Effects of tumor derived exosomes on T cells markers expression / Efeitos de exossomos derivados de tumor na expressão de marcadores de células T

Exosomes are 30-120nm bio particles transferred from donor to recipient cells leading to modification in their regulatory mechanisms depending upon the coded message in the form of loaded biomolecule. Cancer cells derived exosomes the true representatives of the parent cells have been found to modify the tumor surrounding/distinct regions and participate in metastasis, angiogenesis and immune suppression. Tis study was aimed to study the effects of tumor mice derived exosomes on the normal mice spleen isolated T cells by using co-culture experiments and flow cytometer analysis. We mainly focused on some of the T cells population and cytokines including IFN-γ, FOXP3+ regulatory T (Treg) cells and KI67 (proliferation marker). Overall results indicated random changes in different set of experiments, where the cancer derived exosomes reduced the IFN-γ expression in both CD4 and CD8 T cells, similarly the Treg cells were also found decreased in the presence of cancer exosomes. No significant changes were observed on the Ki67 marker expression. Such studies are helpful in understanding the role of cancer exosomes in immune cells suppression in tumor microenvironment. Cancer exosomes will need to be validated in vivo and in vitro on a molecular scale in detail for clinical applications.

Os exossomos são biopartículas de 30-120 nm transferidas de células doadoras para células receptoras, levando à modificação em seus mecanismos reguladores, dependendo da mensagem codificada na forma de biomolécula carregada. Verificou-se que exossomos derivados de células cancerosas ­ os verdadeiros representantes das células-mãe ­ modificam as regiões circundantes / distintas do tumor e participam da metástase, angiogênese e imunossupressão. Este estudo teve como objetivo estudar os efeitos de exossomos derivados de camundongos com tumor nas células T isoladas de baço de camundongos normais, usando experimentos de cocultura e análise de citômetro de fluxo. Concentrou-se, principalmente, em algumas populações de células T e citocinas, incluindo IFN-γ, células T reguladoras FOXP3 + (Treg) e KI67 (marcador de proliferação). Os resultados gerais indicaram mudanças aleatórias em diferentes conjuntos de experimentos, em que os exossomos derivados de câncer reduziram a expressão de IFN-γ em células T CD4 e CD8, da mesma forma que as células Treg também foram encontradas diminuídas na presença de exossomos de câncer. Nenhuma mudança significativa foi observada na expressão do marcador Ki67. Esses dados são úteis para a compreensão do papel dos exossomos do câncer na supressão de células do sistema imunológico no microambiente tumoral. Exossomos de câncer precisarão ser validados in vivo e in vitro em escala molecular com detalhes para aplicações clínicas.

Exosomes and cystic echinococcosis: systematic review / Exosomas y equinococosis quística: revisión sistemática

SUMMARY: Exosomes are small and single-membrane secreted organelles, up to 200 nm in diameter that have the same topology as the cell, but are enriched in proteins, nucleic acids, lipids, and glycoconjugates. It can be found in any type of body fluids such as plasma, urine, saliva, sperm, bile, etc. On the other hand, cystic Echinococcosis (CE) has been studied from different points of view, among others, from genomics and proteomics, and the presence of CE exosomes in humans and other intermediate hosts has been reported in very few articles. The aim of this review was to report the evidence available regarding exosomes and CE. Systematic review. Data sources: Trip Database, SciELO, WoS, MEDLINE, EMBASE and SCOPUS. Eligibility criteria: Studies related to CEin any type of host and state of the parasite, without language restriction, published between 1966-2021. Variables: Year of publication, geographical origin, species isolated, location of exosomes. Forty-two studies were initially identified. After scrutinizing titles and abstracts, checking duplications and in-depth analysis of the studies selected, 12 articles including human, bovine, sheep, dog samples were also included. All were case reports or case series. The highest proportion of articles was published between 2019 and 2021 (58.3 %). Publications were predominantly from China (58.3 %). Evidence about exosomes and CE is scarce and reduced range of articles and cases.

RESUMEN: Los exosomas son orgánulos pequeños y secretados por una sola membrana, de hasta 200 nm de diámetro que tienen la misma topología que la célula, pero están enriquecidos en proteínas, ácidos nucleicos, lípidos y glicoconjugados. Se puede encontrar en cualquier tipo de fluidos corporales como plasma, orina, saliva, esperma, bilis, etc. Por otro lado, la equinococosis quística (CE) ha sido estudiada desde diferentes puntos de vista, entre otros, desde la genómica y proteómica, y la presencia de exosomas de CE en humanos y otros huéspedes intermediarios se ha informado en muy pocos artículos. El objetivo de esta revisión fue informar la evidencia disponible con respecto a los exosomas y la CE. Revisión sistemática. Fuentes de datos: Trip Database, SciELO, WoS, MEDLINE, EMBASE y SCOPUS. Criterios de elegibilidad: Estudios relacionados con la EC en cualquier tipo de hospedador y estado del parásito, sin restricción de idioma, publicados entre 1966-2021. Variables: año de publicación, origen geográfico, especie aislada, ubicación de exosomas. Se identificaron inicialmente 42 estudios. Después de examinar los títulos y resúmenes, verificar las duplicaciones y analizar en profundidad los estudios seleccionados, se incluyeron 12 artículos que incluían muestras de humanos, bovinos, ovinos y caninos. Todos fueron informes de casos o series de casos. La mayor proporción de artículos se publicó entre 2019 y 2021 (58,3 %). Las publicaciones fueron predominantemente de China (58,3 %). La evidencia sobre exosomas y CE es escasa y la gama de artículos y casos es reducida.

A 3D hydrogel loaded with exosomes derived from bone marrow stem cells promotes cartilage repair in rats by modulating immunological microenvironment / 南方医科大学学报

OBJECTIVE@#To assess the efficacy of GelMA hydrogel loaded with bone marrow stem cell-derived exosomes for repairing injured rat knee articular cartilage.@*METHODS@#The supernatant of cultured bone marrow stem cells was subjected to ultracentrifugation separate and extract the exosomes, which were characterized by transmission electron microscopy, particle size analysis and Western blotting of the surface markers. The changes in rheology and electron microscopic features of GelMA hydrogel were examined after loading the exosomes. We assessed exosome release from the hydrogel was detected by BCA protein detection method, and labeled the exosomes with PKH26 red fluorescent dye to observe their phagocytosis by RAW264.7 cells. The effects of the exosomes alone, unloaded hydrogel, and exosome-loaded hydrogel on the polarization of RAW264.7 cells were detected by q-PCR and immunofluorescence assay. We further tested the effect of the exosome-loaded hydrogel on cartilage repair in a Transwell co-culture cell model of RAW264.7 cells and chondrocytes in a rat model of knee cartilage injury using q-PCR and immunofluorescence assay and HE and Masson staining.@*RESULTS@#GelMA hydrogel loaded with exosomes significantly promoted M2-type polarization of RAW264.7 cells (P < 0.05). In the Transwell co-culture model, the exosome-loaded GelMA hydrogel significantly promoted the repair of injured chondrocytes by regulating RAW264.7 cell transformation from M1 to M2 (P < 0.05). HE and Masson staining showed that the exosome-loaded hydrogel obviously promoted cartilage repair in the rat models damage.@*CONCLUSION@#GelMA hydrogel loaded with bone marrow stem cell-derived exosomes can significantly promote the repair of cartilage damage in rats by improving the immune microenvironment.

Differential expression profile of miRNAs in amniotic fluid exosomes from fetuses with Down syndrome / 南方医科大学学报

OBJECTIVE@#To investigate the role of miRNAs in amniotic fluid exosomes in growth and development of fetuses with Down syndrome (DS).@*METHODS@#Amniotic fluid were collected from 20 fetuses with DS and 20 normal fetuses (control) to extract amniotic exosome miRNA. MicroRNA sequencing technique was used to identify the differentially expressed miRNAs between the two groups, for which gene ontology (GO) and pathway analysis was performed. Three differentially expressed miRNAs with the strongest correlation with DS phenotype were selected for qPCR verification. Dual luciferase reporter assay was used to verify the activity of let-7d-5p for targeted regulation of BACH1.@*RESULTS@#We identified 15 differentially expressed miRNAs in DS as compared with the control group, among which 7 miRNAs were up-regulated and 8 were down-regulated. Target gene prediction results showed that the differentially expressed miRNAs targeted 17 DS-related genes. GO analysis revealed that the main functions of the target genes involved protein binding, protein transport, ATP binding, transferase activity and synapses. Pathway analysis revealed that the functional pathways were closely related with the development of the nervous system. qPCR results showed that the expression levels of miR-140-3p and let-7d-5p were significantly lower in DS group than in the control group (P < 0.05), as was consistent with miRNA sequencing results; the expression level of miR-4512 was significantly higher in DS group than in control group (P < 0.05), which was contrary to miRNA sequencing results. The results of double luciferase reporter gene assay confirmed that let-7d-5p was capable of targeted regulation of BACH1 expression.@*CONCLUSION@#Let-7d-5p in amniotic fluid exosomes may promote oxidative stress events in the brain of fetuses with DS by regulating BACH1 expression.

Ferroptosis in laryngeal squamous cell carcinoma and its regulation by M2 macrophage-derived exosomes / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate ferroptosis in laryngeal squamous cell carcinoma (LSCC) and its regulation by M2 macrophage-derived exosomes. Methods: LSCC and adjacent noncancerous tissue samples were collected from 32 patients treated in the Department of Otorhinolaryngology, Head and Neck Surgery of the Second Affiliated Hospital of Harbin between September 2018 and April 2021, including 26 males and 6 females, aged 43-79 years. The expressions of ferroptosis marker glutathione peroxidase 4(GPX4) in LSCC and adjacent noncancerous tissues were detected by immunohistochemistry and reverse transcriptase-polymerase chain reaction(RT-PCR). The correlations between GPX4 expression and clinicopathological factors in LSCC were analyzed. Biological changes of TU212 cells after treated with ferroptosis-induced agent erastin were detected by transmission electron microscope, cell counting kit-8(CCK-8), clone test, reactive oxygen species(ROS), malondialdehyde(MDA), glutathione(GSH), JC-1, RT-PCR and western blot. Exosomes were isolated from the supernatant of M0/M2 macrophages (M0-exos/M2-exos) and co-incubated with erastin-treated TU212 cells to detect the change of ferroptosis in cells of each group. The data were analyzed by SPSS software of version19.0. Results: GPX4 expression in LSCC tissues was significantly higher than that in adjacent noncancerous tissues (2.04±0.65 vs. 0.99±0.09, F=30.36, P<0.001), and was closely related to T stage and clinical stage (Ⅰ-Ⅱvs.Ⅲ-Ⅳ: 1.75±0.39 vs. 2.18±0.71, F=2.25, P<0.05; T1-2 vs. T3-4: 1.71±0.42 vs. 2.20±0.69, F=2.06, P<0.05). In TU212 cells treated with erastin, mitochondrial crest became smaller, membrane density increased, proliferation rate decreased, intracellular ROS level increased, mitochondrial membrane potential depolarized, GSH content decreased, intracellular MDA level increased and expressions of GPX4 mRNA and protein decreased. Change of M0 into M2 macrophages was induced by IL-4 stimulation. When erastin-treated TU212 cells were incubated with M2-exos, cell proliferation was partially restored and GPX4 expression was enhanced, and also with the recoveries of levels of ROS, MDA and GSH (all P<0.05). Conclusions: Ferroptosis is one of the cell death ways of LSCC. M2-exos may inhibit ferroptosis of LSCC cells.

Research advances on exosomes derived from adipose-derived mesenchymal stem cells in promoting diabetic wound healing / 中华烧伤杂志

Impaired healing of diabetic wounds is mainly attributed to its pathological mechanism, and refractory diabetic wounds bring heavy burdens to patients and society. Exosomes derived from stem cells possess the similar ability as stem cells in promoting tissue regeneration and more clinical advantages and are gradually playing important roles in wound healing. In recent years, researches have shown that exosomes derived from adipose-derived mesenchymal stem cells (ADSC-EXOs) can promote the healing of diabetic wounds by participating in various processes of wound healing. This article reviews the pathological mechanism leading to impaired healing of diabetic wounds, the related mechanism and the application prospect of ADSC-EXOs in promoting diabetic wound healing.

Effects of exosomes from human adipose-derived mesenchymal stem cells on pulmonary vascular endothelial cells injury in septic mice and its mechanism / 中华烧伤杂志

Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on pulmonary vascular endothelial cells (PMVECs) injury in septic mice and its mechanism. Methods: The experimental research method was adopted. The primary ADSCs were isolated and cultured from the discarded fresh adipose tissue of 3 patients (female, 10-25 years old), who were admitted to the First Affiliated Hospital of Air Force Medical University undergoing abdominal surgery, and the cell morphology was observed by inverted phase contrast microscope on the 5th day. The expressions of CD29, CD34, CD44, CD45, CD73, and CD90 of ADSCs in the third passage were detected by flow cytometry. The third to the fifth passage of ADSCs were collected, and their exosomes from the cell supernatant were obtained by differential ultracentrifugation, and the shape, particle size, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and β-actin of exosomes were detected, respectively, by transmission electron microscopy, nano-particle tracking analysis and Western blotting. Twenty-four adult male BALB/c mice were adopted and were divided into normal control group, caecal ligation perforation (CLP) alone group, and CLP+ADSC-exosome group with each group of 8 according to random number table (the same grouping method below) and were treated accordingly. At 24 h after operation, tumor necrosis factor (TNF-α) and interleukin 1β (IL-1β) levels of mice serum were detected by enzyme-linked immunosorbent assay, and lung tissue morphology of mice was detected by hematoxylin-eosin and myeloperoxidase staining, and the expression of 8-hydroxy-deoxyguanosine (8-OHdG) of mouse lung cells was detected by immunofluorescence method. Primary PMVECs were obtained from 1-month-old C57 mice regardless gender by tissue block method. The expression of CD31 of PMVECs was detected by immunofluorescence and flow cytometry. The third passage of PMVECs was co-cultured with ADSCs derived exosomes for 12 h, and the phagocytosis of exosomes by PMVECs was detected by PKH26 kit. The third passage of PMVECs were adopted and were divided into blank control group, macrophage supernatant alone group, and macrophage supernatant+ADSC-exosome group, with 3 wells in each group, which were treated accordingly. After 24 h, the content of reactive oxygen species in cells was detected by flow cytometry, the expression of 8-OHdG in cells was detected by immunofluorescence, and Transwell assay was used to determine the permeability of cell monolayer. The number of samples in above were all 3. Data were statistically analyzed with one-way analysis of variance and least significant difference t test. Results: The primary ADSCs were isolated and cultured to day 5, growing densely in a spindle shape with a typical swirl-like. The percentages of CD29, CD44, CD73 and CD90 positive cells of ADSCs in the third passage were all >90%, and the percentages of CD34 and CD45 positive cells were <5%. Exosomes derived from ADSCs of the third to fifth passages showed a typical double-cavity disc-like structure with an average particle size of 103 nm, and the protein expressions of CD9, CD63 and TSG101 of exosomes were positive, while the protein expression of β-actin of exosomes was negative. At 24 h after operation, compared with those in normal control group, both the levels of TNF-α and IL-1β of mice serum in CLP alone group were significantly increased (with t values of 28.76 and 29.69, respectively, P<0.01); compared with those in CLP alone group, both the content of TNF-α and IL-1β of mice serum in CLP+ADSC-exosome group was significantly decreased (with t values of 9.90 and 4.76, respectively, P<0.05 or P<0.01). At 24 h after surgery, the pulmonary tissue structure of mice in normal control group was clear and complete without inflammatory cell infiltration; compared with those in normal control group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP alone group were more obvious; compared with those in CLP alone group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP+ADSC-exosome group were significantly reduced. At 24 h after operation, endothelial cells in lung tissues of mice in 3 groups showed positive expression of CD31; compared with that in normal control group, the fluorescence intensity of 8-OHdG positive cells of the lung tissues of mice in CLP alone group was significantly increased, and compared with that in CLP alone group, the fluorescence intensity of 8-OHdG positive cells in the lung tissues of mice in CLP+ADSC-exosome group was significantly decreased. The PMVECs in the 3rd passage showed CD31 positive expression by immunofluorescence, and the result of flow cytometry showed that CD31 positive cells accounted for 99.5%. At 12 h after co-culture, ADSC-derived exosomes were successfully phagocytose by PMVECs and entered its cytoplasm. At 12 h after culture of the third passage of PMVECs, compared with that in blank control group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant alone group was significantly increased (t=15.73, P<0.01); compared with that in macrophage supernatant alone group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant+ADSC-exosome group was significantly decreased (t=4.72, P<0.01). At 12 h after culture of the third passage of PMVECs, and the 8-OHdG positive fluorescence intensity of PMVECs in macrophage supernatant alone group was significantly increased; and compared with that in blank control group, the 8-OHdG positive fluorescence intensity of PMVECs in macrophage+ADSC-exosome supernatant group was between blank control group and macrophage supernatant alone group. At 12 h after culture of the third passage PMVECs, compared with that in blank control group, the permeability of PMVECs monolayer in macrophage supernatant alone group was significantly increased (t=6.34, P<0.01); compared with that in macrophage supernatant alone group, the permeability of PMVECs monolayer cells in macrophage supernatant+ADSC-exosome group was significantly decreased (t=2.93, P<0.05). Conclusions: Exosomes derived from ADSCs can ameliorate oxidative damage in mouse lung tissue, decrease the level of reactive oxygen species, 8-OHdG expression, and permeability of PMVECs induced by macrophage supernatant.

Effects of exosomes from human adipose-derived mesenchymal stem cells on inflammatory response of mouse RAW264.7 cells and wound healing of full-thickness skin defects in mice / 中华烧伤杂志

Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on inflammatory response of mouse RAW264.7 cells and wound healing of full-thickness skin defects in mice. Methods: The experimental research methods were adopted. The discarded adipose tissue was collected from 3 female patients (aged 10-25 years) who underwent abdominal surgery in the First Affiliated Hospital of Air Force Medical University. ADSCs were extracted from the adipose tissue by collagenase Ⅰ digestion and identified with flow cytometry. Exosomes were extracted from the human ADSCs by differential ultracentrifugation, the morphology of the exosomes was observed by transmission electron microscopy, the particle diameter of the exosomes was detected by nanoparticle tracking analyzer, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and β-actin were detected by Western blotting. The human ADSCs exosomes (ADSCs-Exos) and RAW264.7 cells were co-cultured for 12 h, and the uptake of RAW264.7 cells for human ADSCs-Exos was observed. The RAW264.7 cells were divided into phosphate buffer solution (PBS) group stimulated with PBS for suitable time, endotoxin/lipopolysaccharide (LPS) stimulation 2 h group, LPS stimulation 4 h group, LPS stimulation 6 h group, LPS stimulation 12 h group, and LPS stimulation 24 h group stimulated with LPS for corresponding time, with 3 wells in each group, and the mRNA expressions of interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), IL-6, and IL-10 were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) method. The RAW264.7 cells were divided into PBS group, LPS alone group, and LPS+ADSCs-Exos group, with 3 wells in each group, which were dealt correspondingly for the time screened out in the previous experiment, the mRNA expressions of IL-1β, TNF-α, IL-6, IL-10, trasforming growth factor β (TGF-β,) and vascular endothelial growth factor (VEGF) were detected by real time fluorescence quantitative RT-PCR method, and the protein expressions of inducible nitric oxide synthase (iNOS) and arginase 1 (Arg1) were detected by Western blotting. Twenty-four 8-week-old male BALB/c mice were divided into PBS group and ADSCs-Exos group according to the random number table, with 12 mice in each group, and a full-thickness skin defect wound with area of 1 cm×1 cm was inflicted on the back of each mouse. Immediately after injury, the wounds of mice in the two groups were dealt correspondingly. On post injury day (PID) 1, the concentration of IL-1β and TNF-α in serum were detected by enzyme-linked immunosorbent assay, and the mRNA expressions of IL-1β, TNF-α, and IL-6 were detected by real time fluorescence quantitative RT-PCR method. On PID 3, 6, 9, 12, and 15, the wound healing was observed and the wound non-healing rate was calculated. On PID 15, the defect length of skin accessory and collagen volume fraction (CVF) were detected by hematoxylin eosin staining and Masson staining, respectively, the CD31 expression and neovascularization were detected by immunohistochemistry, and the ratio of Ki67 positive cells, the ratio of iNOS and Arg1 double positive cells, and the ratio of iNOS positive cells to Arg1 positive cells and their fluorescence intensities were detected by immunofluorescence method. The number of samples in animal experiments was 6. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and independent sample t test. Results: At 12 h of culture, the cells exhibited a typical spindle shape, which were verified as ADSCs with flow cytometry. The exosomes with a vesicular structure and particle diameters of 29-178 nm, were positively expressed CD9, CD63, and TSG101 and negatively expressed β-actin. After 12 h of co-culture, the human ADSCs-Exos were endocytosed into the cytoplasm by RAW264.7 cells. The mRNA expressions of IL-1β, TNF-α, IL-6, and IL-10 of RAW264.7 cells in LPS stimulation 2 h group, LPS stimulation 4 h group, LPS stimulation 6 h group, LPS stimulation 12 h group, and LPS stimulation 24 h group were significantly higher than those in PBS group (with t) values of 39.10, 14.55, 28.80, 4.74, 48.80, 22.97, 13.25, 36.34, 23.12, 18.71, 29.19, 41.08, 11.68, 18.06, 8.54, 43.45, 62.31, 22.52, 21.51, and 37.13, respectively, P<0.01). The stimulation 12 h with significant expressions of all the inflammatory factors was selected as the time point in the following experiment. After stimulation of 12 h, the mRNA expressions of IL-1β, TNF-α, IL-6, and IL-10 of RAW264.7 cells in LPS alone group were significantly higher than those in PBS group (with t values of 44.20, 51.26, 14.71, and 8.54, respectively, P<0.01); the mRNA expressions of IL-1β, TNF-α, and IL-6 of RAW264.7 cells in LPS+ADSCs-Exos group were significantly lower than those in LPS alone group (with t values of 22.89, 25.51, and 8.03, respectively, P<0.01), while the mRNA expressions of IL-10, TGF-β, and VEGF were significantly higher than those in LPS alone group (with t values of 9.89, 13.12, and 7.14, respectively, P<0.01). After stimulation of 12 h, the protein expression of iNOS of RAW264.7 cells in LPS alone group was significantly higher than that in PBS group and LPS+ADSCs-Exos group, respectively (with t values of 11.20 and 5.06, respectively, P<0.05 or P<0.01), and the protein expression of Arg1 was significantly lower than that in LPS+ADSCs-Exos group (t=15.01, P<0.01). On PID 1, the serum concentrations of IL-1β and TNF-α and the mRNA expressions of IL-1β, TNF-α, and IL-6 in wound tissue of mice in ADSCs-Exos group were significantly those in lower than PBS group (with t values of 15.44, 12.24, 9.24, 7.12, and 10.62, respectively, P<0.01). On PID 3, 6, 9, 12, and 15 d, the wound non-healing rates of mice in ADSCs-Exos group were (73.2±4.1)%, (53.8±3.8)%, (42.1±5.1)%, (24.1±2.8)%, and 0, which were significantly lower than (82.5±3.8)%, (71.2±4.6)%, (52.9±4.1)%, (41.5±3.6)%, and (14.8±2.5)% in PBS group, respectively (with t values of 4.77, 8.93, 5.54, 7.63, and 7.59, respectively, P<0.01). On PID 15, the defect length of skin accessory in wounds of mice in PBS group was significantly longer than that in ADSCs-Exos group (t=9.50, P<0.01), and the CVF was significantly lower than that in ADSCs-Exos group (t=9.15, P<0.01). On PID 15, the CD31 expression and the number of new blood vessels (t=12.99, P<0.01), in wound tissue of mice in ADSCs-Exos group were significantly more than those in PBS group, and the ratio of Ki67 positive cells was significantly higher than that in PBS group (t=7.52, P<0.01). On PID 15, the ratio of iNOS and Arg1 double positive cells in wound tissue of mice in PBS group was (12.33±1.97)%, which was significantly higher than (1.78±0.29)% in ADSCs-Exos group (t=13.04, P<0.01), the ratio of iNOS positive cells and the fluorescence intensity of iNOS were obviously higher than those of ADSCs-Exos group, and the ratio of Arg1 positive cells and the fluorescence intensity of Arg1 were obviously lower than those of ADSCs-Exos group. Conclusions: The human ADSCs-Exos can alleviate inflammatory response of mouse RAW264.7 cells, decrease macrophage infiltration and secretion of the pro-inflammatory cytokines, increase the secretion of anti-inflammatory cytokines to promote neovascularization and cell proliferation in full-thickness skin defect wounds of mice, hence accelerating wound healing.

Effect of human decidua mesenchymal stem cells-derived exosomes on the function of high glucose-induced senescent human dermal fibroblasts and its possible mechanism / 中华烧伤杂志

Objective: To establish a high glucose senescent model of human dermal fibroblasts (HDFs), and to investigate the effects of exosomes derived from human decidua mesenchymal stem cells (dMSCs) on the proliferation, migration, and apoptosis of senescent HDFs and possible mechanism. Methods: The experimental research method was used. From January to March 2021, discarded foreskin tissue was collected for isolation and culture of primary HDFs from 4 male phimosis patients (aged 18-22 years) admitted for circumcision in the Fourth Medical Center of the PLA General Hospital. The 6th passage of HDFs were taken and divided into low glucose group and high glucose group according to the random number table, and subsequently cultured in low-glucose complete medium and high-glucose complete medium, respectively, with medium changed every 72 h without subculturing. After 10 days of culture, the cells were taken and measured for cellular senescence using the β-galactosidase kit at 24 h after seeding; the expression of senescence-related proteins p16 and p53 was assessed by Western blotting at 48 h after seeding; cell proliferation was detected at 24, 48, and 72 h after seeding using the cell counting kit 8 (CCK-8) method; the cell proliferation was evaluated by 5-ethynyl-2'-deoxyuridine (EdU) staining method, cell cycle and apoptosis were measured by flow cytometry after 48 h of seeding; Transwell experiment was used for the calculation of cell migration rate at 24 h after seeding. The human dMSCs were taken and cultured for 48-72 h from which the exosomes were extracted by differential high speed centrifugal method. The morphology of dMSC exosomes was observed by transmission electron microscopy, the particle size distribution of dMSC exosomes was measured by nanoparticle tracking analysis, and the expression of dMSC-exosomes marker proteins CD9 and tumor susceptibility gene101 (TSG101) were detected by Western blotting. The dMSC exosomes and high-glucose complete medium-induced senescent HDFs were co-cultured for 24 hours, then PKH67 kit was used to detect the uptake of exosomes by HDFs. High-glucose complete medium-induced senescent HDFs were taken and divided into high glucose alone group, high glucose+low concentration of exosomes group, and high glucose+high concentration of exosomes group according to the same method above. The high-glucose complete medium with equal volume of phosphate buffered saline, dMSC exosomes with final concentration of 50 μg/mL, and dMSC exosomes with final concentration of 100 μg/mL were added to the corresponding groups for conventional cell culture, respectively. After grouped, the cell proliferation, cell cycle and apoptosis as well as cell migration were detected by CCK-8 method and EdU staining method, flow cytometry, and Transwell experiment at the corresponding time points as before, respectively. Based on the previous results, high-glucose complete medium-induced senescent HDFs were taken and divided into high glucose alone group and high glucose+high concentration of exosomes group for the same treatment. After being grouped and cultured for 48 h, real-time fluorescent quantitative polymerase chain reaction was used to evaluate the mRNA expression of senescent-related microRNA (miR)-145-5p, miR-498, miR-503-5p, calcium/calmodulin dependent protein kinase 1D (CAMK1D), phosphates and tensin homologue deleted on chromosome ten (PTEN) gene, and Cyclin D1 in high glucose alone group and high glucose+high concentration of exosomes group. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, least significant difference t test, and independent sample t test. Results: At 24 h after seeding, the rate of β-galactosidase-positive staining of HDF in high glucose group was (38.4±4.2)%, which was significantly higher than (16.5±2.2)% of low glucose group (t=4.65, P<0.01). At 48 h after seeding, the expression levels of senescence-related proteins p16 and p53 both were significantly higher in HDFs of high glucose group than those in low glucose group (with t values of 11.85 and 3.02, respectively, P<0.05 or P<0.01). At 0, 24, 48, and 72 h after seeding, the cell proliferation viability of HDFs in high glucose group was all significantly lower than in low glucose group (with t values of 4.13, 9.90, and 15.12, respectively, P<0.01). At 48 h after seeding, the rate of EdU-positive staining of HDFs in high glucose group was obviously lower than that of low glucose group (t=3.83, P<0.05). At 48 h after seeding, the percentage of G2/M+S subpopulations in three subpopulations (G0/G1, S, and G2/M) of HDF cycle was significantly lower in high glucose group than that in low glucose group (t=8.74, P<0.01). At 24 h after seeding, the number of HDFs migrated through the filter membrane to the lower chamber was 37±6 in high glucose group, which was significantly less than 74±7 in low glucose group (t=8.42, P<0.01). At 48 h after seeding, the HDF apoptosis rate was significantly higher in high glucose group than in low glucose group (t=8.48, P<0.01). The dMSC exosomes were cup-shaped or round vesicles with well-defined edges and uniform size distribution. The size of dMSC exosomes was basically in the range of 80-200 nm. Exosomal markers including CD9 and TSG101 were positively presented on the dMSC exosomes. After being co-cultured for 24 hours, the dMSC exosomes were taken up intracellularly by HDFs and mainly distributed around the nucleus of HDFs. After being grouped and cultured for 24, 48, and 72 h, the HDF proliferation viabilities in high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group were both significantly higher than in high glucose alone group (with t values of 6.36, 6.10, 7.76, 8.92, 12.17, and 10.74, respectively, P<0.01), the HDF proliferation viability in high glucose+high concentration of exosomes group was significantly higher than in high glucose+low concentration of exosomes group (with t values of 7.92, 4.82, and 4.72, respectively, P<0.01). After being grouped and cultured for 48 h, the percentages of EdU-positive HDFs in high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group were both significantly higher than in high glucose alone group (with t values of 5.32 and 9.88, respectively, P<0.01), the percentage of EdU-positive HDFs in high glucose+high concentration of exosomes group was notably higher than in high glucose+low concentration of exosomes group (t=5.27, P<0.01). After being grouped and cultured for 48 h, the proportion of G0/G1 subpopulation in both high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group was distinctly lower (with t values of 3.81 and 4.31, respectively, P<0.05), while the proportion of G2/M+S subpopulation was markedly higher (with t values of 3.81, 4.31, respectively, P<0.05) than in high glucose alone group. After being grouped and cultured for 24 h, the number of HDFs migrated through the filter membrane in both high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group was significantly higher than in high glucose alone group (with t values of 10.14 and 13.39, respectively, P<0.01), the number of HDFs migrated through the filter membrane in high glucose+high concentration of exosomes group was significantly increased than in high glucose+low concentration of exosomes group (t=6.27, P<0.01). After being grouped and cultured for 48 h, the HDF apoptosis rates in high glucose+low concentration of exosomes group and high glucose+high concentration of exosomes group were both significantly lower than in high glucose alone group (with t values of 3.72 and 5.53, respectively, P<0.05 or P<0.01). After being grouped and cultured for 48 h, compared with those in high glucose alone group, the mRNA expression levels of miR-145-5p and miR-498 were both obviously higher (with t values of 13.03 and 8.90, respectively, P<0.01), while the mRNA expression level of miR-503-5p was significantly lower (t=3.85, P<0.05) in high glucose+high concentration of exosomes group. After being grouped and cultured for 48 h, compared with those in high glucose alone group, the mRNA expression levels of CAMK1D and PTEN gene were both significantly lower (with t values of 8.83 and 5.97, respectively, P<0.01), while the mRNA expression level of Cyclin D1 was significantly higher in high glucose+high concentration of exosomes group (t=4.03, P<0.05). Conclusions: The dMSC exosomes are capable of improving cell proliferation and migration, and inhibiting cell apoptosis of high-glucose senescent HDFs. This may be related to the mechanism by which the increased expressions of intracellular miR-145-5p and miR-498 inhibit the expression of CAMK1D and PTEN gene, and the decreased expression of miR-503-5p promote the expression of Cyclin D1.

Research advances in the treatment of liver failure with mesenchymal stem cell-derived exosomes / 中华肝脏病杂志

Liver failure is a serious clinical syndrome in which multiple pathogenic factors exceed the liver's self-repair capability, resulting massive hepatocellular necrosis, rapid disease progression and high mortality. Liver transplantation is the most effective method for the treatment of liver failure, but it has disadvantages, such as insufficient liver donor and high cost. The clinical efficacy of mesenchymal stem cells in liver failure have been validated, but its application has been limited to certain extent. Cell-free-based therapies, especially mesenchymal stem cell-derived exosomes, has become a research hotspot in recent years. This paper reviews the research advances in the treatment of liver failure with the use of mesenchymal stem cell-derived exosomes.

Effect of lipopolysaccharide-stimulated exosomes from human dental pulp stem cells combined with stromal cell-derived factor-1 on dental pulp regeneration / 中华口腔医学杂志

Objective: To investigate the effect of exosomes from mild-inflammation- stimulated human dental pulp stem cells (hDPSC) combined with stromal cell-derived factor-1 (SDF-1) on dental pulp regeneration in rats. Methods: Primary hDPSCs were isolated, cultured and then stimulated by using lipopolysaccharide (LPS). The exosomes from the hDPSCs with (L-EXO) or without (N-EXO) LPS were extracted by overspeed differential centrifugation and were identified by transmission electron microscopy and Western blotting. Forty SD rats, aged 6-8 weeks, were equally divided into S group (SDF-1 alone), L+S group (L-EXO combined with SDF-1), N+S group (N-EXO combined with SDF-1) and blank control group (no substance implanted into the root canal) by random number table method. Bilateral mandibular first molars were used as the experimental teeth to establish pulpless root canal models and different contents were implanted into the root canals according to the groups. All rats were over-anesthetized and sacrificed at the 30th day after content implantation. Bilateral mandibular tissues were taken for histological evaluation by means of HE, Masson and immunohistochemical stainings. Results: The HE staining showed new pulp-like tissue in the root canals of all three experimental groups. The amount of new tissues and the number of cells in the tissues were greatest in L+S group and least in S group. Masson staining showed that the mineralized tissue in L+S group was arranged longitudinally along the root canal wall and the collagen fibers were arranged in an orderly fashion, while those in N+S group showed an irregular and disordered distribution. Quantitative analysis of the area of neovascularization in each group showed that the density of vessels in the L+S group [(2.03±0.65)%] was significantly higher than that in the S group [(0.65±0.05)%] and the N+S group [(1.06±0.38)%] respectively (F=5.879, P<0.05). Immunohistochemical staining showed that the expression of CXC chemokine receptor 4 (CXCR4) was significantly lower in S and L+S groups than in N+S group, with a statistically significant difference (F=8.633, P<0.01). Conclusions: Exosomes secreted by hDPSCs combined with SDF-1 might increase the amount of new tissue in the root canal and the density of blood vessels in the tissue. L-EXO showed a stronger effect than N-EXO did. The combination of L-EXO with SDF-1 might result in more regular arrangement of mineralized tissue and collagen fibers in the regenerative tissues.

Effect of exosome derived from ovarian cancer cell on the differentiation of fibroblast / 中华肿瘤杂志

Objective: To study the effects of exosome secreted by ovarian cancer (OC) cell on the differentiation and metastasis of normal fibroblasts (NFs). Methods: NFs were collected from patients who underwent hysteromyoma resection in the Affiliated Hospital of Qingdao University from May to December 2019. Exosome was extracted from the culture supernatant of SKOV3 cells by using ultra-high-speed centrifugation. The NFs were co-cultured with condition medium (CM), exosome of SKOV3 (SKOV3-exo) and control medium. The expression levels of fibroblast activation protein (FAP) and α-smooth muscle actin (α-SMA) were detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot. The metastatic ability of NFs was detected by Transwell array. Results: Under the transmission electron microscope, the extracellular vesicles extracted from the culture supernatant of SKOV3 were 30-100 nm in diameter with cup holder-like bilayer membrane structure, and the protein expression levels of TSG101 and HSP27 in exosomes (1.00±0.05 and 1.12±0.13) were higher than those of ovarian cancer SKOV3 cells (0.22±0.21 and 0.36±0.14, respectively, P<0.05). PKH67 fluorescently labeled exosomes could be taken up by NFs. The expression levels of α-SMA and FAP mRNA in CM group(2.91±0.15 and 3.21±0.33)and SKOV3-exo group (3.50±0.21 and 4.63±0.24, respectively) were higher than that in blank group (1.00±0.06 and 1.00±0.13, P<0.05). The protein expression levels of α-SMA and FAP in CM group and SKOV3-exo group (0.89±0.11 and 1.25±0.09, 0.81±0.09 and 1.20±0.12) were higher than those in the blank group (0.12±0.31 and 0.11±0.19, respectively, P<0.05). The migrated numbers of cells in the CM group and SKOV3-exo group [(215.01±14.80) and (389.72±19.43), respectively] were higher than that in the blank group [(113.73±4.70), P<0.05]. Conclusion: The exosome secreted by SKOV3 cells can be taken up by NFs, which makes it to differentiate into cancer associated fibroblasts (CAFs) and significantly enhances its metastatic ability, indicating that OC cells may promote the transformation of normal ovarian mesenchymal fibroblasts to CAFs through exosome pathways, and then promote the development of ovarian cancer.

The Role of Platelet Exosomes in Atherogenic Thrombosis --Review / 中国实验血液学杂志

Exosomes are subtypes of extracellur vesicles containing a variety of cell-specific proteins, lipids and nucleic acids released during cell activation or apoptosis, and play the role of intercellur communication mediators in different physiological and pathological processes. With the development of research in recent years, the role of platelet-derived exosomes in cardiovascular diseases has attracted extensive attention. This paper reviews the role of platelet-derived exosomes in atherosclerotic thrombosis and the potential role of platelet-derived exosomes as biomarkers for the diagnosis and treatment of atherosclerotic thrombotic disease and the problems to be solved.

Effect and Mechanism of Cxcr4 Gene-Modified BMSC-Derived Exosomes on Aplastic Anemia / 中国实验血液学杂志

OBJECTIVE@#To explore the improvement effect of CXC chemokine receptor 4 (Cxcr4) gene-modified bone marrow mesenchymal stem cell (BMSC)-derived exosomes on aplastic anemia (AA), and make a preliminary exploration of the mechanism.@*METHODS@#Mouse BMSCs were isolated and cultured, then infected by recombinant lentivirus carrying Cxcr4 gene. The expression of green fluorescence was observed through fluorescence microscope, the expression of Cxcr4 mRNA was detected by real-time fluorescence quantitative PCR, and the BMSC-derived exosomes modified with Cxcr4 gene were extracted. Mouse models of AA were constructed, and control group, model group (AA), AA+BMSC group, AA+NC-BMSC group, AA+Cxcr4-BMSC group were set up. Except control group and model group, the other three groups of mice were injected 400 μl exosomes from different sources via the tail vein, after 2 weeks, the routine blood indices and the number of bone marrow nucleated cells were detected, the pathological changes of bone marrow were observed by HE staining, and the expression level of Treg cells was detected by flow cytometry.@*RESULTS@#Mouse BMSCs were successfully isolated, and BMSCs with high expression of Cxcr4 and their exosomes were obtained. Compared with the control group, the number of red blood cell (RBC), white blood cell (WBC), and platelet (PLT), the hemoglobin (Hb) content and proportion of Treg cells in the peripheral blood of mice in the model group significantly decreased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01). The proliferation level of nucleated cells was low, and the medullary cavity was filled with a large number of fat cells. Compared with the model group, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+BMSC group, AA+NC-BMSC group, and AA+Cxcr4-BMSC group significantly increased (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01), and pathological changes of bone marrow were improved. In addition, the number of RBC, WBC, PLT, the Hb content and proportion of Treg cells in the peripheral blood of mice in the AA+Cxcr4-BMSC group were significantly higher than those in the AA+BMSC group (P<0.01), as well as the number of bone marrow nucleated cells (P<0.01).@*CONCLUSION@#Injection of Cxcr4 gene-modified BMSC-derived exosomes has a certain improvement effect on AA mice, and the mechanism may be related to an increase of the proportion of Treg cells.

Biosensor-based assay of exosome biomarker for early diagnosis of cancer / 医学前沿

Cancer imposes a severe threat to people's health and lives, thus pressing a huge medical and economic burden on individuals and communities. Therefore, early diagnosis of cancer is indispensable in the timely prevention and effective treatment for patients. Exosome has recently become an attractive cancer biomarker in noninvasive early diagnosis because of the unique physiology and pathology functions, which reflects remarkable information regarding the cancer microenvironment, and plays an important role in the occurrence and evolution of cancer. Meanwhile, biosensors have gained great attention for the detection of exosomes due to their superior properties, such as convenient operation, real-time readout, high sensitivity, and remarkable specificity, suggesting promising biomedical applications in the early diagnosis of cancer. In this review, the latest advances of biosensors regarding the assay of exosomes were summarized, and the superiorities of exosomes as markers for the early diagnosis of cancer were evaluated. Moreover, the recent challenges and further opportunities of developing effective biosensors for the early diagnosis of cancer were discussed.

Research Progress of Mesenchymal Stem Cells and Their Exosomes on Tumors / 中国肺癌杂志

In China, malignant tumor is the main cause of death in both urban and rural areas. Mesenchymal stem cells (MSCs) have multidirectional differentiation potential, self-renewal ability and good immunomodulatory properties. Exosomes, as important paracrine substances of MSCs, mediate information exchange and transmission between cells in tumor microenvironment and influence the occurrence and development of tumors. Recently, conflicting findings have been reported on the effects of MSCs and their exosomes on tumors. On the one hand, MSCs and their exosomes are tumorigenic and can target specific sites to inhibit tumor growth; On the other hand, there is also evidence that MSCs could affect tumor growth and migration as part of the tumor microenvironment. In this paper, we will review the relationship between MSCs and exosomes and tumorgenesis and development, as well as how MSCs and exosomes play different roles in tumorgenesis and development, in order to provide beneficial help for tumor diagnosis, prognosis and precise treatment.
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Sequencing and Proteomic Analysis of Exosomes from Apheresis Platelets in Different Storage Periods / 中国实验血液学杂志

OBJECTIVE@#To investigate the changes of gene sequencing and proteomics of apheresis platelet (AP) exosomes in different storage periods and predict the function of AP exosomes in different storage periods.@*METHODS@#Platelets at different storage periods of 0 day (D0), 3 day (D3) and 5 day (D5) were collected, exosomes were extracted with Gradient centrifugation; gene sequencing and proteomic analysis were used to analyze the exosomes, and biological functions of platelet exosomes were analyzed and predicted by bioinformatics. Liquid mass spectrometry (LMS) was used to detect the changes and function prediction of exosomes proteins. The small RNA sequencing library was prepared, and the constructed library was sequenced and bioinformatics technology was used for data analysis.@*RESULTS@#AP exosome iTRAQ protein analysis showed that AP exosomes stored in D3 with 55 up-regulated proteins and 94 down-regulated proteins (P<0.05, FC<0.83 or FC>1.2), while AP exosomes stored in D5 with 292 up-regulated proteins and 53 down-regulated proteins (P<0.05, FC<0.83 or FC>1.2) as compared with D0. KEGG pathway analysis showed that the proteins were mainly involved in transport and metabolism, immune system, cancer, membrane transport and other processes. There were statistically significant differences between AP exosome miRNAs in different storage days (P<0.01). The number of miRNA up-regulated and down-regulated was 374 and 255 as compared with the number of platelet exosomes miRNA stored in D3 and D0, while that was 297 and 242 in D5 and D0, and 252 and 327 in D5 and D3, respectively. The target genes of differential platelet exosome miRNAs were analyzed by GO enrichment. Target genes of differential miRNA were mainly involved in membrane composition, mainly played molecular functions binding to proteins, and participated in biological processes of transcriptional regulation.@*CONCLUSION@#The exosome differential proteins and miRNAs in D5 are significantly different from those in the D0 of APs, and they are involved in various biological processes.

Proteomics of serum exosomes in children in the acute stage of Kawasaki disease: a prospective study / 中国当代儿科杂志

OBJECTIVES@#To study the biological processes and functions of serum exosomes in children in the acute stage of Kawasaki disease (KD), so as to provide new biomarkers for the early diagnosis of KD.@*METHODS@#In this prospective study, 13 children with KD who were treated in Children's Hospital of Soochow University from June 2019 to August 2020 were enrolled as the KD group, and 13 children who were hospitalized due to bacterial infection during the same period were enrolled as the control group. Whole blood was collected on the next morning after admission, serum samples were obtained by centrifugation, and exosomes were extracted through ultracentrifugation. Serum exosomes were analyzed by label-free quantitative proteomics, and differentially expressed proteins (DEPs) were screened out for functional enrichment analysis. A protein-protein interaction (PPI) network was plotted, and unique proteins were validated by targeted proteomics.@*RESULTS@#A total of 131 DEPs were screened out for the two groups, among which 27 proteins were detected in both groups. There were 48 unique DEPs in the KD group, among which 23 were upregulated and 25 were downregulated, and these proteins acted on "complement and coagulation cascades" and "the MAPK signaling pathway". Validation by targeted proteomics showed that FGG, SERPING1, C1R, C1QA, IGHG4, and C1QC proteins were quantifiable in the KD group. A total of 29 proteins were only expressed in the control group, among which 12 were upregulated and 17 were downregulated. Four proteins were quantifiable based on targeted proteomics, i.e., VWF, ECM1, F13A1, and TTR. A PPI network was plotted for each group. In the KD group, FGG and C1QC had close interaction with other proteins, while in the control group, VWF had close interaction with other proteins.@*CONCLUSIONS@#The serum exosomes FGG and C1QC in children in the acute stage of KD are expected to become the biomarkers for the early diagnosis of KD. For children with unexplained fever, detection of FGG, C1QC1, and VWF may help with etiological screening.

Application of RUNX2 gene over expression vector modified exosomes from BMSC combined with calcium carbonate scaffold system in bone defect / 中国骨伤

OBJECTIVE@#To investigate the effect of RUNX2 gene overexpression vector modified exosomes derived from bone marrow mesenchymal stem cells (BMSCs) combined with calcium carbonate scaffold system in bone defect.@*METHODS@#Rabbit BMSCs were used as the research object, and BMSCs were identified by flow cytometry. Construct RUNX2 gene overexpression vector, transfect BMSCs with lentivirus, and collect exosomes by ultracentrifugation. The morphology of exosomes was observed by transmission electron microscope, the expression of exosome marker CD63 was detected by Western blot, and the calcium carbonate scaffold was constructed by three chamber parallel automatic temperature control reaction system. According to whether the RUNX2 gene overexpression vector was transfected or not, the complex of BMSCs and calcium carbonate scaffold was divided into three groups, namely BMSCs group, RUNX2 overexpression group and exosome group. The osteogenic differentiation of BMSCs was detected by oil red O staining and RT-PCR. There were 9 clean adult healthy male New Zealand white rabbits, aged (12.97±1.21) months, with a body weight of (19.3±3.6) kg, with 3 rabbits in each group. The animal model of skull defect was constructed by surgical method, and the repair of bone defect was evaluated by imaging, he staining and Masson staining.@*RESULTS@#The results of flow cytometry showed that the expression of CD29 protein, CD44 protein, CD11b protein and CD45 protein on the surface of BMSCs were 99.5%, 100%, 0.1% and 0.1%, respectively. Transmission electron microscopy showed that the exosomes were bilayer vesicles with a diameter of 50 to 150 nm. Western blot showed that the molecular marker CD63 of exosomes was positive. Oil red O staining showed that the osteogenic differentiation of BMSCs in exosome group was significantly higher than that in RUNX2 overexpression group and BMSCs group. The results of RT-PCR showed that the relative expressions of RUNX2, BMP-2 and ALP mRNA in BMSCs in exosome group were significantly higher than those in RUNX2 overexpression group and BMSCs group (P<0.05). The imaging results showed that the repair effect of skull defect in exosome group was better than that in RUNX2 overexpression group. HE staining and Masson staining showed that the repair effect of skull defect in exosome group was better than that in RUNX2 overexpression group (P<0.05). MSCs in exosome group was significantly higher than that in RUNX2 overexpression group and BMSCs group. The results of RT-PCR showed that the relative expressions of RUNX2, BMP-2 and ALP mRNA in BMSCs in exosome group were significantly higher than those in RUNX2 overexpression group and BMSCs group(P<0.05). The imaging results showed that the repair effect of skull defect in exosome group was better than that in RUNX2 overexpression group. HE staining and Masson staining showed that the repair effect of skull defect in exosome group was better than that in RUNX2 overexpression group(P<0.05).@*CONCLUSION@#Compared with RUNX2 gene overexpression vector transfection, extraction of exosomes directly can promote the differentiation of BMSCs into osteoblasts more efficiently, and the combination with calcium carbonate scaffold can better promote the healing of bone defects. So as to provide new ideas and methods for the clinical treatment of bone defects.

Exosomes from PM 2.5-treated Human Bronchial Epithelial Cells Increase Lung Cancer Metastatic Potential / 生物医学与环境科学（英文）

Objective@#Fine particulate matter (PM 2.5) is an air pollutant that has become of great concern in recent years. Numerous studies have found that PM 2.5 may contribute to lung cancer, but the pathogenesis has not yet been fully elucidated. In this study, we explored the roles of exosomes from bronchial epithelial cells in PM 2.5-promoted lung cancer metastasis.@*Methods@#Exosomes were isolated from cell supernatants. An animal model of lung metastasis (established by tail vein injection of A549-luc) and in vitro studies with lung cancer cell lines were used to investigate the effects of exosomes derived from PM 2.5-treated human bronchial epithelial cells (PHBE-exo).@*Results@#The animal experiments revealed that PHBE-exo-treated mice showed stronger luciferase activity and a larger relative metastatic region in the lungs, thus indicating that PHBE-exo promoted the metastatic potential of lung cancer. Additionally, PHBE-exo promoted the migration, invasion and epithelial-to-mesenchymal transition of lung cancer cells, in a manner mediated by activation of c-Jun N-terminal kinase.@*Conclusion@#These results implied that PM 2.5 may promote the development of lung cancer through exosomes derived from bronchial epithelial cells, thus providing a potential interventional target for lung cancer. These findings broadened our understanding of cancer-promoting mechanisms of environmental pollutants.