A Strategy for Regeneration of Three-Dimensional (3D) Microtissues in Microcapsules: Aerosol Atomization Technique
Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon in Tissue Engineering Strategies for Organ Regeneration, 2020
A microcapsule is a hollow particle with solid shell with a diameter ranging from a few to thousands of micrometers (Gasperini et al. 2014, Sun 1997). Hydrogel based microcapsules are semipermeable that could enable the passage of proteins, nutrients, drugs, and allow the diffusion of oxygen, nutrients, therapeutic products and wastes, while blocking the entry of antibodies and immunocytes (Paredes Juarez et al. 2014). In tissue transplantation, microcapsule functions as an immune-protection. The islet cells placed inside the tiny capsules created a physical barrier to protect the islets from the immune system as reported previously (Vaithilingam and Tuch 2011). Therefore, cell encapsulation in biocompatible and semipermeable biopolymeric membranes is an effective method to overcome rejection of the implanted organ (Rabanel et al. 2009).
Marine Biopolymers
Se-Kwon Kim in Marine Biochemistry, 2023
Islet cells is the kind of cell in the pancreas, including alpha cells and beta cells, the last one producing the insulin, a hormone for controlling the glucose in blood. In the type I diabetic patient, a kind of autoimmune disease, the immune system does not recognize the islet cells and kills them as foreign substances, which makes the body not produce insulin. With this disease, the patients must inject insulin every day, which is inconvenient. Therefore, islet cell transplantation is a promising therapy. However, this therapy needs the pancreas from at least two deceased donors. In this situation, the development of tissue engineering is very necessary (Matsumoto, 2010). In islet cell transplantation, the hydrogels are made from crosslinks of alginate and cation Ca2+ or Ba2+ by the extrusion or electrostatic spraying technique. The last one has the advantage of making the small size gel beads but requiring not a high viscosity of alginate solution. The alginate gel used in many studies of islet cell transplantation showed good compatibility, avoided the attack of lymphocytes, controlled the glucose in plasma just one day after transplantation, and increased the survivor time (Mallett & Korbutt, 2008). Beside finding the source of beta cells with high bioactive like the nature islet cell, the technique in cell encapsulation is developed, from microencapsulation to micro-capsule then nanoencapsulation with only one islet cell for one nanoencapsule. With the 3D bioprinting, the cell scaffolds can get the desired forms. The islet cell nanoencapsule revealed many advantage as enhance the exchange mass by high area/volume ratio, protect islet from the immune system better, can distribute the nanoencapsules to the target organ (Abadpour et al., 2021).
Restoration: Nanotechnology in Tissue Replacement and Prosthetics
Harry F. Tibbals in Medical Nanotechnology and Nanomedicine, 2017
Cell encapsulation devices have been developed as research vehicles for studying the release of growth factors, neurotransmitters, and other signaling molecules from cells [143]. Various types of nanotechnology-assisted bioencapsulations have been developed for uses in medicine, biotechnology, tissue regeneration, stem cell therapy, nanorobotics, and artificial cells [144]. Here, we see the convergence of drug delivery, tissue scaffolding, and MEMS microdevices. The boundaries between these types of medical nanotechnol-ogy have become somewhat arbitrary.
Tissue engineering approaches and generation of insulin-producing cells to treat type 1 diabetes
Published in Journal of Drug Targeting, 2023
Mozafar Khazaei, Fatemeh Khazaei, Elham Niromand, Elham Ghanbari
IPCs, produced from diverse stem cell sources, can be engrafted in vivo. Encapsulating these cells before the implant are promising strategy for treating T1D that avoids the usage of systemic immunosuppression. To protect the graft against allogenic reactions and/or autoantibodies, immune-isolation is required [119]. Cell encapsulation inside a biocompatible semipermeable membrane is commonly used to create this state. These encapsulation devices must also meet certain requirements. The permeability of such a membrane must permit unrestricted nutrients, small molecular and oxygen exchange, as well as excellent insulin kinetics in response to blood glucose variations. Furthermore, they should prevent the passage of high molecular weight complexes such as immune cells and cytokines [66].
An overview of current advancements in pancreatic islet transplantation into the omentum
Published in Islets, 2021
Kimia Damyar, Vesta Farahmand, David Whaley, Michael Alexander, Jonathan R. T. Lakey
In 1980, Lim and Sun23 first reported that single implantation of encapsulated islets into insulin-dependent diabetic rats restored glycemic control for almost three weeks post-transplant. Additionally, the encapsulated islet recipients had significantly lower blood glucose levels compared to rats that received non-encapsulated islets.23 Since then, advancements have been made to improve islet encapsulation procedures for insulin delivery and expand its clinical application. Encapsulation involves the coating of islets in a biocompatible semi-permeable hydrogel membrane, which can then be transplanted into diabetic patients.24 The semi-permeable membrane allows the passage of oxygen, glucose, insulin, and nutrients while preventing the attachment of the immune cells and antibodies to the graft, which can delay rejection.25 Overall, there are two approaches to cell encapsulation for immune isolation of islets. Microencapsulation involves the containment of individual or small groups of islets within a chemically stable microsphere. In contrast, macroencapsulation is the coating of a large mass of islets within a biocompatible planar or cylindrical scaffold.26,27 Currently, the transplantation of microencapsulated islets into the omentum has been investigated.
Cell-loaded carboxymethylcellulose microspheres sustain viability and proliferation of ATDC5 cells
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Yu Ke, Caikun Liu, Yanting Wang, Meng Xiao, Jiachen Fan, Pengcheng Fu, Shuhao Wang, Gang Wu
Cell encapsulation in semipermeable membranes has attracted much attention in the field of regenerative medicine, because it provides a feasible microenvironment for cells to respond to soluble factors, extracellular matrix mediated signals and cell-cell interaction [7–10]. It mimics the morphology and physiology of the cells in living tissues and organs better than two-dimensional cultures. A variety of three-dimensional cellular spheroids with controlled differentiation can be made via cell-encapsulation to investigate cell behavior and intercellular interactions [11,12]. Cell spheroids can decline the de-differentiation of some cell lines, such as hepatocytes, to enhance liver-specific functions because of the extensive cell-cell contacts and tight junctions to mimic the morphology and ultrastructure of native liver lobule [13,14].
Related Knowledge Centers
- Antibody
- Diffusion
- Growth Factor
- Immunosuppressive Drug
- Semipermeable Membrane
- Metabolism
- Transplant Rejection
- Micro-Encapsulation
- Immobilized Whole Cell
- Therapeutic Effect