Decoupling Half-Process Assisted Mitochondrial Transplantation via Self-Stripping pHLIP Boosts Macrophages...

Exogenous mitochondrial transplantation holds promise for reprogramming macrophages with mitochondrial dysfunction to alleviate inflammation, yet its efficacy is hindered by poor targeting, low efficiency, or functional interference and cytotoxicity of modifiers. Herein, a convenient pH-low insertion peptides (pHLIPs)-tailored mitochondrial "decoupling transplantation" strategy (pHLIPs-PEG-TPP-Mito; PPT-Mito) is reported. In the first half, PPT-Mito can actively target the acidic cell surface of pro-inflammatory macrophages (M1) boosted by acid-sensitive pHLIPs. Subsequently, the PPT components spontaneously insert into the acidic cell membrane and self-stripped from PPT-Mito without additional intervention. This spatiotemporal separation of boosters from organelles facilitates "native" mitochondrial transplantation, while avoiding potential interference of boosters in the second half. This method significantly increases transplantation efficiency in M1 macrophages, as evidenced by a 230% increase compared to anti-inflammatory macrophages (M2)/PPT-Mito and 208% relative to M1/Mito. Consequently, PPT-Mito effectively promotes the reprogramming of M1 macrophages into M2 macrophages by remodeling energy metabolism and restoring mitochondrial function, ultimately inhibiting the inflammatory response both in vitro and in a model of periodontal inflammation. Overall, this study presents an ingenious and straightforward decoupling half-process-assisted strategy for mitochondrial transplantation, with broad potential for applications in the delivery of biological micro-organelles.