Human Platelet-Rich Plasma-Derived Exosomes Promote the Proliferation of Schwann Cells Cultured in Vitro / 中国医学科学院学报

Objective To investigate the effect of human platelet-rich plasma-derived exosomes(PRP-exos)on the proliferation of Schwann cell(SC)cultured in vitro. Methods PRP-exos were extracted by polymerization-precipitation combined with ultracentrifugation.The morphology of PRP-exos was observed by transmission electron microscopy,and the concentration and particle size distribution of PRP-exos were determined by nanoparticle tracking analysis.Western blotting was employed to determine the expression of the marker proteins CD63,CD81,and CD9 on exosome surface and the platelet membrane glycoprotein CD41.The SCs of rats were isolated and cultured,and the expression of the SC marker S100β was detected by immunofluorescence staining.The fluorescently labeled PRP-exos were co-cultured with SCs in vitro for observation of their interaction.EdU assay was employed to detect the effect of PRP-exos on SC proliferation,and CCK-8 assay to detect the effects of PRP-exos at different concentrations(0,10,20,40,80,and 160 μg/ml)on SC proliferation. Results The extracted PRP-exos appeared as uniform saucer-shaped vesicles with the average particle size of(122.8±38.7)nm and the concentration of 3.5×1012 particles/ml.CD63,CD81,CD9,and CD41 were highly expressed on PRP-exos surface(P<0.001,P=0.025,P=0.004,and P=0.032).The isolated SCs expressed S100β,and PRP-exos could be taken up by SCs.PRP-exos of 40,80,and 160 μg/ml promoted the proliferation of SCs,and that of 40 μg/ml showed the best performance(all P<0.01). Conclusions High concentrations of PRP-exos can be extracted from PRP.PRP-exos can be taken up by SCs and promote the proliferation of SCs cultured in vitro.

The action mechanism of glioblastoma cell-derived exosome: a review / 生物工程学报

Patients with glioblastoma (GBM) generally have a bad prognosis and short overall survival after being treated with surgery, chemotherapy or radiotherapy due to the histological heterogeneity, strong invasive ability and rapid postoperative recurrence of GBM. The components of GBM cell-derived exosome (GBM-exo) can regulate the proliferation and migration of GBM cell via cytokines, miRNAs, DNA molecules and proteins, promote the angiogenesis via angiogenic proteins and non-coding RNAs, mediate tumor immune evasion by targeting immune checkpoints with regulatory factors, proteins and drugs, and reduce drug resistance of GBM cells through non-coding RNAs. GBM-exo is expected to be an important target for the personalized treatment of GBM and a marker for diagnosis and prognosis of this kind of disease. This review summarizes the preparation methods, biological characteristics, functions and molecular mechanisms of GBM-exo on cell proliferation, angiogenesis, immune evasion and drug resistance of GBM to facilitate developing new strategies for the diagnosis and treatment of GBM.

Application of hydrogel-loaded stem cell exosomes in the field of tissue regeneration / 生物工程学报

In recent years, mesenchymal stem cell (MSCs)-derived exosomes have attracted much attention in the field of tissue regeneration. Mesenchymal stem cell-derived exosomes are signaling molecules for communication among cells. They are characterized by natural targeting and low immunogenicity, and are mostly absorbed by cells through the paracrine pathway of mesenchymal stem cells. Moreover, they participate in the regulation and promotion of cell or tissue regeneration. As a scaffold material in regenerative medicine, hydrogel has good biocompatibility and degradability. Combining the two compounds can not only improve the retention time of exosomes at the lesion site, but also improve the dose of exosomes reaching the lesion site by in situ injection, and the therapeutic effect in the lesion area is significant and continuous. This paper summarizes the research results of the interaction of exocrine and hydrogel composite materials to promote tissue repair and regeneration, in order to facilitate research in the field of tissue regeneration in the future.

Effect of circulating exosomes in patients with sepsis on T cell function / 中华危重病急救医学

OBJECTIVE@#To investigate the effect of circulating exosomes (EXO) on T cell function in patients with sepsis.@*METHODS@#Plasma EXO were obtained by ultracentrifugation from 10 patients with sepsis admitted to the emergency intensive care unit of Guangdong Provincial People's Hospital Affiliated to Southern Medical University. Transmission electron microscopy observation, nanoparticle tracking analysis (NTA), and Western blotting were used to detect EXO markers to identify their characteristics. Furthermore, peripheral blood mononuclear cells (PBMC) were isolated from the peripheral blood of 5 healthy volunteers, primary T cells were sorted by magnetic beads and expanded in vitro. After 24 hours of intervention with different doses (0, 1, 2.5, 5, 10 mg/L) of circulating EXO in patients with sepsis, T-cell activity was assessed using a cell counting kit-8 (CCK-8). The expression of T cell activation indicators CD69 and CD25 were observed using flow cytometry. Additional evaluations were performed on immunosuppressive indicators including the expression of programmed cell death 1 (PD-1) in CD4+ T cells and the proportion of regulatory T cell (Treg).@*RESULTS@#The identification results confirmed that the successful isolation of EXO from the plasma of sepsis patients. The expression level of circulating EXO in sepsis patients was higher than that in healthy control group (mg/L: 48.78±5.14 vs. 22.18±2.25, P < 0.01). After 24 hours of intervention with 5 mg/L of plasma EXO from sepsis patients, T cells activity began to show suppression [(85.84±0.56)% vs. (100.00±0.00)%, P < 0.05]. As the dosage increased, after 24 hours of intervention with 10 mg/L of EXO, T cells activity was significantly suppressed [(72.44±2.36)% vs. (100.00±0.00)%, P < 0.01]. Compared with the healthy control group, after T cells intervention with plasma EXO from sepsis patients, the expression of early activation marker CD69 was significantly reduced [(52.87±1.29)% vs. (67.13±3.56)%, P < 0.05]. Meanwhile, there was an upregulation of PD-1 expression in T cells [(57.73±3.06)% vs. (32.07±0.22)%, P < 0.01] and an increase in the proportion of Treg [(54.67±1.19)% vs. (24.60±3.51)%, P < 0.01]. However, the expression of the late activation marker CD25 remained stable [(84.77±3.44)% vs. (85.93±2.32)%, P > 0.05].@*CONCLUSIONS@#Circulating EXO in sepsis patients induce T cell dysfunction, which may be a novel mechanism lead to immunosuppression in sepsis.

Expression and Clinical Significance of Exosome Derived MiR-181b-5p in Children with Acute Lymphoblastic Leukemia / 中国实验血液学杂志

OBJECTIVE@#To explore the expression level of exosome derived miR-181b-5p in different disease stages of children with acute lymphoblastic leukemia and its relationship with clinical characteristics.@*METHODS@#Bone marrow plasma samples of 86 children with ALL were collected. Exosomes were extracted by exosome extraction kit, and RNA in exosomes was extracted by TRIzol method. The levels of miR-181b-5p in the blood plasma exosomes of the patients in the newly diagnosed group, relapse group, remission group and control group were detected by qRT- PCR. The difference of miR-181b-5p expression level in each group was compared and analyzed, and the relationship between miR-181b-5p expression level and clinical characteristics was analyzed.@*RESULTS@#The expression level of exosomal miR-181b-5p in the newly diagnosed group and the relapsed group was significantly lower than that in the remission group and the control group (P< 0.05). The expression level of exosomal miR-181b-5p in T-ALL children was higher than that in B-ALL children (P<0.05). The expression level of plasma exosomal miR-181b-5p in male children was higher than that in female children (P<0.01).@*CONCLUSION@#Exosome derived miR-181b-5p changes dynamically in the course of ALL children, and can be used as a marker miRNA to monitor disease status. Exosomes can transmit information in the tumor microenvironment and serve as a potential carrier for biomolecular targeted therapy.

Testicular exosomes disturb the immunosuppressive phenotype of testicular macrophages mediated by miR-155-5p in uropathogenic Escherichia coli-induced orchitis / 亚洲男科学杂志(英文版)

Male reproductive infections are known to shape the immunological homeostasis of the testes, leading to male infertility. However, the specific pathogenesis of these changes remains poorly understood. Exosomes released in the inflammatory microenvironment are important in communication between the local microenvironment and recipient cells. Here, we aim to identify the immunomodulatory properties of inflammatory testes-derived exosomes (IT-exos) and explore their underlying mechanisms in orchitis. IT-exos were isolated using a uropathogenic Escherichia coli (UPEC)-induced orchitis model and confirmed that IT-exos promoted proinflammatory M1 activation with increasing expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in vitro. We further used small RNA sequencing to identify the differential miRNA profiles in exosomes and primary testicular macrophages (TMs) from normal and UPEC-infected testes, respectively, and identified that miR-155-5p was highly enriched in IT-exos and TMs from inflammatory testes. Further study of bone marrow derived macrophages (BMDMs) transfected with miR-155-5p mimic showed that macrophages polarized to proinflammatory phenotype. In addition, the mice that were administrated IT-exos showed remarkable activation of TM1-like macrophages; however, IT-exos with silencing miR-155-5p showed a decrease in proinflammatory responses. Overall, we demonstrate that miR-155-5p delivered by IT-exos plays an important role in the activation of TM1 in UPEC-induced orchitis. Our study provides a new perspective on the immunological mechanisms underlying inflammation-related male infertility.

Viral myocarditis serum exosome-derived miR-320 promotes the apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway and targeting phosphatidylinositol 3-kinase regulatory subunit 1 (Pik3r1) / 细胞与分子免疫学杂志

Objective To investigate the effect of viral myocarditis serum exosomal miR-320 on apoptosis of cardiomyocytes and its mechanism. Methods The model of viral myocarditis mice was established by intraperitoneal injection of Coxsackie virus B3. Serum exosomes were extracted by serum exosome extraction kit and co-cultured with cardiomyocytes. The uptake of exosomes by cardiomyocytes was detected by laser confocal microscopy. Cardiomyocytes were transfected with miR-320 inhibitor or mimic, and the expression level of miR-320 was detected by real-time quantitative PCR. Flow cytometry was used to detect cardiomyocyte apoptosis rate, and the expression levels of B cell lymphoma 2 (Bcl2) and Bcl2-related X protein (BAX) were tested by Western blot analysis. The prediction of miR-320 target genes and GO and KEGG enrichment analysis were tested by online database. The relationship between miR-320 and its target gene phosphoinositide-3-kinase regulatory subunit 1(Pik3r1) was examined by luciferase reporter gene. The effect of miR-320 on AKT/mTOR pathway protein was detected by Western blot analysis. Results Viral myocarditis serum exosomes promoted cardiomyocyte apoptosis, and increased the level of BAX while the level of Bcl2 was decreased. miR-320 was significantly up-regulated in myocardial tissue of viral myocarditis mice, and both pri-miR-320 and mature of miR-320 were up-regulated greatly in cardiomyocytes. The level of miR-320 in cardiomyocytes treated with viral myocarditis serum exosomes was significantly up-regulated, while transfection of miR-320 inhibitor counteracted miR-320 overexpression and reduced apoptosis rate caused by exosomes. Pik3r1 is the target gene of miR-320, and its overexpression reversed cardiomyocyte apoptosis induced by miR-320 up-regulation. The overexpression of miR-320 inhibited AKT/mTOR pathway activation. Conclusion Viral myocarditis serum exosome-derived miR-320 promotes apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway by targeting Pik3r1.

miR-30e-3p in natural killer cell-derived exosomes inhibits the proliferation and invasion of human esophageal squamous carcinoma cells / 细胞与分子免疫学杂志

Objective To investigate the effects of natural killer (NK)-cell-derived miR-30e-3p-containing exosomes (Exo) on esophageal squamous cell carcinoma (ESCC) cell proliferation, apoptosis and invasion. Methods NK cells were isolated and amplified from the peripheral blood of healthy donors, and NK cell-derived Exo was isolated and identified, which were further co-cultured with NEC cells and were randomly grouped into Exo1 and Exo2 groups. Transmission electron microscopy (TEM) was used to observe the morphology and size of exosomes. Western blot analysis was used to detect the expression levels of exosome markers apoptosis related gene 2- interacting protein X(ALIX), tumor susceptibility gene 101(TSG101), CD81 and calnexin. The NC plasmids, mimics and inhibitors of miR030e-3p were respectively delivered into the NK cells, and the corresponding NK cells-derived Exo were co-cultured with NEC cells, which were divided into NC, Exo, mimic and inhibitor groups. CCK-8 assay was used to evaluate cell proliferation, flow cytometry was conducted to determine cell cycle, annexin V-FITC/PI double staining was employed to detect cell apoptosis, and TranswellTM assay was performed to detect cell invasion abilities. Real-time quantitative PCR was used to detect the expression of miR-23b, miR-422a, miR-133b, miR-124, miR-30e-3p and miR-99a in NCE cells and exosomes. Results The percentages of CD56+CD3+ cells and CD56+CD16+ cells in NK cells were (0.071±0.008)% and (90.6±10.6)%, respectively. Exosome isolated from NK cells ranged from 30 nm to 150 nm, and was positive for ALIX, TSG101 and CD81, while negative for calnexin. NK cell-derived Exos inhibited the proliferation, reduced the proportion of S-phase cells and the number of invaded cells of NEC cells, and promoted the apoptosis and the proportion of G1 phase cells. Overexpression of miR-30E-3p in NK cell-derived exosome inhibited the proliferation and invasion of NEC cells, and blocked cell cycle and promoted apoptosis, while knockdown miR-30e-3p in NK cell-derived exosomes did the opposite. Conclusion miR-30e-3p in NK cell-derived exosomes can inhibit the proliferation and invasion of ESCC cells, block their cell cycle and induce their apoptosis.

Effect of exosomes as drug carriers in chemotherapy of pancreatic cancer / 中南大学学报(医学版)

Pancreatic cancer (PC) is a malignant tumor of the digestive tract with poor patient prognosis. The PC incidence is still increasing with a 5-year survival rate of only 10%. At present, surgical resection is the most effective method to treat PC, however, 80% of the patients missed the best time for surgery after they have been diagnosed as PC. Chemotherapy is one of the main treating methods but PC is insensitive to chemotherapy, prone to drug resistance, and is accompanied by many side effects which are related to a lack of specific target. Exosomes are nanoscale vesicles secreted by almost all cell types and can carry various bioactive substances which mediate cell communication and material transport. They are characterized by a low immunogenicity, low cytotoxicity, high penetration potential and homing capacity, and possess the potential of being used as advanced drug carriers. Therefore, it is a hot research topic to use drug-loaded exosomes for tumor therapy. They may alleviate chemotherapy resistance, reduce side effects, and enhance the curative effect. In recent years, exosome drug carriers have achieved considerable results in PC chemotherapy studies.

Functionalized exosome-loaded ginsenoside Rg1 for the treatment of ischemic stroke / 生物工程学报

The aim of this study was to investigate the therapeutic effects and potential mechanism of c(RGDyK) peptide modified mesenchymal stem cell exosomes loaded with ginsenoside Rg1 (G-Rg1) on ischemic stroke. Thread-tying method was used to establish SD rats transient middle cerebral occlusion model (tMCAO). The model rats were randomly divided into tMCAO group, Exo group, free G-Rg1 group, Exo-Rg1 group and cRGD-Exo-Rg1 group, and sham group was used as control. The infarct volume was measured by 2, 3, 5-triphenyltetrachloride (TTC) staining, the changes of neuron and endothelium were observed by immunofluorescence, and the expression of related proteins was detected by Western blotting. The results showed that cRGD-Exo-Rg1 up-regulated the expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factors (HIF-1α) by activating PI3K/AKT pathway, thus promoting angiogenesis and neurogenesis, effectively reducing the volume of cerebral infarction and improving neural function. In addition, the delivery of cRGD-Exo-Rg1 to ischemic brain tissue up-regulated the expression of occludin and claudin-5, and reduced the injury of blood-brain barrier. Taken together, cRGD-Exo-Rg1 was effective in the treatment of ischemic stroke by promoting angiogenesis and neurogenesis, which provided experimental evidence for the potential clinical benefits of other neuroprotective therapies.

The role of adipose-derived exosomes in the pathological progression of atherosclerosis / 生理学报

Atherosclerosis is a chronic inflammatory disease of vascular walls with a complex etiology. In recent years, the incidence of atherosclerosis continues to increase with obesity and diabetes as major risk factors. As an important metabolic organ in the body, adipose tissue also has a powerful endocrine function. In the case of obesity and diabetes, various cytokines and exosomes derived from adipose tissue mediate organ-organ/cell-cell crosstalk, and are involved in the occurrence and development of various diseases. As an important intercellular communicator, exosomes regulate the pathological process of various cardiovascular diseases and are closely related to atherosclerosis. In this paper, we reviewed the mechanism of adipose-derived exosomes in atherosclerosis with focus on endothelial dysfunction, inflammatory response, lipid metabolism disorder and insulin resistance, hoping to provide reference for the research, diagnosis and treatment of atherosclerosis.

Exosomes derived from Nr-CWS pretreated MSCs facilitate diabetic wound healing by promoting angiogenesis via the circIARS1/miR-4782-5p/VEGFA axis / 中国天然药物

Mesenchymal stem cell (MSC)-derived exosomes (Exos) were reported to a prospective candidate in accelerating diabetic wound healing due to their pro-angiogenic effect. MSCs pretreated with chemistry or biology factors were reported to advance the biological activities of MSC-derived exosomes. Hence, this study was designed to explore whether exosomes derived from human umbilical cord MSCs (hucMSCs) preconditioned with Nocardia rubra cell wall skeleton (Nr-CWS) exhibited superior proangiogenic effect on diabetic wound repair and its underlying molecular mechanisms. The results showed that Nr-CWS-Exos facilitated the proliferation, migration and tube formation of endothelial cells in vitro. In vivo, Nr-CWS-Exos exerted great effect on advancing wound healing by facilitating the angiogenesis of wound tissues compared with Exos. Furthermore, the expression of circIARS1 increased after HUVECs were treated with Nr-CWS-Exos. CircIARS1 promoted the pro-angiogenic effects of Nr-CWS-Exos on endothelial cellsvia the miR-4782-5p/VEGFA axis. Taken together, those data reveal that exosomes derived from Nr-CWS-pretreated MSCs might serve as an underlying strategy for diabetic wound treatment through advancing the biological function of endothelial cells via the circIARS1/miR-4782-5p/VEGFA axis.

NDFIP1 limits cellular TAZ accumulation via exosomal sorting to inhibit NSCLC proliferation

NDFIP1 has been previously reported as a tumor suppressor in multiple solid tumors, but the function of NDFIP1 in NSCLC and the underlying mechanism are still unknown. Besides, the WW domain containing proteins can be recognized by NDFIP1, resulted in the loading of the target proteins into exosomes. However, whether WW domain-containing transcription regulator 1 (WWTR1, also known as TAZ) can be packaged into exosomes by NDFIP1 and if so, whether the release of this oncogenic protein via exosomes has an effect on tumor development has not been investigated to any extent. Here, we first found that NDFIP1 was low expressed in NSCLC samples and cell lines, which is associated with shorter OS. Then, we confirmed the interaction between TAZ and NDFIP1, and the existence of TAZ in exosomes, which requires NDFIP1. Critically, knockout of NDFIP1 led to TAZ accumulation with no change in its mRNA level and degradation rate. And the cellular TAZ level could be altered by exosome secretion. Furthermore, NDFIP1 inhibited proliferation in vitro and in vivo, and silencing TAZ eliminated the increase of proliferation caused by NDFIP1 knockout. Moreover, TAZ was negatively correlated with NDFIP1 in subcutaneous xenograft model and clinical samples, and the serum exosomal TAZ level was lower in NSCLC patients. In summary, our data uncover a new tumor suppressor, NDFIP1 in NSCLC, and a new exosome-related regulatory mechanism of TAZ.

Promising applications of human-derived saliva biomarker testing in clinical diagnostics / 国际口腔科学杂志·英文版

Saliva testing is a vital method for clinical applications, for its noninvasive features, richness in substances, and the huge amount. Due to its direct anatomical connection with oral, digestive, and endocrine systems, clinical usage of saliva testing for these diseases is promising. Furthermore, for other diseases that seeming to have no correlations with saliva, such as neurodegenerative diseases and psychological diseases, researchers also reckon saliva informative. Tremendous papers are being produced in this field. Updated summaries of recent literature give newcomers a shortcut to have a grasp of this topic. Here, we focused on recent research about saliva biomarkers that are derived from humans, not from other organisms. The review mostly addresses the proceedings from 2016 to 2022, to shed light on the promising usage of saliva testing in clinical diagnostics. We recap the recent advances following the category of different types of biomarkers, such as intracellular DNA, RNA, proteins and intercellular exosomes, cell-free DNA, to give a comprehensive impression of saliva biomarker testing.

Research Progress of Exosomes and Their Forensic Significance / 法医学杂志

Exosomes are membranous tiny vesicles secreted by cells, which are widely found in the extracellular matrix and various body fluids and carry a variety of biologically functional molecules such as proteins, lipids, messenger RNA (mRNA) and microRNA (miRNA). Exosomes not only play important biological roles in the field of immunology and oncology, but also have potential application value in the field of forensic medicine. This article reviews the discovery, production and degeneration mechanism, biological functions, isolation and identification methods of exosomes, summarizes the research on exosomes and their significance in the field of forensic science, and discusses their applications in body fluid identification, individual identification, postmortem interval estimation to provide ideas for the application of exosomes in forensic work.

Melanoma stem cells promote metastasis via exosomal miR-1268a inactivation of autophagy

BACKGROUND: Metastatic melanoma has a high mortality rate and poor survival. This is associated with efficient metastatic colonization, but the underlying mechanisms remain elusive. Communication between cancer stem cells (CSCs) and cancer cells plays an important role in metastatic dissemination. Whether cancer stem cells can alter the metastatic properties of non-CSC cells; and whether exosomal crosstalk can mediate such interaction, have not been demonstrated in melanoma prior to this report. RESULTS: The results revealed that exosomes secreted by highly metastatic melanoma CSCs (OL-SCs) promoted the invasiveness of the low metastatic melanoma cells (OL) and accelerated metastatic progression. miR-1268a was up-regulated in cells and exosomes of OL-SCs. Moreover, OL-SCs-derived exosomal miR-1268a, upon taking up by OL cells, promoted the metastatic colonization ability of OL cells in vitro and in vivo. In addition, the pro-metastatic activity of exosomal miR-1268a is achieved through inhibition of autophagy. CONCLUSION: Our study demonstrates that OL cells can acquire the "metastatic ability" from OL-SCs cells. OL-SCs cells achieves this goal by utilizing its exosomes to deliver functional miRNAs, such as miR-1268a, to the targeted OL cells which in turn augments metastatic colonization by inactivating the autophagy pathway in OL cells.

MicroRNAs and exosomes: promising new biomarkers in acute myeloid leukemias?

ABSTRACT Despite advances in understanding of carcinogenesis and of treatment of acute myeloid leukemia, this neoplasm still has a lethality of at least 30%. The search for biomarkers that can predict the response to treatment in the early stages of the disease is still necessary. In recent years, a new form of cellular communication between tumor and non-neoplastic cells has been discovered: the exchange of information through extracellular vesicles. These are small vesicles released by membrane-coated cells that carry proteins, lipids, messenger RNAs, microRNA and DNA, which can be internalized and promote biological changes in target cells. Exosomes are qualified as a type of extracellular vesicle and, in tumors, carry immunoinhibitory signals that promote the escape of immune control. Recent studies have showed their involvement in communication with the cells of the tumor microenvironment and with chemoresistance in several tumors. To date, there is no information about immunoregulatory microRNAs transported by exosomes and their correlation with clinical evolution during chemotherapy for acute myeloid leukemia. Knowledge about immunomodulatory microRNAs obtained by leukemic cells and transported by exosomes can direct us towards the design of new diagnostic and treatment tools in this type of leukemia.

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.

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.

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.