Bioinspired, Cytocompatible Mineralization of Silica–Titania Composites: Thermoprotective Nanoshell Formation for Individual Chlorella Cells

Abstract

Hard-shell case: Using a (RKK)4 D8 peptide allows mineralization to occur under cytocompatible conditions. Thus individual Chlorella cells could be encapsulated within a SiO2 -TiO2 nanoshell with high cell viability (87 %). The encapsulated Chlorella showed an almost threefold increase in their thermo-tolerance after 2 h at 45 °C.

Cytoprotective Encapsulation of Individual Jurkat T Cells within Durable TiO2 Shells for T‐Cell Therapy

“…After 2days at 40 8 8Ci naw ater bath, 75 %o f Jurkat@TiO 2 cells were alive,but the viability of native Jurkat cells sharply dropped to 35 %. Even after 6days,the viability of Jurkat@TiO 2 was still 23 %, but that of the native cells was only 5%.These results confirmed that Jurkat@TiO 2 acquired the enhanced long-term viability under ordinary-life condi-tions as well as the resistance to heat stress, [21] characteristics of artificial spores. [8a] Jurkat cells have aC D3 T-cell co-receptor on the cell surface,w hich plays an important role in the activation of T cells.W hent he CD3 receptor is stimulated, phosphorylation of immunoreceptor tyrosine-based activation motif (ITAM) is induced, and the signaling cascade for T-cell activation proceeds.…”

Metal–Organic Framework Coatings as Cytoprotective Exoskeletons for Living Cells

“…Recent studies have demonstrated that fabricating durable, synthetic coatings around living cells affords prolonged cellular viability to environmental stresses . To this end various protective coatings have been explored, including silica, silica‐titania, graphene, polydopamine, and an iron‐tannate coordination complex . Although these cell coatings offer a degree of protection from the external environment, controlled diffusion of molecules through the shell has not been demonstrated.…”

An Enzyme‐Coated Metal–Organic Framework Shell for Synthetically Adaptive Cell Survival

“…Recently,a rtificial nanocoatings have appeared as an approach to mimic the robustness of cell membranes and walls found in some extremophiles,while avoiding genetic modification. [7][8][9] Nanocoating cell surfaces creates ap hysical barrier between the cell and the external environment while still allowing nutrient exchange.T hese nanocoatings have improved cellular tolerance against heat, [10,11] UV radiation, [12,13] toxins, [14][15][16][17] osmotic pressure, [18,19] and mechanical stress. [20,21] Although nanocoatings have demonstrated protective abilities,t heir integration with active biomacromolecules is ac hallenge.T his prevents the bioengineering of such coatings with extrinsic bioactive functionalities that could impart artificial adaptive ability, thus overcoming original biological limitations.F or example, eukaryotic cells lack the ability to harvest energy from nutrient-depleted environments; [22] however, providing cells with abioactive protective nanocoating capable of converting depleted media into usable nutrients could furnish new opportunities in therapy, [23] diagnostics, [24] stressresponse, [25,26] and biocatalysis, [27] and could also revolutionize the dairy and pharmaceutical industries.…”