scholarly journals Self-assembly of tessellated tissue sheets by growth and collision

2021 ◽  
Author(s):  
Matthew A Heinrich ◽  
Ricard Alert ◽  
Abraham E. Wolf ◽  
Andrej Kosmrlj ◽  
Daniel J. Cohen

Tissues do not exist in isolation; they interact with other tissues within and across organs. While cell-cell interactions have been intensely investigated, less is known about tissue-tissue interactions. Here, we studied collisions between monolayer tissues with different geometries, cell densities, and cell types. First, we determine rules for tissue shape changes during binary collisions and describe complex cell migration at tri-tissue boundaries. Next, we demonstrate that genetically identical tissues displace each other based solely on cell density gradients, and present a physical model of tissue interactions that allows us to estimate the bulk modulus of the tissues from collision dynamics. Finally, we introduce TissEllate, a design tool for self-assembling complex tessellations from arrays of many tissues, and we use cell sheet engineering techniques to transfer these composite tissues like cellular films. Overall, our work provides insight into the mechanics of tissue collisions, harnessing them to engineer tissue composites as designable living materials.

2006 ◽  
Vol 20 (20) ◽  
pp. 1217-1231 ◽  
Author(s):  
ADRIAN NEAGU ◽  
IOAN KOSZTIN ◽  
KAROLY JAKAB ◽  
BOGDAN BARZ ◽  
MONICA NEAGU ◽  
...  

As a theoretical framework for understanding the self-assembly of living cells into tissues, Steinberg proposed the differential adhesion hypothesis (DAH) according to which a specific cell type possesses a specific adhesion apparatus that combined with cell motility leads to cell assemblies of various cell types in the lowest adhesive energy state. Experimental and theoretical efforts of four decades turned the DAH into a fundamental principle of developmental biology that has been validated both in vitro and in vivo. Based on computational models of cell sorting, we have developed a DAH-based lattice model for tissues in interaction with their environment and simulated biological self-assembly using the Monte Carlo method. The present brief review highlights results on specific morphogenetic processes with relevance to tissue engineering applications. Our own work is presented on the background of several decades of theoretical efforts aimed to model morphogenesis in living tissues. Simulations of systems involving about 105 cells have been performed on high-end personal computers with CPU times of the order of days. Studied processes include cell sorting, cell sheet formation, and the development of endothelialized tubes from rings made of spheroids of two randomly intermixed cell types, when the medium in the interior of the tube was different from the external one. We conclude by noting that computer simulations based on mathematical models of living tissues yield useful guidelines for laboratory work and can catalyze the emergence of innovative technologies in tissue engineering.


2004 ◽  
Vol 820 ◽  
Author(s):  
Jianzhong Xi ◽  
Jacob J. Schmidt ◽  
Carlo D. Montemagno

AbstratAs microcomponents in engineered systems, biological muscles have unique advantages such as large force transduction, utilization of biochemical fuel, and self-assembly from single cells, over other inorganic actuators for biomedical engineering applications. Successful integration of muscles with inorganic fabricated structures and electronics promises the capability of precisely characterizing muscles' mechanical properties and fabricating self-assembled controllable autonomous structures powered by ubiquitous glucose. However, the use of extracted muscle tissue from animals on these devices is impractical and inefficient, as the tissues must be dissected and incorporated into each device by hand with crude interfaces between the biological tissue and inorganic materials. Integration of muscle with fabricated structures would be optimally achieved through self-assembling muscle cells on MEMS. The construction of self-assembled muscle-powered MEMS structures is complicated by the stringent requirements to spatially direct the cell growth, control the tight connection of these differentiated structures with MEMS structures, and enable the cells and the integrated hybrid freedom to move. Conventional and soft photolithography techniques have been extensively employed to pattern the growth of a variety of cell types and investigate their interaction with substrate in the micrometer level. However, all studies are only suitable for patterning static cells on an immobile surface, so a novel system of spatially patterning the contractible cells must be developed to enable the cells and the integrated hybrid devices to be free to move.We present a novel system of self-assembling myocytes on MEMS devices. This system has shown its capability of spatially and selectively directed growth and differentiation of myocytes into single muscle bundles, attachment of these functional bundles to MEMS structures, and the controlled partial release of the resultant hybrid devices. Two groups of self-assembled muscle-MEMS devices, force-measuring cantilevers and muscle-powered microrobots have been created. Here the further detailed studies of this system are discussed, especially the concept of the self-assembly and the material interfacial problems in this system.


2004 ◽  
Vol 823 ◽  
Author(s):  
Jianzhong Xi ◽  
Jacob J. Schmidt ◽  
Carlo D. Montemagno

AbstractAs microcomponents in engineered systems, biological muscles have unique advantages such as large force transduction, utilization of biochemical fuel, and self-assembly from single cells, over other inorganic actuators for biomedical engineering applications. Successful integration of muscles with inorganic fabricated structures and electronics promises the capability of precisely characterizing muscles' mechanical properties and fabricating self-assembled controllable autonomous structures powered by ubiquitous glucose. However, the use of extracted muscle tissue from animals on these devices is impractical and inefficient, as the tissues must be dissected and incorporated into each device by hand with crude interfaces between the biological tissue and inorganic materials. Integration of muscle with fabricated structures would be optimally achieved through self-assembling muscle cells on MEMS. The construction of self-assembled muscle-powered MEMS structures is complicated by the stringent requirements to spatially direct the cell growth, control the tight connection of these differentiated structures with MEMS structures, and enable the cells and the integrated hybrid freedom to move. Conventional and soft photolithography techniques have been extensively employed to pattern the growth of a variety of cell types and investigate their interaction with substrate in the micrometer level. However, all studies are only suitable for patterning static cells on an immobile surface, so a novel system of spatially patterning the contractible cells must be developed to enable the cells and the integrated hybrid devices to be free to move.We present a novel system of self-assembling myocytes on MEMS devices. This system has shown its capability of spatially and selectively directed growth and differentiation of myocytes into single muscle bundles, attachment of these functional bundles to MEMS structures, and the controlled partial release of the resultant hybrid devices. Two groups of self- assembled muscle-MEMS devices, force-measuring cantilevers and muscle-powered microrobots have been created. Here the further detailed studies of this system are discussed, especially the concept of the self-assembly and the material interfacial problems in this system.


2012 ◽  
Vol 9 (1) ◽  
pp. 43 ◽  
Author(s):  
Hueyling Tan

Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use ofpeptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study ofbiological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries ofexisting disciplines. Many self-assembling systems are rangefrom bi- andtri-block copolymers to DNA structures as well as simple and complex proteins andpeptides. The ultimate goal is to harness molecular self-assembly such that design andcontrol ofbottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes oflife and non-life science applications. Such aspirations can be achievedthrough understanding thefundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.


2020 ◽  
Vol 27 (9) ◽  
pp. 923-929
Author(s):  
Gaurav Pandey ◽  
Prem Prakash Das ◽  
Vibin Ramakrishnan

Background: RADA-4 (Ac-RADARADARADARADA-NH2) is the most extensively studied and marketed self-assembling peptide, forming hydrogel, used to create defined threedimensional microenvironments for cell culture applications. Objectives: In this work, we use various biophysical techniques to investigate the length dependency of RADA aggregation and assembly. Methods: We synthesized a series of RADA-N peptides, N ranging from 1 to 4, resulting in four peptides having 4, 8, 12, and 16 amino acids in their sequence. Through a combination of various biophysical methods including thioflavin T fluorescence assay, static right angle light scattering assay, Dynamic Light Scattering (DLS), electron microscopy, CD, and IR spectroscopy, we have examined the role of chain-length on the self-assembly of RADA peptide. Results: Our observations show that the aggregation of ionic, charge-complementary RADA motifcontaining peptides is length-dependent, with N less than 3 are not forming spontaneous selfassemblies. Conclusion: The six biophysical experiments discussed in this paper validate the significance of chain-length on the epitaxial growth of RADA peptide self-assembly.


Soft Matter ◽  
2020 ◽  
Vol 16 (28) ◽  
pp. 6599-6607 ◽  
Author(s):  
Pijush Singh ◽  
Souvik Misra ◽  
Nayim Sepay ◽  
Sanjoy Mondal ◽  
Debes Ray ◽  
...  

The self-assembly and photophysical properties of 4-nitrophenylalanine (4NP) are changed with the alteration of solvent and final self-assembly state of 4NP in competitive solvent mixture and are dictated by the solvent ratio.


2019 ◽  
Vol 4 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Ryan T. Shafranek ◽  
Joel D. Leger ◽  
Song Zhang ◽  
Munira Khalil ◽  
Xiaodan Gu ◽  
...  

Directed self-assembly in polymeric hydrogels allows tunability of thermal response and viscoelastic properties.


2020 ◽  
Vol 25 (4) ◽  
pp. 417-432
Author(s):  
Hidetoshi Mori ◽  
Jennifer Bolen ◽  
Louis Schuetter ◽  
Pierre Massion ◽  
Clifford C. Hoyt ◽  
...  

AbstractMultiplex immunofluorescence (mIF) allows simultaneous antibody-based detection of multiple markers with a nuclear counterstain on a single tissue section. Recent studies have demonstrated that mIF is becoming an important tool for immune profiling the tumor microenvironment, further advancing our understanding of the interplay between cancer and the immune system, and identifying predictive biomarkers of response to immunotherapy. Expediting mIF discoveries is leading to improved diagnostic panels, whereas it is important that mIF protocols be standardized to facilitate their transition into clinical use. Manual processing of sections for mIF is time consuming and a potential source of variability across numerous samples. To increase reproducibility and throughput we demonstrate the use of an automated slide stainer for mIF incorporating tyramide signal amplification (TSA). We describe two panels aimed at characterizing the tumor immune microenvironment. Panel 1 included CD3, CD20, CD117, FOXP3, Ki67, pancytokeratins (CK), and DAPI, and Panel 2 included CD3, CD8, CD68, PD-1, PD-L1, CK, and DAPI. Primary antibodies were first tested by standard immunohistochemistry and single-plex IF, then multiplex panels were developed and images were obtained using a Vectra 3.0 multispectral imaging system. Various methods for image analysis (identifying cell types, determining cell densities, characterizing cell-cell associations) are outlined. These mIF protocols will be invaluable tools for immune profiling the tumor microenvironment.


Pharmaceutics ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 166 ◽  
Author(s):  
Lucia Lombardi ◽  
Annarita Falanga ◽  
Valentina Del Genio ◽  
Stefania Galdiero

Peptide drugs hold great promise for the treatment of infectious diseases thanks to their novel mechanisms of action, low toxicity, high specificity, and ease of synthesis and modification. Naturally developing self-assembly in nature has inspired remarkable interest in self-assembly of peptides to functional nanomaterials. As a matter of fact, their structural, mechanical, and functional advantages, plus their high bio-compatibility and bio-degradability make them excellent candidates for facilitating biomedical applications. This review focuses on the self-assembly of peptides for the fabrication of antibacterial nanomaterials holding great interest for substituting antibiotics, with emphasis on strategies to achieve nano-architectures of self-assembly. The antibacterial activities achieved by these nanomaterials are also described.


2019 ◽  
Vol 4 (3) ◽  
pp. 580-585 ◽  
Author(s):  
Bineh G. Ndefru ◽  
Bryan S. Ringstrand ◽  
Sokhna I.-Y. Diouf ◽  
Sönke Seifert ◽  
Juan H. Leal ◽  
...  

Combining bottom-up self-assembly with top-down 3D photoprinting affords a low cost approach for the introduction of nanoscale features into a build with low resolution features.


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