Design Principles and Multifunctionality in Cell Encapsulation Systems for Tissue Regeneration

Abstract

Cell encapsulation systems are being increasingly applied as multifunctional strategies to regenerate tissues. Lessons afforded with encapsulation systems aiming to treat endocrine diseases seem to be highly valuable for the tissue engineering and regenerative medicine (TERM) systems of today, in which tissue regeneration and biomaterial integration are key components. Innumerous multifunctional systems for cell compartmentalization are being proposed to meet the specific needs required in the TERM field. Herein is reviewed the variable geometries proposed to produce cell encapsulation strategies toward tissue regeneration, including spherical and fiber-shaped systems, and other complex shapes and arrangements that better mimic the highly hierarchical organization of native tissues. The application of such principles in the TERM field brings new possibilities for the development of highly complex systems, which holds tremendous promise for tissue regeneration. The complex systems aim to recreate adequate environmental signals found in native tissue (in particular during the regenerative process) to control the cellular outcome, and conferring multifunctional properties, namely the incorporation of bioactive molecules and the ability to create smart and adaptative systems in response to different stimuli. The new multifunctional properties of such systems that are being employed to fulfill the requirements of the TERM field are also discussed.

Cell encapsulation in liquified compartments: Protocol optimization and challenges

“…Cell encapsulation is a very promising method for the treatment of different endocrine diseases, including diabetes, liver and kidney failure. There are also advantages in using this methodology in Tissue Engineering and Regenerative Medicine (TERM), including mediation of undesired acute immune responses, while offering a three-dimensional (3D) environment essential for anchorage dependent cells [1]. In the particular case of liquefied cell encapsulation systems, a possible strategy to build the encapsulation membrane is through the Layer-by-Layer (LbL) technique, which has been proposed to process materials for a variety of biomedical applications [2].…”

Single‐Cell Nanoencapsulation: From Passive to Active Shells

“…[ 53 ] The yolk–shell‐like structures would be especially beneficial to the nanoencapsulation of mammalian cells, because they are encased with fragile cell membranes and the nanometer‐sized materials could be internalized more easily than microbial cells. [ 54 ] This type of cellular hybrid structures is not limited to the single‐cellular structure but includes structures containing multicells or cellular aggregates, [ 55 ] which would provide artificial systems of cytospace. In the multicell nanoencapsulation, control over the number of encapsulated cells would be preferred, as suggested before, [ 1b,7,11a ] which may benefit from recent advances in microfluidics in this direction.…”

Geometrically Controlled Liquefied Capsules for Modular Tissue Engineering Strategies

“…[ 1,2 ] In modular TE approaches, cell‐laden hydrogels are being considerably explored as building blocks to create modular tissues with specific geometries and mechanical properties. [ 3,4 ] Hydrogels are attractive 3D cell supportive platforms due to their highly hydrated nature, resembling the tissue‐like compliance of the native ECM. [ 5 ] Cell‐laden modular units enable the spatial and temporal manipulation of the biomaterials microenvironment, while avoid the invasive procedures inherent to scaffolds implantation into a defect site.…”