Cellular shellization: Surface engineering gives cells an exterior

Abstract

Unlike eggs and diatoms, most single cells in nature do not have structured shells to provide extensive protection. It is a challenge to artificially confer shell structures on living cells to improve their inherent properties and functions. We discuss four different types of cellular shellizations: man-made hydrogels, sol-gels, polyelectrolytes, and mineral shells. We also explore potential applications, such as cell storage, protection, delivery, and therapy. We suggest that shellization could provide another means to regulate and functionalize cells. Specifically, the integration of living cells and non-living functional shells may be developed as a novel strategy to create "super" or intelligent cells. Unlike biological approaches, this material-based bio-interface regulation is inexpensive, effective, and convenient, opening up a novel avenue for cell-based technologies and practices.

Improving cell-based therapies by nanomodification

“…The polymer exterior formed via above strategies acts as a “soft shell”, which may significantly alter the properties of cell surface, but is not necessarily robust enough to fight against mechanical attacks, heat or radiant threats [43, 64–68]. It has been found that natural systems choose hard and tough shell structures [20, 21] to enhance their survivability under harsh conditions.…”

“…intense light and high temperature) over the native ones [43]. Compared to microorganisms that have supportive cell wall structure, mineral-coating on mammalian cell is challenging as the hard shell materials may directly interact with cell membrane to affect its fluidity, and readily destroy its structure, leading to undesired cell toxicity [43, 68]. Despite the difficulties, researchers have made sustained efforts to achieve this challengeable goal (mammalian cell mineralization).…”

Controlled synthesis of mesoporous nanostructured anatase TiO2on a genetically modified Escherichia coli surface for high reversible capacity and long-life lithium-ion batteries

“…Functional domains of silaffin and silicatein-a were selected to modify the E. coli surface by means of bacterial surface display technique under the function of ice nucleation protein (INP). 31,32 Ice nucleation protein (INP) is oen used for anchoring proteins of interest on cell surface. 24 It is oen used in biocatalytic nanomaterial synthesis including silica, titanium dioxide, gallium oxide, barium oxouorotitanate.…”

Chitosan‐Based Nanocoatings for Hypothermic Storage of Living Cells

“…There are various approaches to the encapsulation of living cells . They can be encapsulated in, for example, hydrogels, complex coacervation gels, sol–gel matrixes, or coated by thin films/capsules . For preparation of useful cell nanocoatings many conditions have to be fulfill, such as: material biocompatibility, membrane stability, permeability, proper pore size, just to name some of them.…”

“…[6] They can be encapsulated in, for example, hydrogels, [7,8] complex coacervation gels, solgel matrixes, or coated by thin films/capsules. [9] For preparation of useful cell nanocoatings many conditions have to be fulfill, such as: material biocompatibility, membrane stability, permeability, proper pore size, just to name some of them. One of the most promising approaches for that purpose seems to be electrostatically driven self-assembly of polymers known also as layer-bylayer (LbL) technique.…”