scholarly journals In vitro Self-Assembly of Human Pericyte-Supported Endothelial Microvessels in Three-Dimensional Coculture: A Simple Model for Interrogating Endothelial-Pericyte Interactions

2013 ◽  
Vol 50 (4) ◽  
pp. 324-331 ◽  
Author(s):  
J.P. Waters ◽  
M.S. Kluger ◽  
M. Graham ◽  
W.G. Chang ◽  
J.R. Bradley ◽  
...  
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.


2021 ◽  
Vol 8 ◽  
Author(s):  
Uwe Marx ◽  
Enrico Accastelli ◽  
Rhiannon David ◽  
Hendrik Erfurth ◽  
Leopold Koenig ◽  
...  

The first concepts for reproducing human systemic organismal biology in vitro were developed over 12 years ago. Such concepts, then called human- or body-on-a-chip, claimed that microphysiological systems would become the relevant technology platform emulating the physiology and morphology of human organisms at the smallest biologically acceptable scale in vitro and, therefore, would enable the selection of personalized therapies for any patient at unprecedented precision. Meanwhile, the first human organoids—stem cell-derived complex three-dimensional organ models that expand and self-organize in vitro—have proven that in vitro self-assembly of minute premature human organ-like structures is feasible, once the respective stimuli of ontogenesis are provided to human stem cells. Such premature organoids can precisely reflect a number of distinct physiological and pathophysiological features of their respective counterparts in the human body. We now develop the human-on-a-chip concepts of the past into an organismoid theory. We describe the current concept and principles to create a series of organismoids—minute, mindless and emotion-free physiological in vitro equivalents of an individual's mature human body—by an artificially short process of morphogenetic self-assembly mimicking an individual's ontogenesis from egg cell to sexually mature organism. Subsequently, we provide the concept and principles to maintain such an individual's set of organismoids at a self-sustained functional healthy homeostasis over very long time frames in vitro. Principles how to perturb a subset of healthy organismoids by means of the natural or artificial induction of diseases are enrolled to emulate an individual's disease process. Finally, we discuss using such series of healthy and perturbed organismoids in predictively selecting, scheduling and dosing an individual patient's personalized therapy or medicine precisely. The potential impact of the organismoid theory on our healthcare system generally and the rapid adoption of disruptive personalized T-cell therapies particularly is highlighted.


Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 419
Author(s):  
Ruyue Luo ◽  
Yuan Wan ◽  
Xinyi Luo ◽  
Guicen Liu ◽  
Zhaoxu Li ◽  
...  

Self-assembly peptide nanotechnology has attracted much attention due to its regular and orderly structure and diverse functions. Most of the existing self-assembly peptides can form aggregates with specific structures only under specific conditions and their assembly time is relatively long. They have good biocompatibility but no immunogenicity. To optimize it, a self-assembly peptide named DRF3 was designed. It contains a hydrophilic and hydrophobic surface, using two N-terminal arginines, leucine, and two c-terminal aspartate and glutamic acid. Meanwhile, the c-terminal of the peptide was amidated, so that peptide segments were interconnected to increase diversity. Its characterization, biocompatibility, controlled release effect on antigen, immune cell recruitment ability, and antitumor properties were examined here. Congo red/aniline blue staining revealed that peptide hydrogel DRF3 could be immediately gelled in PBS. The stable β-sheet secondary structure of DRF3 was confirmed by circular dichroism spectrum and IR spectra. The observation results of cryo-scanning electron microscopy, transmission electron microscopy, and atomic force microscopy demonstrated that DRF3 formed nanotubule-like and vesicular structures in PBS, and these structures interlaced with each other to form ordered three-dimensional nanofiber structures. Meanwhile, DRF3 showed excellent biocompatibility, could sustainably and slowly release antigens, recruit dendritic cells and promote the maturation of dendritic cells (DCs) in vitro. In addition, DRF3 has a strong inhibitory effect on clear renal cell carcinoma (786-0). These results provide a reliable basis for the application of peptide hydrogels in biomedical and preclinical trials.


TAPPI Journal ◽  
2018 ◽  
Vol 17 (02) ◽  
pp. 81-88
Author(s):  
Aleksandra Mikhailidi ◽  
Shahriar Karim Saurov ◽  
Seppo Anderson ◽  
Nina Kotelnikova

Super-swollen hydrogels were prepared in vitro from lignocelluloses of various origins via direct dissolving in N,N-dimethylacetamide/lithium chloride (DMAc/LiCl) followed by regeneration from solutions. The hydrogels retained a large amount of water (up to 2500 wt%) and had high porosity and specific surface areas. Superabsorbance of the hydrogels was confirmed with a wide angle X-ray scattering method. The hydrogels seem to be smart matters due to PH-dependent behavior by swelling and pH change experiments. The gelation mechanism includes spontaneous self-assembly from the solutions in DMAc/LiCl, due to the reconstruction of new hydrogen bond webs between lignocellulose chains and water. The hydrogels exhibited high stability but their morphology changed while drying due to water removal and the collapse of the H-bonds.


Polymers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1377 ◽  
Author(s):  
Anayet Kabir ◽  
Matthew Dunlop ◽  
Bishnu Acharya ◽  
Rabin Bissessur ◽  
Marya Ahmed

The exponential increase in heavy metal usage for industrial applications has led to the limited supply of clean water for human needs. Iron is one of the examples of heavy metals, which is responsible for an unpleasant taste of water and its discoloration, and is also associated with elevated health risks if it persists in drinking water for a prolonged period of time. The adsorption of a soluble form of iron (Fe2+) from water resources is generally accomplished in the presence of natural or synthetic polymers or nanoparticles, followed by their filtration from treated water. The self-assembly of these colloidal carriers into macroarchitectures can help in achieving the facile removal of metal-chelated materials from treated water and hence can reduce the cost and improve the efficiency of the water purification process. In this study, we aim to develop a facile one-pot strategy for the synthesis of polymeric composites with embedded nanocrystalline cellulose (NCC) for the chelation of iron(II) from contaminated water. The synthesis of the polymeric composites with embedded nanoparticles was achieved by the facile coating of ionic monomers on the surface of NCC, followed by their polymerization, crosslinking, and self-assembly in the form of three-dimensional architectures at room temperature. The composites prepared were analyzed for their physiochemical properties, antifouling properties, and for their iron(II)-chelation efficacies in vitro. The results indicate that the embedded-NCC polymeric composites have antifouling properties and exhibit superior iron(II)-chelation properties at both acidic and basic conditions.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2006
Author(s):  
Markus Merk ◽  
Orlando Chirikian ◽  
Christian Adlhart

Recent advancements in tissue engineering and material science have radically improved in vitro culturing platforms to more accurately replicate human tissue. However, the transition to clinical relevance has been slow in part due to the lack of biologically compatible/relevant materials. In the present study, we marry the commonly used two-dimensional (2D) technique of electrospinning and a self-assembly process to construct easily reproducible, highly porous, three-dimensional (3D) nanofiber scaffolds for various tissue engineering applications. Specimens from biologically relevant polymers polycaprolactone (PCL) and gelatin were chemically cross-linked using the naturally occurring cross-linker genipin. Potential cytotoxic effects of the scaffolds were analyzed by culturing human dermal fibroblasts (HDF) up to 23 days. The 3D PCL/gelatin/genipin scaffolds produced here resemble the complex nanofibrous architecture found in naturally occurring extracellular matrix (ECM) and exhibit physiologically relevant mechanical properties as well as excellent cell cytocompatibility. Samples cross-linked with 0.5% genipin demonstrated the highest metabolic activity and proliferation rates for HDF. Scanning electron microscopy (SEM) images indicated excellent cell adhesion and the characteristic morphological features of fibroblasts in all tested samples. The three-dimensional (3D) PCL/gelatin/genipin scaffolds produced here show great potential for various 3D tissue-engineering applications such as ex vivo cell culturing platforms, wound healing, or tissue replacement.


Author(s):  
Ziyue Xu ◽  
Weipeng Mao ◽  
Zizhen Zhao ◽  
Zekun Wang ◽  
Yue-Yang Liu ◽  
...  

Water-soluble three-dimensional supramolecular-organic frameworks (SOFs) and temoporfin (mTHPC) are discovered to form uniform self-assembly nanoparticles. These nanoparticles demonstrate an improved 1O2 generation efficiency due to a reduced aggregation-caused quenching effect....


Author(s):  
Kate V. Panzer ◽  
Justin C. Burrell ◽  
Kaila V. T. Helm ◽  
Erin M. Purvis ◽  
Qunzhou Zhang ◽  
...  

Following peripheral nerve injury comprising a segmental defect, the extent of axon regeneration decreases precipitously with increasing gap length. Schwann cells play a key role in driving axon re-growth by forming aligned tubular guidance structures called bands of Büngner, which readily occurs in distal nerve segments as well as within autografts – currently the most reliable clinically-available bridging strategy. However, host Schwann cells generally fail to infiltrate large-gap acellular scaffolds, resulting in markedly inferior outcomes and motivating the development of next-generation bridging strategies capable of fully exploiting the inherent pro-regenerative capability of Schwann cells. We sought to create preformed, implantable Schwann cell-laden microtissue that emulates the anisotropic structure and function of naturally-occurring bands of Büngner. Accordingly, we developed a biofabrication scheme leveraging biomaterial-induced self-assembly of dissociated rat primary Schwann cells into dense, fiber-like three-dimensional bundles of Schwann cells and extracellular matrix within hydrogel micro-columns. This engineered microtissue was found to be biomimetic of morphological and phenotypic features of endogenous bands of Büngner, and also demonstrated 8 and 2× faster rates of axonal extension in vitro from primary rat spinal motor neurons and dorsal root ganglion sensory neurons, respectively, compared to 3D matrix-only controls or planar Schwann cells. To our knowledge, this is the first report of accelerated motor axon outgrowth using aligned Schwann cell constructs. For translational considerations, this microtissue was also fabricated using human gingiva-derived Schwann cells as an easily accessible autologous cell source. These results demonstrate the first tissue engineered bands of Büngner (TE-BoBs) comprised of dense three-dimensional bundles of longitudinally aligned Schwann cells that are readily scalable as implantable grafts to accelerate axon regeneration across long segmental nerve defects.


2019 ◽  
Author(s):  
Girija Goyal ◽  
Bruce Bausk ◽  
Pranav Prabhala ◽  
Liangxia Xie ◽  
Danielle Curran ◽  
...  

ABSTRACTCandidate vaccines and immunotherapeutic drugs often fail in clinical trials as human lymph node (LN) physiology is not faithfully modeled in animal models or immune cell cultures. Here we describe a microfluidic Organ Chip culture device that supports self-assembly of human blood-derived B and T lymphocytes into three-dimensional (3D), germinal center-like lymphoid follicles (LFs) containing Activation-Induced Cytidine Deaminase (AID) expressing lymphocytes. These microengineered LFs support plasma cell differentiation upon activation with IL-4 and CD40 agonistic antibody (AB) or inactivated S. aureus Cowan I (SAC). Immunization of the human LN chip with a quadrivalent split virion influenza vaccine resulted in plasma cell formation, viral strain-specific anti-hemagglutinin immunoglobulin G (IgG) production, and a secreted cytokine profile that recapitulates serum responses of vaccinated humans. Thus, the human LN chip may provide a new tool to study human immune reactions, evaluate vaccine responses, and validate the efficacies and toxicities of immunotherapies in vitro.


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