| 1 | Exosomal PD-L1 induces osteogenic differentiation and promotes fracture healing by acting as an immunosuppressant显示文摘A moderate inflammatory response at the early stages of fracture healing is necessary for callus formation.Over-active and continuous inflammation,however,impairs fracture healing and leads to excessive tissue damage.Adequate fracture healing could be promoted through suppression of local over-active immune cells in the fracture site.In the present study,we achieved an enriched concentration of PD-L1 from exosomes(Exos)of a genetically engineered Human Umbilical Vein Endothelial Cell(HUVECs),and demonstrated that exosomes overexpressing PD-L1 specifically bind to PD-1 on the T cell surface,suppressing the activation of T cells.Furthermore,exosomal PD-L1 induced Mesenchymal Stem Cells(MSCs)towards osteogenic differentiation when pre-cultured with T cells.Moreover,embedding of Exos into an injectable hydrogel allowed Exos delivery to the surrounding microenvironment in a time-released manner.Additionally,exosomal PD-L1,embedded in a hydrogel,markedly promoted callus formation and fracture healing in a murine model at the early over-active inflammation phase.Importantly,our results suggested that activation of T cells in the peripheral lymphatic tissues was inhibited after local administration of PD-L1-enriched Exos to the fracture sites,while T cells in distant immune organs such as the spleen were not affected.In summary,this study provides the first example of using PD-L1-enriched Exos for bone fracture repair,and highlights the potential of Hydrogel@Exos systems for bone fracture therapy through immune inhibitory effects. | Ze Lin Yuan Xiong Weilin Meng Yiqiang Hu Lili Chen Lang Chen Hang Xue Adriana CPanayi Wu Zhou Yun Sun Faqi Cao Guodong Liu Liangcong Hu Chenchen Yan Xudong Xie Chuanchuan Lin Kaiyong Cai Qian Feng Bobin Mi Guohui Liu | 2022 | Bioactive Materials2022，7，7： | 4 |
| 2 | Glucose-responsive,antioxidative HA-PBA-FA/EN106 hydrogel enhanced diabetic wound healing through modulation of FEM1b-FNIP1 axis and promoting angiogenesis显示文摘The diabetic wounds remain to be unsettled clinically,with chronic wounds characterized by drug-resistant bacterial infections,compromised angiogenesis and oxidative damage to the microenvironment.To ameliorate oxidative stress and applying antioxidant treatment in the wound site,we explore the function of folliculininteracting protein 1(FNIP1),a mitochondrial gatekeeper protein works to alter mitochondrial morphology,reduce oxidative phosphorylation and protect cells from unwarranted ROS accumulation.And our in vitro experiments showed the effects of FNIP1 in ameliorating oxidative stress and rescued impaired angiogenesis of HUVECs in high glucose environment.To realize the drug delivery and local regulation of FNIP1 in diabetic wound sites,a novel designed glucose-responsive HA-PBA-FA/EN106 hydrogel is introduced for improving diabetic wound healing.Due to the dynamic phenylboronate ester structure with a phenylboronic acid group between hyaluronic acid(HA)and phenylboronic acid(PBA),the hydrogel is able to realize a glucose-responsive release of drugs.Fulvic acid(FA)is added in the hydrogel,which not only severs as crosslinking agent but also provides antibacterial and anti-inflammatory abilities.Moreover,the release of FEM1b-FNIP1 axis inhibitor EN106 ameliorated oxidative stress and stimulated angiogenesis through FEM1b-FNIP1 axis regulation.These in vivo and in vitro results demonstrated that accelerated diabetic wounds repair with the use of the HA-PBA-FA/EN106 hydrogel,which may provide a promising strategy for chronic diabetic wound repair. | Wenqian Zhang Kangkang Zha Yuan Xiong Weixian Hu Lang Chen Ze Lin Chenyan Yu Wu Zhou Faqi Cao Hankun Hu Bobin Mi Guohui Liu | 2023 | Bioactive Materials2023，，12： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员