Hypoxia severely limits the antitumor immunotherapy for breast cancer. Although efforts to alleviate tumor hypoxia and drug delivery using diverse nanostructures achieve promising results, the creation of a versatile controllable oxygen-releasing nano-platform for co-delivery with immunostimulatory molecules remains a persistent challenge. To address this problem, a versatile oxygen controllable releasing vehicle PFOB@F127@PDA (PFPNPs) is developed, which effectively co-delivered either protein drug lactate oxidase (LOX) or nucleic acids drug unmethylated cytosine-phosphate-guanine oligonucleotide (CpG ODNs). Upon photothermal heating, this platform triggered oxygen release, thereby augmenting LOX-mediated lactate detection rates, and improving T cells infiltrating and cytokine expression. Moreover, under an oxygenated tumor microenvironment (TME), PFPNPs co-delivered with CpG ODNs effectively reprogrammed the immunosuppressive TME by repolarizing macrophages to an M1-like phenotype, promoting dendritic cells maturation, and increasing tumor-infiltrating T cells while decreasing the ratio of regulatory T cells (Tregs). Our study demonstrated that this controlled oxygen-releasing platform possessed adaptive drug-loading capabilities to meet varied immunotherapeutic demands in clinical settings.
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