Immunotherapy of tumors by tailored nano-zeolitic imidazolate framework protected biopharmaceuticals
In cancer immunotherapy, antibodies have acquired rapidly increasing attention due to their sustained immune effect by target specific delivery without any adverse effects. Among many recent strategies, controlled delivery of monoclonal antibodies, check point inhibitor storage and tumor-specific targeted delivery have enabled biodegradable immunotherapeutic delivery via translation of tailored nano-zeolitic imidazolate frameworks (ZIFs) with encapsulated biopharmaceuticals. In addition, a robust antitumor immunity was developed by anti-programmed death ligand-1 (anti-PD-L1) antibody delivery by ZIF-8 with polyethylene glycol (PEG) protection by forming a multiple immunoregulatory system. The unique biorecognition capability of antibodies, encapsulated in ZIFs, was recognized by using growth on different substrates, such as bioconjugates on gold nanorods, to transform them into plasmonic nanobiosensors with sensitivity of the refractive index profile of surface plasmons to track the conjugating antibody. Herein, we have discussed the mechanistic window of antibody delivery-based immunotherapy via the encapsulation of antibodies within ZIFs as an emerging tool for protecting biopharmaceuticals from the complex cellular microenvironment and hyperthermia to enable an antitumor immune response. To fully achieve the potential of antibodies upon ZIF encapsulation, more endeavors should be undertaken in the biodegradable engineering of ZIF-surfaces via forming cellular or polymeric layers to gain higher in vivo circulation time without inhibiting endocytosis by tumor cells. The possible future prognosis for achieving ZIF-protected biocompatible and biodegradable immunotherapeutic antibody delivery systems of therapeutic significance is discussed.