Existing therapeutics for autoimmune diseases remain problematic due to low efficacy, severe side effects, and difficulties to reach target tissues. Herein, we design multifunctional fusion nanovesicles that can target lesions for the treatment of autoimmune skin diseases. The grapefruit‐derived exosome‐like nanovesicles (GEVs) with anti‐inflammatory and antioxidant effects are first encapsulated with CX5461, an immunosuppressant with anti‐proliferative properties to form GEV@CX5461. In order to enhance therapeutic efficiency and safety, GEV@CX5461 are then fused with CCR6+ nanovesicles derived from membranes of engineered gingiva‐derived mesenchymal stem cells (GMSCs). The resulting FV@CX5461 not only maintain the bioactivity of GEVs, CX5461, and GMSC membranes but also home to inflamed tissues rich in chemokine CCL20 through the chemotaxis function of CCR6 on FVs. Moreover, FV@CX5461 reduce the secretion of inflammatory factors, calm down Th17 cell activation, and induce Treg cell infiltration. Finally, impressive therapeutic efficiency in both psoriasis and atopic dermatitis disease models is demonstrated using FV@CX5461 to reshape the unbalanced immune microenvironment. A nanotherapeutic drug delivery strategy is developed using fusion nanovesicles derived from plant and animal cells with high clinical potential.

Excessive and persistent inflammation after injury lead to chronic wounds, increased tissue damage or even aggressive carcinogenic transformation. Effective wound repair could be achieved by inhibiting overactive immune cells to the injured site. In this study, we obtained high concentration of PD‐L1 in exosomes from either genetically engineered cells overexpressing PD‐L1 or IFN‐γ stimulated cells. We found that exosomal PD‐L1 is specially bound to PD‐1 on T cell surface, and suppressed T cell activation. Interestingly, exosomal PD‐L1 promoted the migration of epidermal cells and dermal fibroblasts when pre‐incubated with T cells. We further embedded exosomes into thermoresponsive PF‐127 hydrogel, which was gelatinized at body temperature to release exosomes to the surroundings in a sustained manner. Of importance, in a mouse skin excisional wound model, exosomal PD‐L1 significantly fastened wound contraction and reepithelialization when embedded in hydrogel during inflammation phase. Finally, exosomal PD‐L1 inhibited cytokine production of CD8+ T cells and suppressed CD8+ T cell numbers in spleen and peripheral lymph nodes. Taken together, these data provide evidence on exosomal PD‐L1 exerting immune inhibitory effects and promoting tissue repair.

The development of multifunctional nano drug delivery carriers has been one of the most effective and prevailing approaches to overcome drug non-selectivity, low cell uptake efficiency and various side effects of traditional chemotherapy drugs. Herein, we report a novel doxorubicin (DOX)-loaded mesoporous silica nanoparticle (MSN) coated with polydopamine (PDA) and polyethylene glycol (PEG) (MSNs-DOX@PDA-PEG) for the treatment of breast cancer. In this system, PDA functions as a pH-sensitive gatekeeper to control the release of DOX from MSNs in response to pH-stimulus and PEG was further grafted on the surface of PDA to increase the stability and biocompatibility under physiological conditions. The in vitro release results suggested that MSNs-DOX@PDA-PEG exhibits a high sensitivity to low pH. A cellular uptake assay showed a high cellular uptake efficiency of MSNs-DOX@PDA-PEG compared to free DOX. Furthermore, MSNs-DOX@PDA-PEG also demonstrated an improved anti-cancer efficacy compared to free DOX both in vivo and vitro breast cancer experiments. Mechanistic studies revealed that MSNs-DOX@PDA-PEG causes a stronger pro-death autophagy compared to free DOX via inhibition of the AKT-mTOR-p70S6K signaling pathway. Taken in concert, our results suggest that the novel material MSNs-DOX@PDA-PEG may represent a promising nanoformulation for breast cancer treatment.