Nanoparticles disguised as red blood cells to evade the immune system

Summary

This perspective reviews red-blood-cell membrane coating as an alternative to polyethylene glycol for extending nanoparticle circulation. Long residence in blood can increase opportunities for drug carriers to reach tumors through passive or active targeting. Conventional PEG coatings create a hydrated barrier that reduces uptake by the mononuclear phagocyte system. The biomimetic approach instead wraps a nanocarrier in natural erythrocyte membrane, presenting it as a form of biological “self.” The authors highlight evidence that such particles can circulate longer than corresponding PEGylated systems and discuss distinctive features and future prospects of the platform. The principal argument is that transferring an integrated natural membrane may reproduce multiple survival signals beyond the steric protection of one synthetic polymer. This is significant as a new design principle for long-circulating delivery. However, the article is an opinion-oriented review, and the abstract provides no quantitative half-lives, particle formulations, disease models, cargo efficacy, safety outcomes, or systematic comparison. Longer circulation does not guarantee tumor delivery or clinical benefit. Membrane sourcing, blood-group and donor variability, pathogen removal, storage, repeated-dose immunity, accelerated clearance, scale-up, quality control, and regulation remain major unresolved barriers.