were expressed in breast cancer cells. HER2 was either extracellularly or intracellularly labeled with fluorescent quantum dots nanoparticles (QDs). The cell-substrate interface was analyzed at the location of the focal adhesions by means of total internal reflection fluorescent microscopy or correlative fluorescence- and scanning transmission electron microscopy. Expression of HER2 at the cell-substrate interface was only observed upon intracellular labeling, and was heterogeneous with both HER2-enriched and -low regions. In contrast to an expected enrichment of HER2 at focal adhesions, an anti-correlated expression pattern was observed for talin and HER2. Our findings suggest a spatial anti-correlation between HER2 and focal adhesion complexes for adherent cells.
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Affiliation(s)
| | | | | | - Aránzazu Del Campo
- INM – Leibniz Institute for New Materials, Saarbrücken, Germany
- Department of Chemistry, University of Saarland, Saarbrücken, Germany
| | - Niels de Jonge
- INM – Leibniz Institute for New Materials, Saarbrücken, Germany
- Department of Physics, University of Saarland, Saarbrücken, Germany
- * E-mail:
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16
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Feng J, Jiang Q, Rogin P, de Oliveira PW, Del Campo A. Printed Soft Optical Waveguides of PLA Copolymers for Guiding Light into Tissue. ACS Appl Mater Interfaces 2020; 12:20287-20294. [PMID: 32285657 DOI: 10.1021/acsami.0c03903] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The application of optical technologies in treating pathologies and monitoring disease states requires the development of soft, minimal invasive and implantable devices to deliver light to tissues inside the body. Here, we present soft and degradable optical waveguides from poly(d,l-lactide) and derived copolymers fabricated by extrusion printing in the desired dimensions and shapes. The obtained optical waveguides propagate VIS to NIR light in air and in tissue at penetration depths of tens of centimeters. Besides, the printed waveguides have elastomeric properties at body temperature and show softness and flexibility in the range relevant for implantable devices in soft organs. Printed waveguides were able to guide light across 8 cm tissue and activate photocleavage chemical reactions in a photoresponsive hydrogel (in vitro). The simplicity and flexibility of the fiber processing method and the optical and mechanical performance of the obtained waveguides exemplify how rational study of medically approved biomaterials can lead to useful inks for printing cost-effective and flexible optical components for potential use in medical contexts.
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Affiliation(s)
- Jun Feng
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Qiyang Jiang
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
| | - Peter Rogin
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
| | - Peter W de Oliveira
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany
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17
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Mora-Boza A, Włodarczyk-Biegun MK, Del Campo A, Vázquez-Lasa B, Román JS. Glycerylphytate as an ionic crosslinker for 3D printing of multi-layered scaffolds with improved shape fidelity and biological features. Biomater Sci 2020; 8:506-516. [PMID: 31764919 DOI: 10.1039/c9bm01271k] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The fabrication of intricate and long-term stable 3D polymeric scaffolds by a 3D printing technique is still a challenge. In the biomedical field, hydrogel materials are very frequently used because of their excellent biocompatibility and biodegradability, however the improvement of their processability and mechanical properties is still required. This paper reports the fabrication of dual crosslinked 3D scaffolds using a low concentrated (<10 wt%) ink of gelatin methacryloyl (GelMA)/chitosan and a novel crosslinking agent, glycerylphytate (G1Phy) to overcome the current limitations in the 3D printing field using hydrogels. The applied methodology consisted of a first ultraviolet light (UV) photopolymerization followed by a post-printing ionic crosslinking treatment with G1Phy. This crosslinker provides a robust framework and avoids the necessity of neutralization with strong bases. The blend ink showed shear-thinning behavior and excellent printability in the form of a straight and homogeneous filament. UV curing was undertaken simultaneously to 3D deposition, which enhanced precision and shape fidelity (resolution ≈150 μm), and prevented the collapse of the subsequent printed layers (up to 28 layers). In the second step, the novel G1Phy ionic crosslinker agent provided swelling and long term stability properties to the 3D scaffolds. The multi-layered printed scaffolds were mechanically stable under physiological conditions for at least one month. Preliminary in vitro assays using L929 fibroblasts showed very promising results in terms of adhesion, spreading, and proliferation in comparison to other phosphate-based traditional crosslinkers (i.e. TPP). We envision that the proposed combination of the blend ink and 3D printing approach can have widespread applications in the regeneration of soft tissues.
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Affiliation(s)
- Ana Mora-Boza
- Institute of Polymer Science and Technology, ICTP-CSIC, Juan de la Cierva 3, 28006 Madrid, Spain
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18
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Khan ES, Sankaran S, Llontop L, Del Campo A. Exogenous supply of Hsp47 triggers fibrillar collagen deposition in skin cell cultures in vitro. BMC Mol Cell Biol 2020; 21:22. [PMID: 32228452 PMCID: PMC7106624 DOI: 10.1186/s12860-020-00267-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 03/20/2020] [Indexed: 12/17/2022] Open
Abstract
Background Collagen is a structural protein that provides mechanical stability and defined architectures to skin. In collagen-based skin disorders this stability is lost, either due to mutations in collagens or in the chaperones involved in collagen assembly. This leads to chronic wounds, skin fragility, and blistering. Existing approaches to treat such conditions rely on administration of small molecules to simulate collagen production, like 4-phenylbutyrate (4-PBA) or growth factors like TGF-β. However, these molecules are not specific for collagen synthesis, and result in unsolicited side effects. Hsp47 is a collagen-specific chaperone with a major role in collagen biosynthesis. Expression levels of Hsp47 correlate with collagen deposition. This article explores the stimulation of collagen deposition by exogenously supplied Hsp47 (collagen specific chaperone) to skin cells, including specific collagen subtypes quantification. Results Here we quantify the collagen deposition level and the types of deposited collagens after Hsp47 stimulation in different in vitro cultures of cells from human skin tissue (fibroblasts NHDF, keratinocytes HaCat and endothelial cells HDMEC) and mouse fibroblasts (L929 and MEF). We find upregulated deposition of fibrillar collagen subtypes I, III and V after Hsp47 delivery. Network collagen IV deposition was enhanced in HaCat and HDMECs, while fibril-associated collagen XII was not affected by the increased intracellular Hsp47 levels. The deposition levels of fibrillar collagen were cell-dependent i.e. Hsp47-stimulated fibroblasts deposited significantly higher amount of fibrillar collagen than Hsp47-stimulated HaCat and HDMECs. Conclusions A 3-fold enhancement of collagen deposition was observed in fibroblasts upon repeated dosage of Hsp47 within the first 6 days of culture. Our results provide fundamental understanding towards the idea of using Hsp47 as therapeutic protein to treat collagen disorders.
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Affiliation(s)
- Essak S Khan
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
| | | | - Lorena Llontop
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany. .,Chemistry Department, Saarland University, 66123, Saarbrücken, Germany.
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19
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Paez JI, Farrukh A, Valbuena-Mendoza R, Włodarczyk-Biegun MK, Del Campo A. Thiol-Methylsulfone-Based Hydrogels for 3D Cell Encapsulation. ACS Appl Mater Interfaces 2020; 12:8062-8072. [PMID: 31999422 DOI: 10.1021/acsami.0c00709] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Thiol-maleimide and thiol-vinylsulfone cross-linked hydrogels are widely used systems in 3D culture models, in spite of presenting uncomfortable reaction kinetics for cell encapsulation: too fast (seconds for thiol-maleimide) or too slow (minutes-hours for thiol-vinylsulfone). Here, we introduce the thiol-methylsulfone reaction as alternative cross-linking chemistry for cell encapsulation, particularized for PEG-hydrogels. The thiol-methylsulfone reaction occurs at high conversion and at intermediate reaction speed (seconds-minutes) under physiological pH range. These properties allow easy mixing of hydrogel precursors and cells to render homogeneous cell-laden gels at comfortable experimental time scales. The resulting hydrogels are cytocompatible and show comparable hydrolytic stability to thiol-vinylsulfone gels. They allow direct bioconjugation of thiol-derivatized ligands and tunable degradation kinetics by cross-linking with degradable peptide sequences. 3D cell culture of two cell types, fibroblasts and human umbilical vein endothelial cells (HUVECs), is demonstrated.
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Affiliation(s)
- Julieta I Paez
- INM - Leibniz Institute for New Materials , Campus D2-2 , 66123 Saarbrücken , Germany
| | - Aleeza Farrukh
- INM - Leibniz Institute for New Materials , Campus D2-2 , 66123 Saarbrücken , Germany
| | - Rocío Valbuena-Mendoza
- INM - Leibniz Institute for New Materials , Campus D2-2 , 66123 Saarbrücken , Germany
- Saarland University , Chemistry Department , 66123 Saarbrücken , Germany
| | | | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials , Campus D2-2 , 66123 Saarbrücken , Germany
- Saarland University , Chemistry Department , 66123 Saarbrücken , Germany
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20
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Han L, Zheng Y, Luo H, Feng J, Engstler R, Xue L, Jing G, Deng X, Del Campo A, Cui J. Macroscopic Self-Evolution of Dynamic Hydrogels to Create Hollow Interiors. Angew Chem Int Ed Engl 2020; 59:5611-5615. [PMID: 31840399 PMCID: PMC7154692 DOI: 10.1002/anie.201913574] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 11/29/2019] [Indexed: 11/30/2022]
Abstract
A solid‐to‐hollow evolution in macroscopic structures is challenging in synthetic materials. A fundamentally new strategy is reported for guiding macroscopic, unidirectional shape evolution of materials without compromising the material's integrity. This strategy is based on the creation of a field with a “swelling pole” and a “shrinking pole” to drive polymers to disassemble, migrate, and resettle in the targeted region. This concept is demonstrated using dynamic hydrogels containing anchored acrylic ligands and hydrophobic long alkyl chains. Adding water molecules and ferric ions (Fe3+) to induce a swelling–shrinking field transforms the hydrogels from solid to hollow. The strategy is versatile in the generation of various closed hollow objects (for example, spheres, helix tubes, and cubes with different diameters) for different applications.
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Affiliation(s)
- Lu Han
- Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 610054, China.,INM-Leibniz Institute for New Materials, Campus D2 2, Saarbrücken, 66123, Germany
| | - Yijun Zheng
- INM-Leibniz Institute for New Materials, Campus D2 2, Saarbrücken, 66123, Germany.,School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Hao Luo
- School of Physics, Northwest University, Xi'an, 710127, China
| | - Jun Feng
- INM-Leibniz Institute for New Materials, Campus D2 2, Saarbrücken, 66123, Germany
| | - Roxanne Engstler
- INM-Leibniz Institute for New Materials, Campus D2 2, Saarbrücken, 66123, Germany
| | - Lulu Xue
- Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Guangyin Jing
- School of Physics, Northwest University, Xi'an, 710127, China
| | - Xu Deng
- Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 610054, China
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials, Campus D2 2, Saarbrücken, 66123, Germany.,Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
| | - Jiaxi Cui
- Institute of Fundamental and Frontier Science, University of Electronic Science and Technology of China, Chengdu, 610054, China.,INM-Leibniz Institute for New Materials, Campus D2 2, Saarbrücken, 66123, Germany
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21
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Hetmanski JHR, de Belly H, Busnelli I, Waring T, Nair RV, Sokleva V, Dobre O, Cameron A, Gauthier N, Lamaze C, Swift J, Del Campo A, Starborg T, Zech T, Goetz JG, Paluch EK, Schwartz JM, Caswell PT. Membrane Tension Orchestrates Rear Retraction in Matrix-Directed Cell Migration. Dev Cell 2019; 51:460-475.e10. [PMID: 31607653 PMCID: PMC6863396 DOI: 10.1016/j.devcel.2019.09.006] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 07/02/2019] [Accepted: 09/10/2019] [Indexed: 01/11/2023]
Abstract
In development, wound healing, and cancer metastasis, vertebrate cells move through 3D interstitial matrix, responding to chemical and physical guidance cues. Protrusion at the cell front has been extensively studied, but the retraction phase of the migration cycle is not well understood. Here, we show that fast-moving cells guided by matrix cues establish positive feedback control of rear retraction by sensing membrane tension. We reveal a mechanism of rear retraction in 3D matrix and durotaxis controlled by caveolae, which form in response to low membrane tension at the cell rear. Caveolae activate RhoA-ROCK1/PKN2 signaling via the RhoA guanidine nucleotide exchange factor (GEF) Ect2 to control local F-actin organization and contractility in this subcellular region and promote translocation of the cell rear. A positive feedback loop between cytoskeletal signaling and membrane tension leads to rapid retraction to complete the migration cycle in fast-moving cells, providing directional memory to drive persistent cell migration in complex matrices.
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Affiliation(s)
- Joseph H R Hetmanski
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Henry de Belly
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; Institute for the Physics of Living Systems, University College London, London WC1E 6BT, UK
| | - Ignacio Busnelli
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg 67200, France; Université de Strasbourg, Strasbourg 67000, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg 67000, France
| | - Thomas Waring
- Institute of Translational Medicine, Cellular and Molecular Physiology, University of Liverpool, Liverpool L69 3BX, UK
| | - Roshna V Nair
- INM, Leibniz Institute for New Materials, Campus D226, 66123 Saarbrücken, Germany
| | - Vanesa Sokleva
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Oana Dobre
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Angus Cameron
- Barts Cancer Institute, Queen Mary University of London, London EC1M 6BQ, UK
| | - Nils Gauthier
- IFOM, the FIRC Institute for Molecular Oncology, Milan 20139, Italy
| | - Christophe Lamaze
- Institut Curie - Centre de Recherche, PSL Research University, CNRS UMR 3666, INSERM U1143, Membrane Dynamics and Mechanics of Intracellular Signaling Laboratory, 75248 Paris Cedex 05, France
| | - Joe Swift
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | | | - Tobias Starborg
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Tobias Zech
- Institute of Translational Medicine, Cellular and Molecular Physiology, University of Liverpool, Liverpool L69 3BX, UK
| | - Jacky G Goetz
- INSERM UMR_S1109, Tumor Biomechanics, Strasbourg 67200, France; Université de Strasbourg, Strasbourg 67000, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg 67000, France
| | - Ewa K Paluch
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK; Institute for the Physics of Living Systems, University College London, London WC1E 6BT, UK; Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Jean-Marc Schwartz
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK
| | - Patrick T Caswell
- Wellcome Trust Centre for Cell-Matrix Research, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK.
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22
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Oh YJ, Khan ES, Campo AD, Hinterdorfer P, Li B. Nanoscale Characteristics and Antimicrobial Properties of (SI-ATRP)-Seeded Polymer Brush Surfaces. ACS Appl Mater Interfaces 2019; 11:29312-29319. [PMID: 31259525 DOI: 10.1021/acsami.9b09885] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Microbial resistant coatings have raised considerable interest in the biotechnological industry and clinical scenarios to combat the spreading of infections, in particular in implanted medical devices. Polymer brushes covalently attached to surfaces represent a useful platform to identify ideal compositions for preventing bacterial settlement by quantifying bacteria-surface interactions. In this work, a series of polymer brushes with different charges, positively charged poly[2-(methacryloyloxy)ethyl trimethylammonium chloride] (PMETAC), negatively charged poly(3-sulfopropyl methacrylate potassium salt) (PSPMA), and neutral poly(2-hydroxyethyl methacrylate) (PHEMA) were grafted onto glass surfaces by surface-initiated atom transfer radical polymerization in aqueous conditions. The antimicrobial activity of the polymer brushes against Gram-negative Escherichia coli was tested at the nano- and microscopic level on different time scales, that is, from nm to 100 μm, and ms to 24 h, respectively. The interaction between the polymer brushes and E. coli was studied by single-cell force spectroscopy (SCFS) and by quantification of the bacterial density on surfaces incubated with bacterial suspensions. E. coli firmly attached to positive PMETAC brushes with high work required for de-adhesion of 28 ± 9 nN·nm, but did not significantly bind to negatively charged PSPMA and neutral PHEMA brushes. Our studies of bacterial adhesion using polymer brushes with controllable chemistry provide essential insights into bacterial surface interactions and the origins of bacterial adhesion.
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Affiliation(s)
- Yoo Jin Oh
- Institute of Biophysics , Johannes Kepler University Linz , Gruberstrasse 40 , A-4020 Linz , Austria
| | - Essak S Khan
- INM-Leibniz Institute for New Materials , Campus D2.2 , 66123 Saarbrücken , Germany
- Chemistry Department , Saarland University , 66123 Saarbrücken , Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials , Campus D2.2 , 66123 Saarbrücken , Germany
- Chemistry Department , Saarland University , 66123 Saarbrücken , Germany
| | - Peter Hinterdorfer
- Institute of Biophysics , Johannes Kepler University Linz , Gruberstrasse 40 , A-4020 Linz , Austria
| | - Bin Li
- INM-Leibniz Institute for New Materials , Campus D2.2 , 66123 Saarbrücken , Germany
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23
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Li B, Kappl M, Han L, Cui J, Zhou F, Del Campo A. Goosebumps-Inspired Microgel Patterns with Switchable Adhesion and Friction. Small 2019; 15:e1902376. [PMID: 31310426 DOI: 10.1002/smll.201902376] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/21/2019] [Indexed: 05/18/2023]
Abstract
A substrate mimicking the surface topography and temperature sensitivity of skin goosebumps is fabricated. Close-packed arrays of thermoresponsive microgel particles undergo topographical changes in response to temperature changes between 25 and 37 °C, resembling the goosebump structure that human skin develops in response to temperature changes or other circumstances. Specifically, positively charged poly[2-(methacryloyloxy)ethyltrimethylammonium chloride] (PMETAC) brushes serve as an anchoring substrate for negatively charged poly(NIPAm-co-AA) microgels. The packing density and particle morphology can be tuned by brush layer thickness and pH of the microgel suspension. For brush layer thickness below 50 nm, particle monolayers are observed, with slightly flattened particle morphology at pH 3 and highly collapsed particles at pH above 7. Polymer brush films with thickness above 50 nm lead to the formation of particle multilayers. The temperature responsiveness of the monolayer assemblies allows reversible changes in the film morphology, which in turn affects underwater adhesion and friction at 25 and 37 °C. These results are promising for the design of new functional materials and may also serve as a model for biological structures and processes.
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Affiliation(s)
- Bin Li
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Michael Kappl
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Lu Han
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, 610054, Chengdu, China
| | - Jiaxi Cui
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, 610054, Chengdu, China
| | - Feng Zhou
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000, Lanzhou, China
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
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24
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Sankaran S, Becker J, Wittmann C, Del Campo A. Optoregulated Drug Release from an Engineered Living Material: Self-Replenishing Drug Depots for Long-Term, Light-Regulated Delivery. Small 2019; 15:e1804717. [PMID: 30589209 DOI: 10.1002/smll.201804717] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 11/30/2018] [Indexed: 06/09/2023]
Abstract
On-demand and long-term delivery of drugs are common requirements in many therapeutic applications, not easy to be solved with available smart polymers for drug encapsulation. This work presents a fundamentally different concept to address such scenarios using a self-replenishing and optogenetically controlled living material. It consists of a hydrogel containing an active endotoxin-free Escherichia coli strain. The bacteria are metabolically and optogenetically engineered to secrete the antimicrobial and antitumoral drug deoxyviolacein in a light-regulated manner. The permeable hydrogel matrix sustains a viable and functional bacterial population and permits diffusion and delivery of the synthesized drug to the surrounding medium at quantities regulated by light dose. Using a focused light beam, the site for synthesis and delivery of the drug can be freely defined. The living material is shown to maintain considerable levels of drug production and release for at least 42 days. These results prove the potential and flexibility that living materials containing engineered bacteria can offer for advanced therapeutic applications.
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Affiliation(s)
| | - Judith Becker
- Institute of Systems Biotechnology, Saarland University, 66123, Saarbrücken, Germany
| | - Christoph Wittmann
- Institute of Systems Biotechnology, Saarland University, 66123, Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
- Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
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25
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Sankaran S, Del Campo A. Optoregulated Protein Release from an Engineered Living Material. ACTA ACUST UNITED AC 2018; 3:e1800312. [PMID: 32627372 DOI: 10.1002/adbi.201800312] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 12/04/2018] [Indexed: 12/20/2022]
Abstract
Developing materials to encapsulate and deliver functional proteins inside the body is a challenging yet rewarding task for therapeutic purposes. High production costs, mostly associated with the purification process, short-term stability in vivo, and controlled and prolonged release are major hurdles for the clinical application of protein-based biopharmaceuticals. In an attempt to overcome these hurdles, herein, the possibility of incorporating bacteria as protein factories into a material and externally controlling protein release using optogenetics is demonstrated. By engineering bacteria to express and secrete a red fluorescent protein in response to low doses of blue light irradiation and embedding them in agarose hydrogels, living materials are fabricated capable of releasing proteins into the surrounding medium when exposed to light. These bacterial hydrogels allow spatially confined protein expression and dosed protein release over several weeks, regulated by the area and extent of light exposure. The possibility of incorporating such complex functions in a material using relatively simple material and genetic engineering strategies highlights the immense potential and versatility offered by living materials for protein-based biopharmaceutical delivery.
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Affiliation(s)
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Chemistry Department, Saarland University, 66123, Saarbrücken, Germany
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26
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Farrukh A, Zhao S, Paez JI, Kavyanifar A, Salierno M, Cavalié A, Del Campo A. In Situ, Light-Guided Axon Growth on Biomaterials via Photoactivatable Laminin Peptidomimetic IK(HANBP)VAV. ACS Appl Mater Interfaces 2018; 10:41129-41137. [PMID: 30387978 DOI: 10.1021/acsami.8b15517] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The ability to guide the growth of neurites is relevant for reconstructing neural networks and for nerve tissue regeneration. Here, a biofunctional hydrogel that allows light-based directional control of axon growth in situ is presented. The gel is covalently modified with a photoactivatable derivative of the short laminin peptidomimetic IKVAV. This adhesive peptide contains the photoremovable group 2-(4'-amino-4-nitro-[1,1'-biphenyl]-3-yl)propan-1-ol (HANBP) on the Lys rest that inhibits its activity. The modified peptide is highly soluble in water and can be simply conjugated to -COOH containing hydrogels via its terminal -NH2 group. Light exposure allows presentation of the IKVAV adhesive motif on a soft hydrogel at desired concentration and at defined position and time point. The photoactivated gel supports neurite outgrowth in embryonic neural progenitor cells culture and allows site-selective guidance of neurites extension. In situ exposure of cell cultures using a scanning laser allows outgrowth of neurites in desired pathways.
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Affiliation(s)
- Aleeza Farrukh
- INM-Leibniz Institute for New Materials , Campus D2 2 , 66123 Saarbrücken , Germany
- Max Planck Graduate Center , Forum Universitatis 2 , Building 1111, 55122 Mainz , Germany
| | - Shifang Zhao
- INM-Leibniz Institute for New Materials , Campus D2 2 , 66123 Saarbrücken , Germany
- Chemistry Department , Saarland University , 66123 Saarbrücken , Germany
| | - Julieta I Paez
- INM-Leibniz Institute for New Materials , Campus D2 2 , 66123 Saarbrücken , Germany
| | - Atria Kavyanifar
- Institute of Physiological Chemistry , University Medical Center Johannes Gutenberg University , Hanns-Dieter-Hüsch-Weg 19 , D-55128 Mainz , Germany
| | - Marcelo Salierno
- Institute of Physiological Chemistry , University Medical Center Johannes Gutenberg University , Hanns-Dieter-Hüsch-Weg 19 , D-55128 Mainz , Germany
| | - Adolfo Cavalié
- Experimental and Clinical Pharmacology and Toxicology , Saarland University , 66421 Homburg , Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials , Campus D2 2 , 66123 Saarbrücken , Germany
- Chemistry Department , Saarland University , 66123 Saarbrücken , Germany
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27
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Abstract
Optoregulated biointerfaces offer the possibility to manipulate the interactions between cell membrane receptors and the extracellular space. This Invited Feature Article summarizes recent efforts by our group and others during the past decade to develop light-responsive biointerfaces to stimulate cells and elicit cellular responses using photocleavable protecting groups (PPG) as our working tool. This article begins by providing a brief introduction to available PPGs, with a special focus on the widely used o-nitrobenzyl family, followed by an overview of molecular design principles for the control of bioactivity in the context of cell-material interactions and the characterization methods to use in following the photoreaction at surfaces. We present various light-guided cellular processes using PPGs, including cell adhesion, release, migration, proliferation, and differentiation, both in vitro and in vivo. Finally, this Invited Feature Article closes with our perspective on the current status and future challenges of this topic.
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Affiliation(s)
- Yijun Zheng
- INM - Leibniz Institute for New Materials, Campus D2 2 , 66123 Saarbrücken , Germany
| | - Aleeza Farrukh
- INM - Leibniz Institute for New Materials, Campus D2 2 , 66123 Saarbrücken , Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2 , 66123 Saarbrücken , Germany
- Chemistry Department , Saarland University , 66123 Saarbrücken , Germany
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28
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Latorre E, Kale S, Casares L, Gómez-González M, Uroz M, Valon L, Nair RV, Garreta E, Montserrat N, Del Campo A, Ladoux B, Arroyo M, Trepat X. Active superelasticity in three-dimensional epithelia of controlled shape. Nature 2018; 563:203-208. [PMID: 30401836 DOI: 10.1038/s41586-018-0671-4] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 10/08/2018] [Indexed: 01/13/2023]
Abstract
Fundamental biological processes are carried out by curved epithelial sheets that enclose a pressurized lumen. How these sheets develop and withstand three-dimensional deformations has remained unclear. Here we combine measurements of epithelial tension and shape with theoretical modelling to show that epithelial sheets are active superelastic materials. We produce arrays of epithelial domes with controlled geometry. Quantification of luminal pressure and epithelial tension reveals a tensional plateau over several-fold areal strains. These extreme strains in the tissue are accommodated by highly heterogeneous strains at a cellular level, in seeming contradiction to the measured tensional uniformity. This phenomenon is reminiscent of superelasticity, a behaviour that is generally attributed to microscopic material instabilities in metal alloys. We show that in epithelial cells this instability is triggered by a stretch-induced dilution of the actin cortex, and is rescued by the intermediate filament network. Our study reveals a type of mechanical behaviour-which we term active superelasticity-that enables epithelial sheets to sustain extreme stretching under constant tension.
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Affiliation(s)
- Ernest Latorre
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain.,LaCàN, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona, Spain
| | - Sohan Kale
- LaCàN, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona, Spain
| | - Laura Casares
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Manuel Gómez-González
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Marina Uroz
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Léo Valon
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Roshna V Nair
- INM-Leibniz Institut für Neue Materialien, Saarbrücken, Germany
| | - Elena Garreta
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - Nuria Montserrat
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain.,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Barcelona, Spain
| | - Aránzazu Del Campo
- INM-Leibniz Institut für Neue Materialien, Saarbrücken, Germany.,Chemistry Department, Saarland University, Saarbrücken, Germany
| | - Benoit Ladoux
- CNRS UMR 7592, Institut Jacques Monod (IJM), Université Paris Diderot, Paris, France.,Mechanobiology Institute (MBI), National University of Singapore, Singapore, Singapore
| | - Marino Arroyo
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain. .,LaCàN, Universitat Politècnica de Catalunya-BarcelonaTech, Barcelona, Spain.
| | - Xavier Trepat
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain. .,Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Barcelona, Spain. .,Unitat de Biofísica i Bioenginyeria, Universitat de Barcelona, Barcelona, Spain. .,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
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29
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Farrukh A, Fan W, Zhao S, Salierno M, Paez JI, Del Campo A. Photoactivatable Adhesive Ligands for Light-Guided Neuronal Growth. Chembiochem 2018; 19:1271-1279. [PMID: 29633466 DOI: 10.1002/cbic.201800118] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Indexed: 12/21/2022]
Abstract
Neuro-regeneration after trauma requires growth and reconnection of neurons to reestablish information flow in particular directions across the damaged tissue. To support this process, biomaterials for nerve tissue regeneration need to provide spatial information to adhesion receptors on the cell membrane and to provide directionality to growing neurites. Here, photoactivatable adhesive peptides based on the CASIKVAVSADR laminin peptidomimetic are presented and applied to spatiotemporal control of neuronal growth to biomaterials in vitro. The introduction of a photoremovable group [6-nitroveratryl (NVOC), 3-(4,5-dimethoxy-2-nitrophenyl)butan-2-yl (DMNPB), or 2,2'-((3'-(1-hydroxypropan-2-yl)-4'-nitro-[1,1'-biphenyl]-4-yl)azanediyl)bis(ethan-1-ol) (HANBP)] at the amino terminal group of the K residue temporally inhibited the activity of the peptide. The bioactivity was regained through controlled light exposure. When used in neuronal culture substrates, the peptides allowed light-based control of the attachment and differentiation of neuronal cells. Site-selective irradiation activated adhesion and differentiation cues and guided seeded neurons to grow in predefined patterns. This is the first demonstration of ligand-based light-controlled interaction between neuronal cells and biomaterials.
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Affiliation(s)
- Aleeza Farrukh
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Max Planck Graduate Center, Forum Universitatis 2, Building 1111, 55122, Mainz, Germany
| | - Wenqiang Fan
- Institute of Physiological Chemistry, University Medical Center Johannes Gutenberg, Hanns-Dieter-Hüsch-Weg 19, 55128, Mainz, Germany
| | - Shifang Zhao
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Saarland University, Chemistry Department, 66123, Saarbrücken, Germany
| | - Marcelo Salierno
- Institute of Physiological Chemistry, University Medical Center Johannes Gutenberg, Hanns-Dieter-Hüsch-Weg 19, 55128, Mainz, Germany.,INIBIOMA, CRUB, Universidad Nacional del Comahue, Quintral 1250, 8400, S.C. Bariloche, Argentina
| | - Julieta I Paez
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials, Campus D2 2, 66123, Saarbrücken, Germany.,Saarland University, Chemistry Department, 66123, Saarbrücken, Germany
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30
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Abstract
Engineering novel biomaterials that mimic closer in vivo scenarios requires the simple and quantitative incorporation of multiple instructive signals to gain a higher level of control and complexity at the cell-matrix interface. Poly(acrylamide) (PAAm) gels are very popular among biology labs as 2D model substrates with defined biochemical and mechanical properties. These gels are cost effective, easy to prepare, reproducible, and available in a wide range of stiffness. However, their functionalization with bioactive ligands (cell adhesive proteins or peptides, growth factors, etc.) in a controlled and functional fashion is not trivial; therefore reproducible and trustable protocols are needed. Amine or thiol groups are ubiquitous in natural or synthetic peptides, proteins, and dyes, and hence routinely used as handles for their immobilization on biomaterials.We describe here the preparation of mechanically defined (0.5-100 kPa, range that approximates the stiffness of most tissues in nature), thin PAAm-based hydrogels supported on a glass substrate and covalently functionalized with amine- or thiol-containing bioligands via simple, robust, and effective protocols.
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Affiliation(s)
- Julieta I Paez
- INM-Leibniz Institute for New Materials, Saarbrücken, Germany.
| | - Aleeza Farrukh
- INM-Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Oya Ustahüseyin
- INM-Leibniz Institute for New Materials, Saarbrücken, Germany
| | - Aránzazu Del Campo
- INM-Leibniz Institute for New Materials, Saarbrücken, Germany.
- Chemistry Department, Saarland University, Saarland, Germany.
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31
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Feng J, Ton XA, Zhao S, Paez JI, Del Campo A. Mechanically Reinforced Catechol-Containing Hydrogels with Improved Tissue Gluing Performance. Biomimetics (Basel) 2017; 2:E23. [PMID: 31105184 PMCID: PMC6352675 DOI: 10.3390/biomimetics2040023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 10/30/2017] [Accepted: 11/02/2017] [Indexed: 12/13/2022] Open
Abstract
In situ forming hydrogels with catechol groups as tissue reactive functionalities are interesting bioinspired materials for tissue adhesion. Poly(ethylene glycol) (PEG)⁻catechol tissue glues have been intensively investigated for this purpose. Different cross-linking mechanisms (oxidative or metal complexation) and cross-linking conditions (pH, oxidant concentration, etc.) have been studied in order to optimize the curing kinetics and final cross-linking degree of the system. However, reported systems still show limited mechanical stability, as expected from a PEG network, and this fact limits their potential application to load bearing tissues. Here, we describe mechanically reinforced PEG⁻catechol adhesives showing excellent and tunable cohesive properties and adhesive performance to tissue in the presence of blood. We used collagen/PEG mixtures, eventually filled with hydroxyapatite nanoparticles. The composite hydrogels show far better mechanical performance than the individual components. It is noteworthy that the adhesion strength measured on skin covered with blood was >40 kPa, largely surpassing (>6 fold) the performance of cyanoacrylate, fibrin, and PEG⁻catechol systems. Moreover, the mechanical and interfacial properties could be easily tuned by slight changes in the composition of the glue to adapt them to the particular properties of the tissue. The reported adhesive compositions can tune and improve cohesive and adhesive properties of PEG⁻catechol-based tissue glues for load-bearing surgery applications.
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Affiliation(s)
- Jun Feng
- INM ⁻ Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany.
| | - Xuan-Anh Ton
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany.
| | - Shifang Zhao
- INM ⁻ Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany.
| | - Julieta I Paez
- INM ⁻ Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
| | - Aránzazu Del Campo
- INM ⁻ Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany.
- Chemistry Department, Saarland University, 66123 Saarbrücken, Germany.
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32
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Farrukh A, Ortega F, Fan W, Marichal N, Paez JI, Berninger B, Campo AD, Salierno MJ. Bifunctional Hydrogels Containing the Laminin Motif IKVAV Promote Neurogenesis. Stem Cell Reports 2017; 9:1432-1440. [PMID: 28988991 PMCID: PMC5829305 DOI: 10.1016/j.stemcr.2017.09.002] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 09/01/2017] [Accepted: 09/01/2017] [Indexed: 10/29/2022] Open
Abstract
Engineering of biomaterials with specific biological properties has gained momentum as a means to control stem cell behavior. Here, we address the effect of bifunctionalized hydrogels comprising polylysine (PL) and a 19-mer peptide containing the laminin motif IKVAV (IKVAV) on embryonic and adult neuronal progenitor cells under different stiffness regimes. Neuronal differentiation of embryonic and adult neural progenitors was accelerated by adjusting the gel stiffness to 2 kPa and 20 kPa, respectively. While gels containing IKVAV or PL alone failed to support long-term cell adhesion, in bifunctional gels, IKVAV synergized with PL to promote differentiation and formation of focal adhesions containing β1-integrin in embryonic cortical neurons. Furthermore, in adult neural stem cell culture, bifunctionalized gels promoted neurogenesis via the expansion of neurogenic clones. These data highlight the potential of synthetic matrices to steer stem and progenitor cell behavior via defined mechano-adhesive properties.
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Affiliation(s)
- Aleeza Farrukh
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
| | - Felipe Ortega
- Biochemistry and Molecular Biology Department IV, Faculty of Veterinary Medicine, Complutense University, Madrid, Spain; Institute of Neurochemistry (IUIN), 28040 Madrid, Spain; Health Research Institute of the Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Wenqiang Fan
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 19, 55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Nicolás Marichal
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 19, 55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Julieta I Paez
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany
| | - Benedikt Berninger
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 19, 55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Aránzazu Del Campo
- INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany; Saarland University, Campus Saarbrücken D2 2, 66123 Saarbrücken, Germany
| | - Marcelo J Salierno
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 19, 55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, 55131 Mainz, Germany.
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Neubauer JW, Xue L, Erath J, Drotlef DM, Campo AD, Fery A. Monitoring the Contact Stress Distribution of Gecko-Inspired Adhesives Using Mechano-Sensitive Surface Coatings. ACS Appl Mater Interfaces 2016; 8:17870-17877. [PMID: 27327111 DOI: 10.1021/acsami.6b05327] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The contact geometry of microstructured adhesive surfaces is of high relevance for adhesion enhancement. Theoretical considerations indicate that the stress distribution in the contact zone is crucial for the detachment mechanism, but direct experimental evidence is missing so far. In this work, we propose a method that allows, for the first time, the detection of local stresses at the contact area of biomimetic adhesive microstructures during contact formation, compression and detachment. We use a mechano-sensitive polymeric layer, which turns mechanical stresses into changes of fluorescence intensity. The biomimetic surface is brought into contact with this layer in a well-defined fashion using a microcontact printer, while the contact area is monitored with fluorescence microscopy in situ. Thus, changes in stress distribution across the contact area during compression and pull-off can be visualized with a lateral resolution of 1 μm. We apply this method to study the enhanced adhesive performance of T-shaped micropillars, compared to flat punch microstructures. We find significant differences in the stress distribution of the both differing contact geometries during pull-off. In particular, we find direct evidence for the suppression of crack nucleation at the edge of T-shaped pillars, which confirms theoretical models for the superior adhesive properties of these structures.
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Affiliation(s)
- Jens W Neubauer
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Str. 6, 01069 Dresden, Germany
- Department of Physical Chemistry II, University of Bayreuth , Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Longjian Xue
- School of Power and Mechanical Engineering, Wuhan University , South Donghu Road 8, 430072 Wuhan, China
- Max Planck Institute for Polymer Research , Ackermannweg 10, 55128 Mainz, Germany
| | - Johann Erath
- Department of Physical Chemistry II, University of Bayreuth , Universitätsstr. 30, 95447 Bayreuth, Germany
| | - Dirk-M Drotlef
- Max Planck Institute for Polymer Research , Ackermannweg 10, 55128 Mainz, Germany
| | - Aránzazu Del Campo
- Max Planck Institute for Polymer Research , Ackermannweg 10, 55128 Mainz, Germany
- INM - Leibniz Institute for New Materials , Campus D2 2, 66123 Saarbrücken, Germany
- Chemistry Department, Saarland University , 66123 Saarbrücken, Germany
| | - Andreas Fery
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Str. 6, 01069 Dresden, Germany
- Department of Physical Chemistry II, University of Bayreuth , Universitätsstr. 30, 95447 Bayreuth, Germany
- Cluster of Excellence Centre for Advancing Electronics Dresden (cfaed), Technische Universität Dresden , 01062 Dresden, Germany
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Abstract
Friction plays an important role in the adhesion of many climbing organisms, such as the gecko. During the shearing between two surfaces, periodic stick-slip behavior is often observed and may be critical to the adhesion of gecko setae and gecko-inspired adhesives. Here, we investigate the influence of short oligomers and pendent chains on the stick-slip friction of polydimethylsiloxane (PDMS), a commonly used material for bioinspired adhesives. Three different stick-slip patterns were observed on these surfaces (flat or microstructured) depending on the presence or absence of oligomers and their ability to diffuse out of the material. After washing samples to remove any untethered oligomeric chains, or after oxygen plasma treatment to convert the surface to a thin layer of silica, we decouple the contributions of stiffness, oligomers, and pendant chains to the stick-slip behavior. The stick phase is mainly controlled by the stiffness while the amount of untethered oligomers and pendant chains available at the contact interface defines the slip phase. A large amount of oligomers and pendant chains resulted in a large slip time, dominating the period of stick-slip motion.
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Affiliation(s)
- Longjian Xue
- School of Power and Mechanical Engineering, Wuhan University , South Donghu Road 8, 430072 Wuhan, China
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Jonathan T Pham
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Jagoba Iturri
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Aránzazu Del Campo
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
- INM- Leibniz Institute for New Materials , Campus D2 2, 66123 Saarbrücken, Germany
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Drotlef DM, Appel E, Peisker H, Dening K, Del Campo A, Gorb SN, Barnes WJP. Morphological studies of the toe pads of the rock frog, Staurois parvus (family: Ranidae) and their relevance to the development of new biomimetically inspired reversible adhesives. Interface Focus 2015; 5:20140036. [PMID: 25657830 DOI: 10.1098/rsfs.2014.0036] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The morphology of the toe epithelium of the rock frog, Staurois parvus (Family Ranidae), was investigated using a variety of microscopical techniques. The toe pad epithelium is stratified (four to five cell layers), the apical parts of the cells of the outermost layer being separated by fluid-filled channels. The surface of these cells is covered by a dense array of nanopillars, which also cover the surface of subarticular tubercles and unspecialized ventral epithelium of the toes, but not the dorsal epithelium. The apical portions of the outer two layers contain fibrils that originate from the nanopillars and are oriented approximately normal to the surface. This structure is similar to the pad structure of tree frogs of the families Hylidae and Rhacophoridae, indicating evolutionary convergence and a common evolutionary design for reversible attachment in climbing frogs. The main adaptation to the torrent habitat seems to be the straightness of the channels crossing the toe pad, which will assist in drainage of excess water. The presence of nanopillar arrays on all ventral surfaces of the toes resembles that on clingfish suckers and may be a specific adaptation for underwater adhesion and friction. The relevance of these findings to the development of new biomimetically inspired reversible adhesives is discussed.
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Affiliation(s)
- Dirk M Drotlef
- Max Planck Institut für Polymerforschung , Mainz , Germany
| | - Esther Appel
- Functional Morphology and Biomechanics , University of Kiel , Kiel , Germany
| | - Henrik Peisker
- Functional Morphology and Biomechanics , University of Kiel , Kiel , Germany
| | - Kirstin Dening
- Functional Morphology and Biomechanics , University of Kiel , Kiel , Germany
| | | | - Stanislav N Gorb
- Functional Morphology and Biomechanics , University of Kiel , Kiel , Germany
| | - W Jon P Barnes
- Centre for Cell Engineering , University of Glasgow , Scotland , UK
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García-Fernández L, Specht A, Del Campo A. A Polyurethane-Based Positive Photoresist. Macromol Rapid Commun 2014; 35:1801-1807. [PMID: 25220363 DOI: 10.1002/marc.201400331] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 07/17/2014] [Indexed: 02/28/2024]
Abstract
Polyurethane (PU) monomer mixtures containing commercially available o-nitrobenzyl-based photocleavable monomers have been formulated and tested as low-cost positive tone photoresists. The photolysis reaction is studied by UV spectroscopy. Well-defined micropatterns on 2 μm thick photodegradable PU films are obtained using 365 nm light exposure. This strategy is also extended to improved formulations based on synthesized o-nitrobiphenylpropyl derivatives with enhanced photochemical properties for single photon excitation and high two-photon absorption cross-sections. Improved pattern resolution in 2D and the capability of 3D resolution using a scanning laser at 780 nm is demonstrated. This work demonstrates the potential of PUs as readily available, versatile, and easy-to-use photoresist materials for low-cost lithography applications.
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Drotlef DM, Blümler P, Papadopoulos P, Del Campo A. Magnetically actuated micropatterns for switchable wettability. ACS Appl Mater Interfaces 2014; 6:8702-7. [PMID: 24803340 DOI: 10.1021/am5014776] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Arrays of actuated magnetic micropillars that can be tilted, twisted, and rotated in the presence of a magnetic field gradient were obtained. The type and extent of the movements are dependent on the distribution (isotropic, anisotropic) of the magnetizable particles inside the pillars and the strength and the direction of the magnetic field gradient. Independent motion of groups of pillars in the same or opposite directions or homogeneous motion of the whole pattern has been realized. Changing the pattern geometry causes changes in the roll-off angle (ROA) of water droplets on the surface. We show magnetically induced changes in the ROA and direction-dependent ROAs as a consequence of the anisotropy of tilted patterns. We also demonstrate transfer of microparticles between magnetically actuated neighboring pillars.
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Affiliation(s)
- Dirk-M Drotlef
- Max-Planck-Institut für Polymerforschung , Ackermannweg 10, 55128 Mainz, Germany
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Abstract
Two photoremovable protecting groups, namely, nitroveratryloxycarbonyl (NVo) and diethylamino-coumarin-4-yl (DEACM), have been tested for wavelength-selective, independent removal. The chromophores were attached to the amine group of aminopropyltriethoxysilane and used for the modification of silica surfaces. A photolytic experiment on the photosensitive layers allowed us to identify the irradiation conditions for the selective cleavage of the chromophores. UV measurements revealed that the photolabile DEACM group can be cleaved off with UV light at 412 nm without damaging the NVo group. The NVo group could then be removed at 365 nm. Masked irradiation of substrates modified with a 1:1 molar mixture of both silanes allowed the generation of bifunctional patterns after the selective cleavage of DEACM and NVo in a sequential irradiation process. The deprotection reaction was confirmed by coupling two different fluorescent dyes to the liberated amine groups. The expected two-color pattern could be observed by fluorescence microscopy.
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Affiliation(s)
- Petra Stegmaier
- Max-Planck-Institut fur Metallforschung, Heisenbergstrasse 3, 70569 Stuttgart, Germany
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