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Conjugation of Polymers with Biomolecules and Polymeric Vaccine Development Technologies
Published in Mesut Karahan, Synthetic Peptide Vaccine Models, 2021
Biomaterials have evolved from crude wooden prostheses dating back millennia (Huebsch and Mooney 2009). Today, biomaterials are used for cell delivery, drug delivery, microcapsules, and 3D-printing. Polymeric biomaterials are generally described as very useful materials offering many advantages in biomedical, medical, and biology fields (Mann et al. 2018). Biomaterials are of two types: synthetic and natural polymers; lipids, self-assembled nanostructures, and engineered artificial cells offer unique features. Biomaterials offer benefits: control over the loading and release kinetics of multiple immune cargoes, and protection from enzymatic degradation and extreme pH. Moreover, biomaterials can be conjugated with antibodies or receptor ligands to contribute the molecular-specific target to immune cells or membrane proteins/genes. This feature can be exploited to reduce systemic and local toxicity.
Evolution
Published in Paul Pumpens, Single-Stranded RNA Phages, 2020
Ichihashi et al. (2013) constructed an evolvable artificial cell model from an assembly of biochemical molecules. The artificial cell model contained the artificial genomic RNA that replicated through the translation of the encoded Qβ replicase. A long-term replication experiment of 600 generations was performed. The mutations were spontaneously introduced into the RNA by replication error, and highly replicable mutants dominated the population according to the Darwinian principles. During evolution, the genomic RNA gradually reinforced its interaction with the translated replicase, thereby acquiring competitiveness against selfish parasitic RNAs. This study provided the first experimental evidence that replicating systems could be developed through the Darwinian evolution in a cell-like compartment, even in the presence of parasitic replicators. Then, Mizuuchi et al. (2014) tested the adaptive evolutionary ability of the artificial RNA genome replication system to a reduced-ribosome environment. It was observed that the mutant genome compensated for the reduced ribosome concentration by the introduction of several mutations around the ribosome-binding site in order to increase the translation efficiency.
Regeneration: Nanomaterials for Tissue Regeneration
Published in Harry F. Tibbals, Medical Nanotechnology and Nanomedicine, 2017
Yet another approach is the engineering of artificial organs, which may or may not include living encapsulated cells, but which are designed to function as an entire replacement for complex units such as the pancreas, liver, kidney, or even the heart or eye. The design of artificial organs and artificial cells or bioreactors may be considered as a development of the prosthetics or substitutional medicine paradigm from the mechanical and neuromuscular arena into the biochemical and cell-signaling domain.
The role of artificial cells in the fight against COVID-19: deliver vaccine, hemoperfusion removes toxic cytokines, nanobiotherapeutics lower free radicals and pCO2 and replenish blood supply
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2022
Artificial cells are attempts to mimic some of the properties of biological cells for use in medicine. This author prepared the first artificial cells by enclosing the content of red blood cells inside ultrathin polymer membranes of cellular dimensions (Figure 1) [3,4]. He then extended this research by going outside the box with variations in contents, membrane composition, and configurations (Figure 1). Contents of artificial cells include haemoglobin, enzymes, cells, vaccines, compartments, cytosol, organelles, magnetics, adsorbent, insulin and later, stem cells, gene, DNA, mRNA, silver, gold, miroorganisms, biotechnological products and others (Figure 1). Membrane composition include polymeric membrane, lipid membrane, biodegradable membrane, crosslinked protein membrane, conjugation, lipid-polymeric membrane, PEGalated membrane and others (Figure 1). It has since been developed around the world into many configurations and dimensions under different names for different specific applications (Figure 1) [2,5–19]. One can now taylor-made Artificial Cells to suit specific applications. It has now evolved into many different areas including blood substitutes, hemoperfusion, nanomedicine, nanobiotherapeutics, drug delivery, regenerative medicine, cell/stem cell encapsulation, nanoparticles, liposomes, bioencapsulation, and other areas. Artificial cell is now a very large area and reviews on artificial cells are available elsewhere [2,5,7]. Figure 1 is a summary of the area.
Design of artificial cells: artificial biochemical systems, their thermodynamics and kinetics properties
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Adamu Yunusa Ugya, Lin Pohan, Qifeng Wang, Kamel Meguellati
Artificial cells can be defined as simple, small entities made up of a few properties of natural cells [12]. Certain phenotypes and functions of natural cells are mimicked by well defined in vitro artificial systems. The various types of created artificial cells are protocells [13], where artificial cells were constructed using synthetic membranes and cellular components [14] and natural cell extracts such as essential genes and genetic circuits useful for their maintenance [15]. Artificial cells can be used to explore the dynamics of cell cycle regulation and to study the proliferation with minimal intervention. Second, to investigate the properties of biological cells, followed by the investigation of new applications and the expansion of biological regulations and mechanisms found in nature [16]. The essential properties and related structures of living cells should ideally be presented in typical artificial cells but can be expanded to more complexity [17]. A newly constructed artificial cell should possess three elementary features: a memory (DNA or RNA), a stable semi-permeable membrane, a series of metabolic pathways, and a complex epigenetic signal [18].
ARTIFICIAL CELL evolves into nanomedicine, biotherapeutics, blood substitutes, drug delivery, enzyme/gene therapy, cancer therapy, cell/stem cell therapy, nanoparticles, liposomes, bioencapsulation, replicating synthetic cells, cell encapsulation/scaffold, biosorbent/immunosorbent haemoperfusion/plasmapheresis, regenerative medicine, encapsulated microbe, nanobiotechnology, nanotechnology
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
In 1965 Bangham reports the use of microspheres of onion-like concentric multilamellar lipid bilayers as membrane models in basic research [43]. In 1968 Meuller and Rudin [44] reported that they use Chang’s method [2] to prepare single bilayer membrane vesicles. A McGill Ph.D. graduate, Gregoriadis, visits me before leaving for his postdoctoral fellowship in England. While there, he becomes the first person to start the use of liposomes as drug delivery systems [45]. However, onion-like multi-lamellar liposomes limits the loading of water-soluble drugs. Thus, in 1976 Deamer and Bangham [46] report the use of an “ether evaporation” method to form single bilayer lipid membrane vesicles. This “ether evaporation method” is an extension of the 1957 Chang method using ether for the preparation of artificial cells [1,2] (Figure 4). These lipid-membrane artificial cells have since been extensively studied and used as drug delivery systems around the world [47]. This is now a very successful approach for drug delivery. For the delivery of larger peptides, proteins and vaccines, the emphasis is using biodegradable polymeric system.