A combined "eat me/don't eat me" strategy based on exosome for acute liver injury treatment

Drug-induced liver injury (DILI) involves multifaceted pathogenesis, necessitating effective therapeutic strategies. Wnt2, secreted by liver sinusoidal endothelial cell (LSEC), activates the Wnt/β-catenin signaling pathway to promote hepatocyte proliferation after injury. To address the dual challenges of targeted delivery and phagocytosis evasion, we develop a combined "eat me/don't eat me" strategy. RLTRKRGLK (RLTR) peptide-functionalized exosomes are engineered by inserting DMPE-PEG2000-CRLTRKRGLK into the lipid membrane of exosome derived from bEnd.3 cell. Surface-displayed RLTR mediates exosomal enrichment in LSEC, while CD47 engineering reduces macrophage clearance via "don't eat me" signaling. Then, lentiviral transfection enables stable encapsulation of functional Wnt2 mRNA into Exo(CD47) (designated Wnt2@Exo(CD47)). In both acetaminophen (APAP) and dimethylnitrosamine (DMN)-induced murine liver injury models, RLTR-Wnt2@Exo(CD47) demonstrates LSEC-specific targeting and significant hepatoprotection. This engineered exosome platform provides a therapeutic strategy for DILI.