Targeted delivery of clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR‐associated protein 9 (Cas9) system to the receptor cells is essential for in vivo gene editing. Exosomes are intensively studied as a promising targeted drug delivery carrier recently, while limited by their low efficiency in encapsulating of large nucleic acids. Here, a kind of hybrid exosomes with liposomes is developed via simple incubation. Different from the original exosomes, the resultant hybrid nanoparticles efficiently encapsulate large plasmids, including the CRISPR–Cas9 expression vectors, similarly as the liposomes. Moreover, the resultant hybrid nanoparticles can be endocytosed by and express the encapsulated genes in the mesenchymal stem cells (MSCs), which cannot be transfected by the liposome alone. Taken together, the exosome–liposome hybrid nanoparticles can deliver CRISPR–Cas9 system in MSCs and thus be promising in in vivo gene manipulation.

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Biomaterials as bone substitutes are always considered as foreign bodies that can trigger host immune responses. Traditional designing principles have been always aimed at minimizing the immune reactions by fabricating inert biomaterials. However, clinical evidence revealed that those methods still have limitations and many of which were only feasible in the laboratory. Currently, osteoimmunology, the very pioneering concept is drawing more and more attention—it does not simply regard the immune response as an obstacle during bone healing but emphasizes the intimate relationship of the immune and skeletal system, which includes diverse cells, cytokines, and signaling pathways. Properties of biomaterials like topography, wettability, surface charge, the release of cytokines, mediators, ions and other bioactive molecules can impose effects on immune responses to interfere with the skeletal system. Based on the bone formation mechanisms, the designing methods of the biomaterials change from immune evasive to immune reprogramming. Here, we discuss the osteoimmunomodulatory effects of the new modification strategies—adjusting properties of bone biomaterials to induce a favorable osteoimmune environment. Such strategies showed potential to benefit the development of bone materials and lay a solid foundation for the future clinical application.