Aim

Polymeric nanoparticles (NPs) cloaked by red blood cell membrane (RBCm) confer the combined advantage of both long circulation lifetime and controlled drug release. The authors carried out studies to gain a better understanding of the drug loading, drug-release kinetics and cell-based efficacy of RBCm-cloaked NPs.

Materials & methods

Two strategies for loading doxorubicin into the RBCm-cloaked NPs were compared: physical encapsulation and chemical conjugation. In vitro efficacy was examined using the acute myeloid leukemia cell line, Kasumi-1.

Results

It was found that the chemical conjugation strategy resulted in a more sustained drug release profile, and that the RBCm cloak provided a barrier, retarding the outward diffusion of encapsulated drug molecules. It was also demonstrated that RBCm-cloaked NPs exhibit higher toxicity in comparison with free doxorubicin.

Conclusion

These results indicate that the RBCm-cloaked NPs hold great promise to become a valuable drug-delivery platform for the treatment of various diseases such as blood cancers.

RBC membrane-cloaked polymeric nanoparticles represent an emerging nanocarrier platform with extended circulation in vivo. A lipid-insertion method is employed to functionalize these nanoparticles without the need for direct chemical conjugation. Insertion of both folate and the nucleolin-targeting aptamer AS1411 shows receptor-specific targeting against model cancer cell lines.

Natural and artificial cells are two common chassis in synthetic biology. Natural cells can perform complex tasks through synthetic genetic constructs, but their autonomous replication often causes safety concerns for biomedical applications. In contrast, artificial cells based on nonreplicating materials, albeit possessing reduced biochemical complexity, provide more defined and controllable functions. Here, for the first time, the authors create hybrid material-cell entities termed Cyborg Cells. To create Cyborg Cells, a synthetic polymer network is assembled inside each bacterium, rendering them incapable of dividing. Cyborg Cells preserve essential functions, including cellular metabolism, motility, protein synthesis, and compatibility with genetic circuits. Cyborg Cells also acquire new abilities to resist stressors that otherwise kill natural cells. Finally, the authors demonstrate the therapeutic potential by showing invasion into cancer cells. This work establishes a new paradigm in cellular bioengineering by exploiting a combination of intracellular man-made polymers and their interaction with the protein networks of living cells.