Transglutaminase-Catalyzed Encapsulation of Individual Mammalian Cells with Biocompatible and Cytoprotective Gelatin Nanoshells

Abstract

Mammalian cells are extremely vulnerable to external assaults compared with plant and microbial cells because of the weakness of cell membranes compared with cell walls. Construction of ultrathin and robust artificial shells on mammalian cells with biocompatible materials is a promising strategy for protecting single cells against harsh environmental conditions. Herein, layer-by-layer assembly combined with a transglutaminase-catalyzed cross-linking reaction was employed to prepare cross-linked and biocompatible gelatin nanoshells on individual human cervical carcinoma cell line (HeLa) cells and mouse insulinoma cell line 6 (MIN6) cells. The encapsulated HeLa and MIN6 cells showed high viability and a prolonged encapsulation period. Moreover, the nanoshells can protect encapsulated cells from cytotoxic enzymes (such as trypsin) and polycation (polyethylenimine) attacks and help cells resist high physical stress. We also investigated how nanoshells would affect the cell viability, proliferation, and cell cycle distribution of encapsulated and released cells. The approach presented here may provide a new and versatile method for nanoencapsulation of individual mammalian cells, which would help cells endure various environmental stresses and thereby expand the application field of isolated mammalian cells.

Synthesis and Characterization of Silk Ionomers for Layer-by-Layer Electrostatic Deposition on Individual Mammalian Cells

“…Nanoencapsulation of individual mammalian cells in thin and tough polymer shells has been proposed as a potential strategy to form artificial cell walls for protection against physical and chemical stresses and immune attacks applied during ex vivo and in vivo manipulation such as tissue engineering applications and cell therapy. , Several approaches, including binding of biopolymers to surface receptors, − matrix-ion complexation, , and in situ polymerization or cross-linking on a cell surface − have been demonstrated for the encapsulation of individual mammalian cells. The most common strategy, however, has been the electrostatic layer-by-layer (LbL) assembly of polyelectrolytes or minerals, ,− which is widely employed for the formation of nanoscale multilayer films on charged surfaces − or nanoencapsulation of bacteria, yeast, − or pancreatic islands. − The net negative charge of the plasma membrane allows for electrostatic aggregation of positively charged polyelectrolytes onto a cell surface, enabling deposition of a negatively charged polyelectrolyte as the second layer. By alternating incubation in aqueous solutions of oppositely charged substrates, it is possible to assemble nanoscale multilayers on cell surfaces, and the composition and thickness can easily be tuned by altering the type and number of the layers deposited. , …”

Cell-based biocomposite engineering directed by polymers

“…For instance, an acyl transfer reaction catalyzed by transglutaminase was employed to prepare crosslinked gelatin nanoshells on individual cells with high biocompatibility. 119…”

A Decade of Advances in Single‐Cell Nanocoating for Mammalian Cells

“…Polyelectrolytes can be generally divided into two types according to their origins: synthetic and natural polyelectrolytes ( Table 2 ). [ 44–64 ] The most commonly used synthetic polyelectrolytes are poly‐ l ‐lysine (PLL), poly‐ l ‐arginine (PLA), polydiallyldimethyl ammonium chloride (PDADMAC), and polystyrene sulfonate (PSS). For example, Fournier and co‐workers tested several polyelectrolyte pairs for the construction of polymeric nanocoats on MELN cells through LbL technique.…”

“…For example, aminated gelatin type A produces the relevant positive charge for LbL self‐assembly with gelatin type B. [ 42,53 ] Both amination and carboxylation also have been used to switch the charge of silk fibroin to positive and negative, respectively. [ 54 ] Chitosan (CH) is a positively charged natural polymer; however, it is not dissolved in the neutral buffer solution, and its fabrication of polyelectrolyte multilayers on the cell surface has been limited due to cytotoxicity.…”