Abstract

Impaired type I interferons (IFNs) may cause immune deficiency in tumours. Current supplementary IFN therapy partially restores anticancer immunity but simultaneously induces immune evasion by upregulating multiple immune checkpoints. Here we create a T lymphocyte membrane-decorated epigenetic nanoinducer that is engineered with programmed cell death protein 1 (PD1), which we call OPEN, for the delivery of the IFN inducer ORY-1001. OPEN increases IFNs and blocks IFN-induced immune checkpoint upregulation. OPEN also targets tumours that express programmed cell death ligand 1 (PDL1) through PDL1/PD1 recognition and subsequently triggers the internalization of OPEN and immune checkpoint proteins. OPEN, which is loaded with ORY-1001, upregulates intratumoural IFNs and downstream major histocompatibility complex I and PDL1. The replenished PDL1 enables further ligation of OPEN, which in turn blocks PDL1. These sequential processes result in an eight- and 29-fold increase of the intratumoural densities of total and active cytotoxic T lymphocytes, respectively, and a strong inhibition of xenograft tumour growth. This T lymphocyte membrane-decorated epigenetic nanoinducer presents a generalizable platform to boost antitumour immunity.