MACROPHAGE MEMBRANE-COATED NANOPARTICLES DELIVERING ANTAGOMIR OF MIR-155-5P MITIGATED TITANIUM PARTICLE-INDUCED OSTEOLYSIS BY MODULATING PERIPROSTHETIC MICROENVIRONMENT VIA GAS6/AXL SIGNALLING

Total joint replacement represents the primary therapeutic approach for end-stage arthropathy, whereas aseptic loosening stands as the predominant cause of prosthesis failure. Particle disease, a cause of aseptic loosening, delineates a phenomenon wherein wear particles derived from the implant initiate a series of biological events, including inflammatory responses in macrophages, osteoclastogenesis, and suppression of osteoblastogenesis, ultimately resulting in periprosthetic osteolysis. Macrophage biomimetic nanoparticles offered promising platform for drug controlled-release with preeminent bio-compatibility. This research investigated the specific mechanism that miR-155-5p/Gas6/Axl axis regulated pro-inflammatory cytokines production and osteoblastic function and provided a novel therapeutic scheme which nanoparticles were coated with macrophage membrane and loaded with antagomir of miR-155-5p for aseptic loosening. mRNA-seq and miRNA-seq were conducted for gene enrichment and key gene selection. In vitro, RAW264.7 and MC3T3-E1 cells were cultured or co-cultured for titanium particles'(TiPs) stimulation. ELISA, western blot and flow cytometry were utilized for detection of inflammatory response. Osteoblastic function was measured by ALP and ARS staining. In vivo, mice calvaria osteolytic model were constructed for simulation of particle disease, microCT scanning and IHC staining of mice calviaria section were applied. The PLGA-PEI complex was constructed and antagomir were loaded. And the encapsulated nanoparticles were co-extruded with macrophage membrane to constructed intact biomimetic nanoparticle (Anta-155@MNP). In TiPs-stimulated macrophages, Axl expression was upregulated, and Gas6 was released extracellularly. This signaling cascade played a crucial role in instigating the inflammatory response, including activation of the NF-κB pathway and JAK-STAT pathway. The binding of miR-155-5p to the 3'UTR of Mafb and Adam10 mRNAs indirectly regulated the transcription of Gas6 and the shedding of Axl, leading to the generation of a soluble form of Axl that facilitated osteoblastogenesis. In vivo, the osteolytic model induced by TiPs further corroborated that the miR-155-5p/Axl signaling axis promoted sterile inflammation while concurrently suppressing osteoblastic differentiation. We prepared Anta-155@MNP and it displayed remarkable anti-osteolytic property by neutralizing cytokines, reducing inflammatory response and provoking osteoblastogenesis. Meanwhile, Anta-155@MNP alleviated TiPs-induced osteolysis and tissue inflammation in vivo. The miR-155-5p/Gas6/Axl axis plays a crucial role in the regulation of the osteolytic microenvironment. Anta-155@MNP holds promise as a targeted therapy for aseptic loosening with potential for translation into clinical applications.