Severe immunosuppression is a hallmark of colorectal cancer(CRC).Myeloid-derived suppressor cells(MDSCs),one of the most abundant components of the tumor stroma,play an important role in the invasion,metastasis,and im...Severe immunosuppression is a hallmark of colorectal cancer(CRC).Myeloid-derived suppressor cells(MDSCs),one of the most abundant components of the tumor stroma,play an important role in the invasion,metastasis,and immune escape of CRC.MDSCs create an immunosuppressive microenvironment by inhibiting the proliferation and activation of immunoreactive cells,including T and natural killer cells,as well as by inducing the proliferation of immunosuppressive cells,such as regulatory T cells and tumor-associated macrophages,which,in turn,promote the growth of cancer cells.Thus,MDSCs are key contributors to the emergence of an immunosup-pressive microenvironment in CRC and play an important role in the breakdown of antitumor immunity.In this narrative review,we explore the mechanisms through which MDSCs contribute to the immunosuppressive microenvironment,the current therapeutic approaches and technologies targeting MDSCs,and the therapeutic potential of modulating MDSCs in CRC treatment.This study provides ideas and methods to enhance survival rates in patients with CRC.展开更多
BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untran...BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untranslated region(UTR)point mutations in ankyrin repeat domain containing 26(ANKRD26).Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1)have been identified as negative regulators of ANKRD26.However,the positive regulators of ANKRD26 are still unknown.AIM To prove the positive regulatory effect of GATA binding protein 2(GATA2)on ANKRD26 transcription.METHODS Human induced pluripotent stem cells derived from bone marrow(hiPSC-BM)INTRODUCTION Ankyrin repeat domain containing protein 26(ANKRD26)acts as a regulator of adipogenesis and is involved in the regulation of feeding behavior[1-3].The ANKRD26 gene is located on chromosome 10 and shares regions of homology with the primate-specific gene family POTE.According to the Human Protein Atlas database,the ANKRD26 protein is localized to the Golgi apparatus and vesicles,and its expression can be detected in nearly all human tissues[4].Moreover,UniProt annotation revealed that ANKRD26 is localized in the centrosome and contains coiled-coil domains formed by spectrin helices and ankyrin repeats[5,6].The most common disease related to ANKRD26 is thrombocytopenia 2(THC2),which is a rare autosomal dominant inherited disease characterized by lifelong mild-to-moderate thrombocytopenia and mild bleeding[7-9].Caused by the variants in the 5’-untranslated region(UTR)of ANKRD26,THC2 is defined by a decrease in the number of platelets in circulating blood and results in increased bleeding and decreased clotting ability[8,10].Due to the point mutations that occur in the 5’-UTR of ANKRD26,its negative transcription factors(TFs),Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1),lose their repression effect[11].The persistent expression of ANKRD26 increases the activity of the mitogen activated protein kinase and extracellular signal regulated kinase 1/2 signaling pathways,which are potentially involved in the regulation of thrombopoietin-dependent signaling and further impair proplatelet formation by megakaryocytes(MKs)[11].However,the positive regulators of ANKRD26,which might be associated with THC2 pathology,are still unknown.展开更多
BACKGROUND： Myeloid-derived suppressor cells （MDSCs） are heterogeneous cell types that suppress T-cell responses in cancer patients and animal models, some MDSC subpopulations are increased in patients with pancrea...BACKGROUND： Myeloid-derived suppressor cells （MDSCs） are heterogeneous cell types that suppress T-cell responses in cancer patients and animal models, some MDSC subpopulations are increased in patients with pancreatic cancer. The present study was to investigate a specific subset of MDSCs in patients with pancreatic cancer and the mechanism of MDSCs increase in these patients. METHODS： Myeloid cells from whole blood were collected from 37 patients with pancreatic cancer, 17 with cholangiocarcinoma, and 47 healthy controls. Four pancreatic cancer cell lines were co- cultured with normal peripheral blood mononudear cells （PBMCs） to test the effect of tumor cells on the conversion of PBMCs to MDSCs. Levels of granulocyte-macrophage colony-stimulating factor （GM-CSF） and arginase activity in the plasma of cancer patients were analyzed by enzyme-linked immunosorbent assay. RESULTS： CD14＋/CD11b＋/HLA-DR MDSCs were increased in patients with pancreatic or bile duct cancer compared with those in healthy controls, and this increase was correlated with clinical cancer stage. Pancreatic cancer cell lines induced PBMCs to MDSCs in a dose-dependent manner. GM-CSF and arginase activity levels were significantly increased in the se rum of patients with pancreatic cancer. CONCLUSIONS： MDSCs were tumor related： tumor cells induced PBMCs to MDSCs in a dose-dependent manner and circulating CD14＋/CD11b＋/HLA-DR- MDSCs in pancreatic cancer patients were positively correlated with tumor burden. MDSCs might be useful markers for pancreatic cancer detection and progression.展开更多
Myeloid-derived suppressor cells(MDSCs) represent an important class of immunoregulatory cells that can be activated to suppress T cell functions. These MDSCs can inhibit T cell functions through cell surface interact...Myeloid-derived suppressor cells(MDSCs) represent an important class of immunoregulatory cells that can be activated to suppress T cell functions. These MDSCs can inhibit T cell functions through cell surface interactions and the release of soluble mediators. MDSCs accumulate in the inflamed tissues and lymphoid organs of patients with autoimmune diseases. Much of our knowledge of MDSC function has come from studies involving cancer models, however many recent studies have helped to characterize MDSC involvement in autoimmune diseases. MDSCs are a heterogeneous group of immature myeloid cells with a number of different functions for the suppression of T cell responses. However, we have yet to fully understand their contributions to the development and regulation of autoimmune diseases. A number of studies have described beneficial functions of MDSCs during autoimmune diseases, and thus there appears to be a potential role for MDSCs in the treatment of these diseases. Nevertheless, many questions remain as to the activation, differentiation, and inhibitory functions of MDSCs. This review aims to summarize our current knowledge of MDSC subsets and suppressive functions in tissue-specific autoimmune disorders. We also describe the potential of MDSC-basedcell therapy for the treatment of autoimmune diseases and note some of hurdles facing the implementation of this therapy.展开更多
Myeloid-derived suppressor cells （MDSCs） play a crucial role in T cell dysfunction, which is related to poor outcome in patients with severe trauma. Cyclooxygenase-2 （Cox-2） contributes to immune disorder in traum...Myeloid-derived suppressor cells （MDSCs） play a crucial role in T cell dysfunction, which is related to poor outcome in patients with severe trauma. Cyclooxygenase-2 （Cox-2） contributes to immune disorder in trauma and infection via production of prostaglandin E2. However, the role of Cox-2 in the accumulation and function of MDSCs after traumatic stress has not been fully elucidated. In the present study, we treated murine trauma model with NS398, a selective Cox-2 inhibitor. Then the percentages of CD1 lb＋/Gr-l＋ cells, proliferation and apoptosis of CD4＋ T cells were determined. Ar- ginase activity and arginase-1 （Arg-1） protein expression of splenic CDllb＋/Gr-I＋ cells, and de- layed-type hypersensitivity （DTH） response were analyzed. The results showed that Cox-2 blockade significantly decreased the percentages of CD1 lb＋/Gr-l＋ cells in the spleen and bone marrow 48 and 72 h after traumatic stress. NS398 inhibited arginase activity and down-regulated the Arg-1 expression of splenic CD1 lb＋/Gr-l＋ ceils. Moreover, NS398 could promote proliferation and inhibit apoptosis of CD4＋ T cells. It also restored DTH response of traumatic mice. Taken together, our data revealed that Cox-2 might play a pivotal role in the accumulation and function of MDSC after traumatic stress.展开更多
AIM: To perform a comprehensive investigation into the potential correlation between circulating myeloidderived suppressor cells (MDSCs) and Th17 cells in esophageal cancer (ECA). METHODS: A total of 31 patients newly...AIM: To perform a comprehensive investigation into the potential correlation between circulating myeloidderived suppressor cells (MDSCs) and Th17 cells in esophageal cancer (ECA). METHODS: A total of 31 patients newly diagnosed with ECA and 26 healthy subjects were included in the current study. The frequencies of MDSCs and Th17 cells in peripheral blood were determined by flow cytometry. The mRNA expression of cytokines, arginase 1 (Arg1) and inducible NO synthase (iNOS) in peripheral blood mononuclear cells (PBMCs) and plasma Arg1 were assessed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: There was an increased prevalence of MDSCs in the peripheral blood from ECA patients (15.21% ± 2.25%) when compared with healthy control (HC) (1.10% ± 0.12%, P < 0.0001). The plasma levels of Arg1 in ECA patients were significantly higher than those in HC (28.28 ± 4.10 ng/mL vs 9.57 ± 1.51 ng/ mL, P=0.0003). iNOS mRNA levels in the peripheral blood of ECA patients also showed a threefold increase compared with HC (P=0.0162). The frequencies of Th17 cells (CD4 + IL-17A + ) were significantly elevated in ECA patients versus HC (3.50% ± 0.33% vs 1.82% ± 0.19%, P=0.0001). Increased mRNA expression of IL-17 and ROR-γt was also observed in ECA patients compared with HC (P=0.0041 and P=0.0004, respectively), while the mRNA expression of IL-6 and tumor necrosis factor-α (TNF-α) showed significant decreases (P=0.0049 and P < 0.0001, respectively). No obvious correlations were found between the frequencies of MDSCs and Th17 cells in the peripheral blood from ECA patients(r=-0.1725, P=0.3534). Arg1 mRNA levels were positively correlated with levels of IL-6 (r=0.6404, P=0.0031) and TNF-α (r=0.7646, P=0.0001). Similarly, iNOS mRNA levels were also positively correlated with levels of IL-6 (r=0.6782, P=0.0007) and TNF-α (r=0.7633, P < 0.0001). CONCLUSION: This study reveals the relationship between circulating MDSCs and Th17 cells, which may lead to new immunotherapy approaches for ECA based on the associated metabolites and cytokines.展开更多
Purpose: A series of clinical studies have established the safety and efficacy of transcatheter arterial chemoembolization(TACE) with gelatin sponge microparticles(GSMs) in treating hepatocellular carcinoma(HCC). HCC ...Purpose: A series of clinical studies have established the safety and efficacy of transcatheter arterial chemoembolization(TACE) with gelatin sponge microparticles(GSMs) in treating hepatocellular carcinoma(HCC). HCC can lead to obvious necrosis inside tumors, especially larger ones, although it is unclear whether such necrotic tumor tissue can induce favorable immune reactions against the tumor. Myeloid-derived suppressor cells(MDSCs)have immunosuppressive functions and are currently considered a very important cell type affecting tumor immunity. This study observed changes in MDSC frequency in peripheral blood before and after GSM–TACE to evaluate the effect on the immune function of HCC patients.Methods: Eight patients diagnosed with HCC underwent GSM–TACE treatment in the Hepatobiliary Interventional Department of Beijing Tsinghua Chang Gung Hospital, Beijing, China;we followed up with the patients over a period of 30 days post-surgery. We used flow cytometry(FCM) to quantify the frequency of MDSCs in peripheral blood before TACE, 10 days after surgery and 30 days after surgery.Results: MDSC frequency after GSM–TACE had a significant downward trend. Pre-TACE, it was 30.73% ? 11.93%,decreasing to 18.60% ? 11.37% at 10 days after operation. This decrease was not statistically significant(P > 0.05). MDSC frequency was even lower 30 days after TACE(7.63% ? 7.32%) than at 10 days after TACE(P < 0.05), and there was a significant difference compared with pre-TACE(P < 0.001). We evaluated tumor response at 30 days after GSM–TACE according to the Modified Response Evaluation Criteria in Solid Tumors(mRECIST), and all eight patients showed partial response(PR).Conclusion: Our results confirmed that GSM–TACE was beneficial for improving anti-tumor immunity in the treatment of HCC.展开更多
The effects of granulocyte colony-stimulation-factor （G-CSF） on stem cell mobilization and its impact on the amplification of myeloid-derived suppressor cells （MDSCs） of donor mice were ex- amined. A mouse model o...The effects of granulocyte colony-stimulation-factor （G-CSF） on stem cell mobilization and its impact on the amplification of myeloid-derived suppressor cells （MDSCs） of donor mice were ex- amined. A mouse model of stem cell mobilization was established by consecutive subcutaneous injec- tion of 100 μg/kg G-CSF for 5 days. The blood from the donor mice was routinely examined during mobilization. Stem cells and MDSCs were analyzed by flow cytometry. The immunosuppressive mole- cules derived from MDSCs in serum and spleen, including hydrogen dioxide （H202） and nitric oxide （NO）, and the activity of nitric oxide synthase （NOS） were determined during the mobilization. Apop- tosis of T lymphocytes was assessed by using Annexin-V/PI. During stem cell mobilization, the number of lymphocytes and white blood cells in the peripheral blood was increased, and peaked on the 4th day. The number of stem cells in G-CSF-treated mice was significantly greater than that in controls （P〈0.01）. The expansions of MSDCs were also observed after G-CSF mobilization, with a more notable rate of growth in the peripheral blood than in the spleen. The activity of NOS and the production of NO were increased in the donor mice, and the serum H202 levels were approximately 4-fold greater than the con- trois. Consequently, apoptosis of T lymphocytes was increased and showed a positive correlation with the elevated percentage of MDSCs. It was concluded that G-CSF could provide sufficient peripheral blood stem cells for transplantation. Exogenous administration of G-CSF caused the accumulation of MDSCs in the peripheral blood and the spleen, which could lead to apoptosis ofT lymphocytes and may offer a new strategy for the prevention and treatment of graft versus host disease.展开更多
Objective Elevated myeloid-derived suppressor cells(MDSCs)in many malignancies are associated with the increased risk for metastases and poor prognosis.Therefore,a mouse model of intraocular melanoma was established t...Objective Elevated myeloid-derived suppressor cells(MDSCs)in many malignancies are associated with the increased risk for metastases and poor prognosis.Therefore,a mouse model of intraocular melanoma was established to explore how MDSCs influence liver metastases.Methods In this study,murine B16LS melanoma cells were transplanted into the posterior compartment(PC)of the eye of C57BL/6 mice.Leucocytes from the liver of naive mice and mice bearing melanoma liver metastasis were isolated using isotonic Percoll centrifugation,examined by flow cytometry for their expression of Gr1,CD11b,F4/80,RAE-1,and Mult-1,and further isolated for MDSCs and natural killer(NK)cells.The effects of MDSCs on NK cells were tested by coculturing and assessing the ability of NK cells to produce interferon-gamma(IFN-γ)by ELISA and NK cell cytotoxicity by 3H-thymidine incorporation assay.The impact of IFN-γon liver metastases was examined via selectively depleting IFN-γin vivo.Results The results showed that mice with liver metastases had increased levels of CD11b+Gr1+F4/80+as well as CD11b+Gr1+F4/80−MDSCs.MDSCs significantly enhanced the generation of IFN-γtogether with the cytotoxicity of the NK cells.Furthermore,these effects were cell-cell contact-dependent.Although IFN-γwas not of a toxic nature to the melanoma cells,it profoundly inhibited B16LS cell proliferation.Depleting IFN-γin vivo led to increased liver metastases.Conclusion All these findings first revealed that MDSCs accumulated in liver metastasis of intraocular melanoma could activate the NK cells to produce an effective anti-tumor immune response.Thus,the MDSCs’performance in different tumor models would need more investigation to boost current immunotherapy modalities.展开更多
Gastrointestinal(GI)cancers are one of the most common malignancies worldwide,with high rates of morbidity and mortality.Myeloid-derived suppressor cells(MDSCs)are major components of the tumor microenvironment(TME).M...Gastrointestinal(GI)cancers are one of the most common malignancies worldwide,with high rates of morbidity and mortality.Myeloid-derived suppressor cells(MDSCs)are major components of the tumor microenvironment(TME).MDSCs facilitate the transformation of premalignant cells and play roles in tumor growth and metastasis.Moreover,in patients with GI malignancies,MDSCs can lead to the suppression of T cells and natural killer cells.Accordingly,a better understanding of the role and mechanism of action of MDSCs in the TME will aid in the development of novel immune-targeted therapies.展开更多
Lysosomal acid lipase （LAL） cleaves cholesteryl esters （CE） and triglycerides （TG） to generate cholesterol and free fatty acid in lysosomes of cells. The down-stream metabolic products of fatty acids are ligands...Lysosomal acid lipase （LAL） cleaves cholesteryl esters （CE） and triglycerides （TG） to generate cholesterol and free fatty acid in lysosomes of cells. The down-stream metabolic products of fatty acids are ligands for activation of peroxisome proliferator-activated re-ceptor gamma （PPARγ）. Accumulation of CEs and TGs is resulted from lack of functional LAL in lysosomes of cells, especially in myeloid cells. One characteristic phenotype in LAL knock-out （ lal-/- ） mice is systemic elevation of myeloid-derived suppressive cells （MDSCs）. MDSCs infltrate into multiple distal organs, alter T cell development, and suppress T cell proliferation and lym-phokine production in lal-/- mice, which lead to severe pathogeneses in multiple organs. The gene transcrip-tional profle analysis in MDSCs from the bone marrow has identified multiple defects responsible for MDSCs malformation and malfunction in lal-/- mice, including G protein signaling, cell cycles, glycolysis metabolism, mitochondrial bioenergetics, mTOR pathway etc. In a sep-arate gene transcriptional profle analysis in the lung of lal-/- mice, matrix metalloproteinase 12 （MMP12） and apoptosis inhibitor 6 （Api6） are highly overexpressed due to lack of ligand synthesis for PPARγ. PPARγ nega-tively regulates MMP12 and Api6. Blocking the PPAR signaling by overexpression of a dominant negative PPARγ （dnPPARγ） form, or overexpressing MMP12 or Api6 in myeloid or lung epithelial cells in inducible transgenic mouse models results in elevated MDSCs and infammation-induced tumorigenesis. These stud-ies demonstrate that LAL and its downstream effectors are critical for MDSCs development, differentiation and malfunction.展开更多
Cancer vaccines to date have not broadly achieved a significant impact on the overall survival of patients. The negative effect on the immune system of the tu-mor itself and conventional anti-tumor treatments such as ...Cancer vaccines to date have not broadly achieved a significant impact on the overall survival of patients. The negative effect on the immune system of the tu-mor itself and conventional anti-tumor treatments such as chemotherapy is, undoubtedly, a key reason for these disappointing results. Myeloid-derived suppres-sor cells （MDSCs） are considered a central node of the immunosuppressive network associated with tumors. These cells inhibit the effector function of natural killer and CD8＋ T cells, expand regulatory T cells and can differentiate into tumor-associated macrophages within the tumor microenvironment. Thus, overcoming the suppressive effects of MDSCs is likely to be criti-cal for cancer immunotherapy to generate effective anti-tumor immune responses. However, the capacity of cancer vaccines and particularly their adjuvants to overcome this inhibitory population has not been well characterized. Very small size proteoliposomes （VSSP） is a nanoparticulated adjuvant specifcally designed to be formulated with vaccines used in the treatment of immunocompromised patients. This adjuvant contains immunostimulatory bacterial signals together with GM3 ganglioside. VSSP promotes dendritic cell maturation, antigen cross-presentation to CD8＋ T cells, Th1 polar-ization, and enhances CD8＋ T cell response in tumor-free mice. Currently, four cancer vaccines using VSSP as the adjuvant are in Phase？Ⅰ？and Ⅱ clinical trials. In this review, we summarize our work characterizing the unique ability of VSSP to stimulate antigen-specifc CD8＋ T cell responses in two immunocompromised sce-narios; in tumor-bearing mice and during chemother-apy-induced leukopenia. Particular emphasis has been placed on the interaction of these nanoparticles with MDSCs, as well as comparison with other cancer vac-cine adjuvants currently in preclinical or clinical studies.展开更多
Glioblastoma(GBM)is a highly aggressive and lethal brain tumor with an immunosuppressive tumor microenvironment(TME).In this environment,myeloid cells,such as myeloid-derived suppressor cells(MDSCs),play a pivotal rol...Glioblastoma(GBM)is a highly aggressive and lethal brain tumor with an immunosuppressive tumor microenvironment(TME).In this environment,myeloid cells,such as myeloid-derived suppressor cells(MDSCs),play a pivotal role in suppressing antitumor immunity.Lipometabolism is closely related to the function of myeloid cells.Here,our study reports that acetyl-CoA acetyltransferase 1(ACAT1),the key enzyme of fatty acid oxidation(FAO)and ketogenesis,is significantly downregulated in the MDSCs infiltrated in GBM patients.To investigate the effects of ACAT1 on myeloid cells,we generated mice with myeloid-specific(LyzM-cre)depletion of ACAT1.The results show that these mice exhibited a remarkable accumulation of MDSCs and increased tumor progression both ectopically and orthotopically.The mechanism behind this effect is elevated secretion of C-X-C motif ligand 1(CXCLI)of macrophages(Mo).Overall,our findings demonstrate that ACAT1 could serve as a promising drug target for GBM by regulating the function of MDSCs in the TME.展开更多
Growing evidence suggests that myeloid-derived suppressor cells （MDSCs）,which have been named ＂immature myeloid cells＂ or ＂myeloid suppressor cells＂ （MSCs）,play a critical role during the progression of cancer...Growing evidence suggests that myeloid-derived suppressor cells （MDSCs）,which have been named ＂immature myeloid cells＂ or ＂myeloid suppressor cells＂ （MSCs）,play a critical role during the progression of cancer in tumor-bearing mice and cancer patients.As their name implies,these cells are derived from bone marrow and have a tremendous potential to suppress immune responses.Recent studies indicated that these cells also have a crucial role in tumor progression.MDSCs can directly incorporate into tumor endothelium.They secret many pro-angiogenic factors as well.In addition,they play an essential role in cancer invasion and metastasis through inducing the production of matrix metalloproteinases （MMPs）,chemoattractants and creating a pre-metastatic environment.Increasing evidence supports the idea that cancer stem cells （CSCs） are responsible for tumorigenesis,resistance to therapies,invasion and metastasis.Here,we hypothesize that CSCs may ＂hijack＂ MDSCs for use as alternative niche cells,leading to the maintenance of stemness and enhanced chemo-and radio-therapy resistance.The countermeasure that directly targets to MDSCs may be useful for against angiogenesis and preventing cancer from invasion and metastasis.Therefore,the study of MDSCs is important to understand tumor progression and to enhance the therapeutic efficacy against cancer.展开更多
Background Hemorrhagic shock is usually associated with complicated immune and inflammatory responses, which are sometimes crucial for the prognosis. As regulators of the immune and inflammatory system; proliferation,...Background Hemorrhagic shock is usually associated with complicated immune and inflammatory responses, which are sometimes crucial for the prognosis. As regulators of the immune and inflammatory system; proliferation, migration, distribution and activation of myeloid-derived suppressor cells （MDSCs） are intimately linked to the inflammation cascade. Methods In a model of severe hemorrhagic shock, thirty-five rats were randomly divided into control, sham, normal saline resuscitation （NS）, hypertonic saline resuscitation （HTS）, and hydroxyethyl starch resuscitation （HES）, with seven in each group. MDSCs were analyzed by flow cytometric staining of CD11b/c＊Gra~ in peripheral blood mononuclear cells （PBMC）, spleen cell suspensions, and bone marrow nucleated cells （BMNC）. Simultaneously, the expressions of arginase-1 （ARG-1） and inducible nitric oxide synthase （iNOS） mRNA in MDSCs were evaluated by quantitative reverse transcription-polymerase chain reaction （qRT-PCR）. Results In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the MDSCs in the PBMC of NS, HTS and HES groups markedly increased, and MDSCs in BMNC of these groups decreased accordingly, significantly different to the control group. In hemorrhagic shock rats infused with HTS at the early resuscitation stage, MDSCs in PBMC increased about 2 and 4 folds, and MDSCs in BMNC decreased about 1.3 and 1.6 folds, as compared to the sham group respectively, with statistically significant difference. Furthermore, compared to the NS and HES groups, the MDSCs in PBMC of HTS group increased 1.6 and 1.8 folds with statistically significant differences; the MDSCs decrease in BMNC was not significant. However, there was no statistically significant difference in MDSCs of spleen among the five groups. In addition, compared to the control, sham, NS and HES groups, the ARG-1 and iNOS mRNA of MDSCs in PBMC, spleen and BMNC in the HTS group had the highest level of expression, but no statistically significant differences were noted. Conclusions In this model of rat with severe and controlled hemorrhagic shock, small volume resuscitation with HTS contributes to dramatically early migration and redistribution of MDSCs from bone marrow to peripheral circulation, compared to resuscitation with NS or HES.展开更多
Objective： To observe the intervention effect of Shugan Jianpi Formula （疏肝健脾方,SGJPF） on a breast cancer mouse model with depression and investigate the underlying mechanism of SGJPF in preventing the developme...Objective： To observe the intervention effect of Shugan Jianpi Formula （疏肝健脾方,SGJPF） on a breast cancer mouse model with depression and investigate the underlying mechanism of SGJPF in preventing the development of breast cancer. Metkods： The breast cancer model was induced by inoculation of breast cancer cells, the depression model was induced by chronic stress stimuli, and the depression cancer model was established by combining the two factors. The mice were divided into 7 groups： normal control, depression model, tumor model, depression tumor model, SGJPF, chemotherapy, and SGJPF＋chemotherapy groups. The last 3 groups were depression breast cancer mice and treated respectively with SGJPF, chemotherapy drug gemcitabine （GEM）, and SGJPF alongside GEM. The condition of the mice was evaluated by the expression of 5-hydroxytryptamine in hippocampus after the sucrose water test and open field test, weight change, and survival time. Tumor growth was monitored with in vivo imaging. Flow cytometry was used to analyze the level of myeloid-derived suppression cell （MDSC） in the mouse spleen, T cell subsets, and the early apoptosis of CD8~ T cells, Results： The SGJPF＋GEM group had the highest inhibition rate and the longest survival time （P〈0.01）. The MDSC level and the apoptosis rate of CD8＊ T cells was the highest in the SGJPF＋GEM group （P〈0.05）. Conclusions： Depressive disorders and tumor growth could suppress the immune function of mice to different degrees, and the microenvironment in late 4T1 inflammatory breast cancer may play an important role in the pathological process. SGJYF could regulate the immune microenvironment by reducing CD8＊ T lymphocyte apoptosis and tumor cell activity, increasing immune surveillance capability, and inhibiting MDSC proliferation, thus prolonging the survival time of tumor-bearing mice.展开更多
In recent years,studying the role of myeloid-derived suppressor cells(MDSCs)in many pathological inflammatory conditions has become a very active research area.Although the role of MDSCs in cancer is relatively well e...In recent years,studying the role of myeloid-derived suppressor cells(MDSCs)in many pathological inflammatory conditions has become a very active research area.Although the role of MDSCs in cancer is relatively well established,their role in non-cancerous pathological conditions remains in its infancy resulting in much confusion.Our objectives in this review are to address some recent advances in MDSC research in order to minimize such confusion and to provide an insight into their function in the context of other diseases.The following topics will be specifically focused upon:(1)definition and characterization of MDSCs;(2)whether all MDSC populations consist of immature cells;(3)technical issues in MDSC isolation,estimation and characterization;(4)the origin of MDSCs and their anatomical distribution in health and disease;(5)mediators of MDSC expansion and accumulation;(6)factors that determine the expansion of one MDSC population over the other;(7)the Yin and Yang roles of MDSCs.Moreover,the functions of MDSCs will be addressed throughout the text.展开更多
Myeloid-derived suppressor cells(MDSCs)are a heterogeneous population of immature cells and natural inhibitors of adaptive immunity.Intracellular metabolic changes in MDSCs exert a direct immunological influence on th...Myeloid-derived suppressor cells(MDSCs)are a heterogeneous population of immature cells and natural inhibitors of adaptive immunity.Intracellular metabolic changes in MDSCs exert a direct immunological influence on their suppressive activity.Our previous study demonstrated that high-dose dexamethasone(HD-DXM)corrected the functional impairment of MDSCs in immune thrombocytopenia(ITP);however,the MDSC population was not restored in nonresponders,and the mechanism remained unclear.In this study,altered mitochondrial physiology and reduced mitochondrial gene transcription were detected in MDSCs from HD-DXM nonresponders,accompanied by decreased levels of carnitine palmitoyltransferase-1(CPT-1),a rate-limiting enzyme in fatty acid oxidation(FAO).Blockade of FAO with a CPT-1 inhibitor abolished the immunosuppressive function of MDSCs in HD-DXM responders.We also report that MDSCs from ITP patients had lower expression of the glucocorticoid receptor(GR),which can translocate into mitochondria to regulate the transcription of mitochondrial DNA(mtDNA)as well as the level of oxidative phosphorylation.It was confirmed that the expression of CPT-1 and mtDNA-encoded genes was downregulated in GR-siRNA-treated murine MDSCs.Finally,by establishing murine models of active and passive ITP via adoptive transfer of DXM-modulated MDSCs,we confirmed that GR-silenced MDSCs failed to alleviate thrombocytopenia in mice with ITP.In conclusion,our study indicated that impaired aerobic metabolism in MDSCs participates in the pathogenesis of glucocorticoid resistance in ITP and that intact control of MDSC metabolism by GR contributes to the homeostatic regulation of immunosuppressive cell function.展开更多
Myelodysplastic syndrome （MDS） is a group of clonal .hematopoietic stem cell disorders, characterizedby varying degrees ot peripheral cytopema caused by ineffective dysplasia of the myeloid lineages. MDS also has a ...Myelodysplastic syndrome （MDS） is a group of clonal .hematopoietic stem cell disorders, characterizedby varying degrees ot peripheral cytopema caused by ineffective dysplasia of the myeloid lineages. MDS also has a high risk of progression to acute myeloid leukemia. But the role of immune abnormalities in the pathogenesis of MDS is still not clear. Myeloid-derived suppressor cells （MDSCs） constitute a heterogeneous population of immature cells derived from the bone marrow. In the recent years, MDSCs were reported to play an important role in suppressing lymphocytes in tumor-bearing animal models and cancer patients. This could be one of the mechanisms on tumor immune evasion, which aggravates the development and growth of tumors. In a mice model, MDSCs are characterized by co- expression of GR1 and CDllb. In humans, the phenotype of MDSCs was accepted as Lin- HLA-DR- CD33＋.l In the present study, we investigated the level of circulating MDSCs （Lin- HLA-DR- CD33＋） in patients with MDS and evaluated the association between MDSCs and malignancy in MDS. METHODS Patients Thirty-five patients with MDS （24 men and 11 women, median age 59 years （age range 21-83）, including refractory anemia （n=3）; refractory anemia with ringed sideroblasts （n=3）; refractory cytopenia with multilineage dysplasia （n=9）; refractory anemia with excess blast-I （n=4）; refractory anemia with excess blast-II （n=16））, and without other systemic diseases, were enrolled in the present study. All the patients underwent diagnosis in the Department of Hematology, General Hospital of Tianjin Medical University from March 2011 to April 2012, according to the diagnostic criteria of MDS proposed between 2007 and 2008. After treatment for three months, 14 MDS patients were investigated again for their MDSCs changes. Twenty normal healthy individuals were selected as controls （9 men and 11 women, median age 34 years （age range 26-82））. The study was approved by the Ethics Committee of Tianjin Medical University. Informed written consent was obtained from all the patients and normalindividuals in accordance with the Declaration of Helsinki Flow cytometric analysis Peripheral blood samples were collected in EDTA- anticoagulant tubes from the patients and normal individuals. The number of circulating MDSCs was measured by using flow cytometry （FCM） assay. The markers used in the assay were anti-CD33-APC, anti-LIN- FITC （CD3, CD14, CD16, CD19, CD20, CD56） and anti- HLA-DR-PE antibodies （BD Biosciences, USA）. The number of stem cells from the bone marrow, which was collected in heparin-anticoagulant tubes, was measured by FCM using anti-CD34-PerCP antibodies （BD Biosciences）. Data acquisition and analysis were carried out by using FACS-Calibur flow cytometer （BD Biosciences）, with the Cell Quest software （Becton Dickinson, version 3.1）.展开更多
Immunomodulatory signaling imposes tight regulations on metabolic programs within immune cells and consequentially determines immune response outcomes.Although the glucocorticoid receptor(GR)has been recently implicat...Immunomodulatory signaling imposes tight regulations on metabolic programs within immune cells and consequentially determines immune response outcomes.Although the glucocorticoid receptor(GR)has been recently implicated in regulating the function of myeloid-derived suppressor cells(MDSCs),whether the dysregulation of GR in MDSCs is involved in immune-mediated hepatic diseases and how GR regulates the function of MDSCs in such a context remains unknown.Here,we revealed the dysregulation of GR expression in MDSCs during innate immunological hepatic injury(IMH)and found that GR regulates the function of MDSCs through modulating HIF1α-dependent glycolysis.Pharmacological modulation of GR by its agonist(dexamethasone,Dex)protects IMH mice against inflammatory injury.Mechanistically,GR signaling suppresses HIF1αand HIF1α-dependent glycolysis in MDSCs and thus promotes the immune suppressive activity of MDSCs.Our studies reveal a role of GR-HIF1αin regulating the metabolism and function of MDSCs and further implicate MDSC GR signaling as a potential therapeutic target in hepatic diseases that are driven by innate immune cell-mediated systemic inflammation.展开更多
基金Supported by National Natural Science Foundation of China,No.82320108022,No.82322076 and No.82104466.
文摘Severe immunosuppression is a hallmark of colorectal cancer(CRC).Myeloid-derived suppressor cells(MDSCs),one of the most abundant components of the tumor stroma,play an important role in the invasion,metastasis,and immune escape of CRC.MDSCs create an immunosuppressive microenvironment by inhibiting the proliferation and activation of immunoreactive cells,including T and natural killer cells,as well as by inducing the proliferation of immunosuppressive cells,such as regulatory T cells and tumor-associated macrophages,which,in turn,promote the growth of cancer cells.Thus,MDSCs are key contributors to the emergence of an immunosup-pressive microenvironment in CRC and play an important role in the breakdown of antitumor immunity.In this narrative review,we explore the mechanisms through which MDSCs contribute to the immunosuppressive microenvironment,the current therapeutic approaches and technologies targeting MDSCs,and the therapeutic potential of modulating MDSCs in CRC treatment.This study provides ideas and methods to enhance survival rates in patients with CRC.
基金Supported by General Program of National Natural Science Foundation of China,No.81770197Scientific and Technological Research Major Program of Chongqing Municipal Education Commission,No.KJZD-M202312802+1 种基金Chongqing Natural Science Foundation of China,No.CSTB2022NSCQ-MSX0190,No.CSTB2022NSCQ-MSX0176,and No.cstc2020jcyj-msxmX0051Xinqiao Young Postdoc Talent Incubation Program,No.2022YQB098.
文摘BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untranslated region(UTR)point mutations in ankyrin repeat domain containing 26(ANKRD26).Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1)have been identified as negative regulators of ANKRD26.However,the positive regulators of ANKRD26 are still unknown.AIM To prove the positive regulatory effect of GATA binding protein 2(GATA2)on ANKRD26 transcription.METHODS Human induced pluripotent stem cells derived from bone marrow(hiPSC-BM)INTRODUCTION Ankyrin repeat domain containing protein 26(ANKRD26)acts as a regulator of adipogenesis and is involved in the regulation of feeding behavior[1-3].The ANKRD26 gene is located on chromosome 10 and shares regions of homology with the primate-specific gene family POTE.According to the Human Protein Atlas database,the ANKRD26 protein is localized to the Golgi apparatus and vesicles,and its expression can be detected in nearly all human tissues[4].Moreover,UniProt annotation revealed that ANKRD26 is localized in the centrosome and contains coiled-coil domains formed by spectrin helices and ankyrin repeats[5,6].The most common disease related to ANKRD26 is thrombocytopenia 2(THC2),which is a rare autosomal dominant inherited disease characterized by lifelong mild-to-moderate thrombocytopenia and mild bleeding[7-9].Caused by the variants in the 5’-untranslated region(UTR)of ANKRD26,THC2 is defined by a decrease in the number of platelets in circulating blood and results in increased bleeding and decreased clotting ability[8,10].Due to the point mutations that occur in the 5’-UTR of ANKRD26,its negative transcription factors(TFs),Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1),lose their repression effect[11].The persistent expression of ANKRD26 increases the activity of the mitogen activated protein kinase and extracellular signal regulated kinase 1/2 signaling pathways,which are potentially involved in the regulation of thrombopoietin-dependent signaling and further impair proplatelet formation by megakaryocytes(MKs)[11].However,the positive regulators of ANKRD26,which might be associated with THC2 pathology,are still unknown.
基金supported by grants from the National Natural Science Foundation of China(81071775,81272659,81101621,81160311,81172064,81001068,81272425 and 81101870)National“Eleventh Five-Year”Scientific and Technological Support Projects(2006BAI02A13-402)+1 种基金Key Projects of Science Foundation of Hubei Province(2011CDA030)Research Fund of Young Scholars for the Doctoral Program of Higher Education of China(20110142120014)
文摘BACKGROUND： Myeloid-derived suppressor cells （MDSCs） are heterogeneous cell types that suppress T-cell responses in cancer patients and animal models, some MDSC subpopulations are increased in patients with pancreatic cancer. The present study was to investigate a specific subset of MDSCs in patients with pancreatic cancer and the mechanism of MDSCs increase in these patients. METHODS： Myeloid cells from whole blood were collected from 37 patients with pancreatic cancer, 17 with cholangiocarcinoma, and 47 healthy controls. Four pancreatic cancer cell lines were co- cultured with normal peripheral blood mononudear cells （PBMCs） to test the effect of tumor cells on the conversion of PBMCs to MDSCs. Levels of granulocyte-macrophage colony-stimulating factor （GM-CSF） and arginase activity in the plasma of cancer patients were analyzed by enzyme-linked immunosorbent assay. RESULTS： CD14＋/CD11b＋/HLA-DR MDSCs were increased in patients with pancreatic or bile duct cancer compared with those in healthy controls, and this increase was correlated with clinical cancer stage. Pancreatic cancer cell lines induced PBMCs to MDSCs in a dose-dependent manner. GM-CSF and arginase activity levels were significantly increased in the se rum of patients with pancreatic cancer. CONCLUSIONS： MDSCs were tumor related： tumor cells induced PBMCs to MDSCs in a dose-dependent manner and circulating CD14＋/CD11b＋/HLA-DR- MDSCs in pancreatic cancer patients were positively correlated with tumor burden. MDSCs might be useful markers for pancreatic cancer detection and progression.
文摘Myeloid-derived suppressor cells(MDSCs) represent an important class of immunoregulatory cells that can be activated to suppress T cell functions. These MDSCs can inhibit T cell functions through cell surface interactions and the release of soluble mediators. MDSCs accumulate in the inflamed tissues and lymphoid organs of patients with autoimmune diseases. Much of our knowledge of MDSC function has come from studies involving cancer models, however many recent studies have helped to characterize MDSC involvement in autoimmune diseases. MDSCs are a heterogeneous group of immature myeloid cells with a number of different functions for the suppression of T cell responses. However, we have yet to fully understand their contributions to the development and regulation of autoimmune diseases. A number of studies have described beneficial functions of MDSCs during autoimmune diseases, and thus there appears to be a potential role for MDSCs in the treatment of these diseases. Nevertheless, many questions remain as to the activation, differentiation, and inhibitory functions of MDSCs. This review aims to summarize our current knowledge of MDSC subsets and suppressive functions in tissue-specific autoimmune disorders. We also describe the potential of MDSC-basedcell therapy for the treatment of autoimmune diseases and note some of hurdles facing the implementation of this therapy.
基金supported by grants from the Foundation of Science and Technology of Wuhan City(No.201161038339)Health Department of Hubei Province of China(No.QJX2010-4)+1 种基金Natural Science Foundation of Hubei Province of China(No.2011CDB205)National"Twelfth Five-Year"Plan for Science&Technology Support(No.2012BAI11B00)
文摘Myeloid-derived suppressor cells （MDSCs） play a crucial role in T cell dysfunction, which is related to poor outcome in patients with severe trauma. Cyclooxygenase-2 （Cox-2） contributes to immune disorder in trauma and infection via production of prostaglandin E2. However, the role of Cox-2 in the accumulation and function of MDSCs after traumatic stress has not been fully elucidated. In the present study, we treated murine trauma model with NS398, a selective Cox-2 inhibitor. Then the percentages of CD1 lb＋/Gr-l＋ cells, proliferation and apoptosis of CD4＋ T cells were determined. Ar- ginase activity and arginase-1 （Arg-1） protein expression of splenic CDllb＋/Gr-I＋ cells, and de- layed-type hypersensitivity （DTH） response were analyzed. The results showed that Cox-2 blockade significantly decreased the percentages of CD1 lb＋/Gr-l＋ cells in the spleen and bone marrow 48 and 72 h after traumatic stress. NS398 inhibited arginase activity and down-regulated the Arg-1 expression of splenic CD1 lb＋/Gr-l＋ ceils. Moreover, NS398 could promote proliferation and inhibit apoptosis of CD4＋ T cells. It also restored DTH response of traumatic mice. Taken together, our data revealed that Cox-2 might play a pivotal role in the accumulation and function of MDSC after traumatic stress.
基金Supported by Grants from the Natural Science Foundation of China, No. 30872335, 81172871The Natural Science Foundation of Jiangsu Province, No. BK2009208the Jiangsu Government Scholarship for Overseas Studies
文摘AIM: To perform a comprehensive investigation into the potential correlation between circulating myeloidderived suppressor cells (MDSCs) and Th17 cells in esophageal cancer (ECA). METHODS: A total of 31 patients newly diagnosed with ECA and 26 healthy subjects were included in the current study. The frequencies of MDSCs and Th17 cells in peripheral blood were determined by flow cytometry. The mRNA expression of cytokines, arginase 1 (Arg1) and inducible NO synthase (iNOS) in peripheral blood mononuclear cells (PBMCs) and plasma Arg1 were assessed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: There was an increased prevalence of MDSCs in the peripheral blood from ECA patients (15.21% ± 2.25%) when compared with healthy control (HC) (1.10% ± 0.12%, P < 0.0001). The plasma levels of Arg1 in ECA patients were significantly higher than those in HC (28.28 ± 4.10 ng/mL vs 9.57 ± 1.51 ng/ mL, P=0.0003). iNOS mRNA levels in the peripheral blood of ECA patients also showed a threefold increase compared with HC (P=0.0162). The frequencies of Th17 cells (CD4 + IL-17A + ) were significantly elevated in ECA patients versus HC (3.50% ± 0.33% vs 1.82% ± 0.19%, P=0.0001). Increased mRNA expression of IL-17 and ROR-γt was also observed in ECA patients compared with HC (P=0.0041 and P=0.0004, respectively), while the mRNA expression of IL-6 and tumor necrosis factor-α (TNF-α) showed significant decreases (P=0.0049 and P < 0.0001, respectively). No obvious correlations were found between the frequencies of MDSCs and Th17 cells in the peripheral blood from ECA patients(r=-0.1725, P=0.3534). Arg1 mRNA levels were positively correlated with levels of IL-6 (r=0.6404, P=0.0031) and TNF-α (r=0.7646, P=0.0001). Similarly, iNOS mRNA levels were also positively correlated with levels of IL-6 (r=0.6782, P=0.0007) and TNF-α (r=0.7633, P < 0.0001). CONCLUSION: This study reveals the relationship between circulating MDSCs and Th17 cells, which may lead to new immunotherapy approaches for ECA based on the associated metabolites and cytokines.
基金Supported by a grant from National Natural Science Foundation of China(grant number 81571783)National Major Project for Infectious Diseases of China(2017ZX100203205005)
文摘Purpose: A series of clinical studies have established the safety and efficacy of transcatheter arterial chemoembolization(TACE) with gelatin sponge microparticles(GSMs) in treating hepatocellular carcinoma(HCC). HCC can lead to obvious necrosis inside tumors, especially larger ones, although it is unclear whether such necrotic tumor tissue can induce favorable immune reactions against the tumor. Myeloid-derived suppressor cells(MDSCs)have immunosuppressive functions and are currently considered a very important cell type affecting tumor immunity. This study observed changes in MDSC frequency in peripheral blood before and after GSM–TACE to evaluate the effect on the immune function of HCC patients.Methods: Eight patients diagnosed with HCC underwent GSM–TACE treatment in the Hepatobiliary Interventional Department of Beijing Tsinghua Chang Gung Hospital, Beijing, China;we followed up with the patients over a period of 30 days post-surgery. We used flow cytometry(FCM) to quantify the frequency of MDSCs in peripheral blood before TACE, 10 days after surgery and 30 days after surgery.Results: MDSC frequency after GSM–TACE had a significant downward trend. Pre-TACE, it was 30.73% ? 11.93%,decreasing to 18.60% ? 11.37% at 10 days after operation. This decrease was not statistically significant(P > 0.05). MDSC frequency was even lower 30 days after TACE(7.63% ? 7.32%) than at 10 days after TACE(P < 0.05), and there was a significant difference compared with pre-TACE(P < 0.001). We evaluated tumor response at 30 days after GSM–TACE according to the Modified Response Evaluation Criteria in Solid Tumors(mRECIST), and all eight patients showed partial response(PR).Conclusion: Our results confirmed that GSM–TACE was beneficial for improving anti-tumor immunity in the treatment of HCC.
基金supported by grants from Department of Health of Hubei Province(No.JX5B07)Department of Health of Wuhan(No.WX09B02)
文摘The effects of granulocyte colony-stimulation-factor （G-CSF） on stem cell mobilization and its impact on the amplification of myeloid-derived suppressor cells （MDSCs） of donor mice were ex- amined. A mouse model of stem cell mobilization was established by consecutive subcutaneous injec- tion of 100 μg/kg G-CSF for 5 days. The blood from the donor mice was routinely examined during mobilization. Stem cells and MDSCs were analyzed by flow cytometry. The immunosuppressive mole- cules derived from MDSCs in serum and spleen, including hydrogen dioxide （H202） and nitric oxide （NO）, and the activity of nitric oxide synthase （NOS） were determined during the mobilization. Apop- tosis of T lymphocytes was assessed by using Annexin-V/PI. During stem cell mobilization, the number of lymphocytes and white blood cells in the peripheral blood was increased, and peaked on the 4th day. The number of stem cells in G-CSF-treated mice was significantly greater than that in controls （P〈0.01）. The expansions of MSDCs were also observed after G-CSF mobilization, with a more notable rate of growth in the peripheral blood than in the spleen. The activity of NOS and the production of NO were increased in the donor mice, and the serum H202 levels were approximately 4-fold greater than the con- trois. Consequently, apoptosis of T lymphocytes was increased and showed a positive correlation with the elevated percentage of MDSCs. It was concluded that G-CSF could provide sufficient peripheral blood stem cells for transplantation. Exogenous administration of G-CSF caused the accumulation of MDSCs in the peripheral blood and the spleen, which could lead to apoptosis ofT lymphocytes and may offer a new strategy for the prevention and treatment of graft versus host disease.
基金supported by the Fundamental Research Funds for the Central Universities(No.2021yjsCXCY086).
文摘Objective Elevated myeloid-derived suppressor cells(MDSCs)in many malignancies are associated with the increased risk for metastases and poor prognosis.Therefore,a mouse model of intraocular melanoma was established to explore how MDSCs influence liver metastases.Methods In this study,murine B16LS melanoma cells were transplanted into the posterior compartment(PC)of the eye of C57BL/6 mice.Leucocytes from the liver of naive mice and mice bearing melanoma liver metastasis were isolated using isotonic Percoll centrifugation,examined by flow cytometry for their expression of Gr1,CD11b,F4/80,RAE-1,and Mult-1,and further isolated for MDSCs and natural killer(NK)cells.The effects of MDSCs on NK cells were tested by coculturing and assessing the ability of NK cells to produce interferon-gamma(IFN-γ)by ELISA and NK cell cytotoxicity by 3H-thymidine incorporation assay.The impact of IFN-γon liver metastases was examined via selectively depleting IFN-γin vivo.Results The results showed that mice with liver metastases had increased levels of CD11b+Gr1+F4/80+as well as CD11b+Gr1+F4/80−MDSCs.MDSCs significantly enhanced the generation of IFN-γtogether with the cytotoxicity of the NK cells.Furthermore,these effects were cell-cell contact-dependent.Although IFN-γwas not of a toxic nature to the melanoma cells,it profoundly inhibited B16LS cell proliferation.Depleting IFN-γin vivo led to increased liver metastases.Conclusion All these findings first revealed that MDSCs accumulated in liver metastasis of intraocular melanoma could activate the NK cells to produce an effective anti-tumor immune response.Thus,the MDSCs’performance in different tumor models would need more investigation to boost current immunotherapy modalities.
文摘Gastrointestinal(GI)cancers are one of the most common malignancies worldwide,with high rates of morbidity and mortality.Myeloid-derived suppressor cells(MDSCs)are major components of the tumor microenvironment(TME).MDSCs facilitate the transformation of premalignant cells and play roles in tumor growth and metastasis.Moreover,in patients with GI malignancies,MDSCs can lead to the suppression of T cells and natural killer cells.Accordingly,a better understanding of the role and mechanism of action of MDSCs in the TME will aid in the development of novel immune-targeted therapies.
基金Supported by National Institutes of Health,No.CA138759,CA152099,to Yan CHL087001,to Du H,and HL-061803 and HL-067862 to Yan C and Du H
文摘Lysosomal acid lipase （LAL） cleaves cholesteryl esters （CE） and triglycerides （TG） to generate cholesterol and free fatty acid in lysosomes of cells. The down-stream metabolic products of fatty acids are ligands for activation of peroxisome proliferator-activated re-ceptor gamma （PPARγ）. Accumulation of CEs and TGs is resulted from lack of functional LAL in lysosomes of cells, especially in myeloid cells. One characteristic phenotype in LAL knock-out （ lal-/- ） mice is systemic elevation of myeloid-derived suppressive cells （MDSCs）. MDSCs infltrate into multiple distal organs, alter T cell development, and suppress T cell proliferation and lym-phokine production in lal-/- mice, which lead to severe pathogeneses in multiple organs. The gene transcrip-tional profle analysis in MDSCs from the bone marrow has identified multiple defects responsible for MDSCs malformation and malfunction in lal-/- mice, including G protein signaling, cell cycles, glycolysis metabolism, mitochondrial bioenergetics, mTOR pathway etc. In a sep-arate gene transcriptional profle analysis in the lung of lal-/- mice, matrix metalloproteinase 12 （MMP12） and apoptosis inhibitor 6 （Api6） are highly overexpressed due to lack of ligand synthesis for PPARγ. PPARγ nega-tively regulates MMP12 and Api6. Blocking the PPAR signaling by overexpression of a dominant negative PPARγ （dnPPARγ） form, or overexpressing MMP12 or Api6 in myeloid or lung epithelial cells in inducible transgenic mouse models results in elevated MDSCs and infammation-induced tumorigenesis. These stud-ies demonstrate that LAL and its downstream effectors are critical for MDSCs development, differentiation and malfunction.
文摘Cancer vaccines to date have not broadly achieved a significant impact on the overall survival of patients. The negative effect on the immune system of the tu-mor itself and conventional anti-tumor treatments such as chemotherapy is, undoubtedly, a key reason for these disappointing results. Myeloid-derived suppres-sor cells （MDSCs） are considered a central node of the immunosuppressive network associated with tumors. These cells inhibit the effector function of natural killer and CD8＋ T cells, expand regulatory T cells and can differentiate into tumor-associated macrophages within the tumor microenvironment. Thus, overcoming the suppressive effects of MDSCs is likely to be criti-cal for cancer immunotherapy to generate effective anti-tumor immune responses. However, the capacity of cancer vaccines and particularly their adjuvants to overcome this inhibitory population has not been well characterized. Very small size proteoliposomes （VSSP） is a nanoparticulated adjuvant specifcally designed to be formulated with vaccines used in the treatment of immunocompromised patients. This adjuvant contains immunostimulatory bacterial signals together with GM3 ganglioside. VSSP promotes dendritic cell maturation, antigen cross-presentation to CD8＋ T cells, Th1 polar-ization, and enhances CD8＋ T cell response in tumor-free mice. Currently, four cancer vaccines using VSSP as the adjuvant are in Phase？Ⅰ？and Ⅱ clinical trials. In this review, we summarize our work characterizing the unique ability of VSSP to stimulate antigen-specifc CD8＋ T cell responses in two immunocompromised sce-narios; in tumor-bearing mice and during chemother-apy-induced leukopenia. Particular emphasis has been placed on the interaction of these nanoparticles with MDSCs, as well as comparison with other cancer vac-cine adjuvants currently in preclinical or clinical studies.
基金supported by National Key R&D Program of China(No.2019YFE0111800)National Natural Science Foundation of China(Nos.T2192972,81872923,and 81903904)the CAMS Innovation Fund(2022-I2M-1-014,China).
文摘Glioblastoma(GBM)is a highly aggressive and lethal brain tumor with an immunosuppressive tumor microenvironment(TME).In this environment,myeloid cells,such as myeloid-derived suppressor cells(MDSCs),play a pivotal role in suppressing antitumor immunity.Lipometabolism is closely related to the function of myeloid cells.Here,our study reports that acetyl-CoA acetyltransferase 1(ACAT1),the key enzyme of fatty acid oxidation(FAO)and ketogenesis,is significantly downregulated in the MDSCs infiltrated in GBM patients.To investigate the effects of ACAT1 on myeloid cells,we generated mice with myeloid-specific(LyzM-cre)depletion of ACAT1.The results show that these mice exhibited a remarkable accumulation of MDSCs and increased tumor progression both ectopically and orthotopically.The mechanism behind this effect is elevated secretion of C-X-C motif ligand 1(CXCLI)of macrophages(Mo).Overall,our findings demonstrate that ACAT1 could serve as a promising drug target for GBM by regulating the function of MDSCs in the TME.
基金supported by the National Basic Research Program of China (973 Program) (No 2010CB529403)the National Natural Science Foundation of China (Nos 30725035 and 30930103)
文摘Growing evidence suggests that myeloid-derived suppressor cells （MDSCs）,which have been named ＂immature myeloid cells＂ or ＂myeloid suppressor cells＂ （MSCs）,play a critical role during the progression of cancer in tumor-bearing mice and cancer patients.As their name implies,these cells are derived from bone marrow and have a tremendous potential to suppress immune responses.Recent studies indicated that these cells also have a crucial role in tumor progression.MDSCs can directly incorporate into tumor endothelium.They secret many pro-angiogenic factors as well.In addition,they play an essential role in cancer invasion and metastasis through inducing the production of matrix metalloproteinases （MMPs）,chemoattractants and creating a pre-metastatic environment.Increasing evidence supports the idea that cancer stem cells （CSCs） are responsible for tumorigenesis,resistance to therapies,invasion and metastasis.Here,we hypothesize that CSCs may ＂hijack＂ MDSCs for use as alternative niche cells,leading to the maintenance of stemness and enhanced chemo-and radio-therapy resistance.The countermeasure that directly targets to MDSCs may be useful for against angiogenesis and preventing cancer from invasion and metastasis.Therefore,the study of MDSCs is important to understand tumor progression and to enhance the therapeutic efficacy against cancer.
基金Science Foundation of China （No. 81272075）, Zhejiang Provincial Natural Science Foundation of China （No. Y2100430）, and the Zhejiang Provincial Education and Research Foundation of China （No. Y201019154）.
文摘Background Hemorrhagic shock is usually associated with complicated immune and inflammatory responses, which are sometimes crucial for the prognosis. As regulators of the immune and inflammatory system; proliferation, migration, distribution and activation of myeloid-derived suppressor cells （MDSCs） are intimately linked to the inflammation cascade. Methods In a model of severe hemorrhagic shock, thirty-five rats were randomly divided into control, sham, normal saline resuscitation （NS）, hypertonic saline resuscitation （HTS）, and hydroxyethyl starch resuscitation （HES）, with seven in each group. MDSCs were analyzed by flow cytometric staining of CD11b/c＊Gra~ in peripheral blood mononuclear cells （PBMC）, spleen cell suspensions, and bone marrow nucleated cells （BMNC）. Simultaneously, the expressions of arginase-1 （ARG-1） and inducible nitric oxide synthase （iNOS） mRNA in MDSCs were evaluated by quantitative reverse transcription-polymerase chain reaction （qRT-PCR）. Results In the early stage after hemorrhagic shock, fluid resuscitation and emergency treatment, the MDSCs in the PBMC of NS, HTS and HES groups markedly increased, and MDSCs in BMNC of these groups decreased accordingly, significantly different to the control group. In hemorrhagic shock rats infused with HTS at the early resuscitation stage, MDSCs in PBMC increased about 2 and 4 folds, and MDSCs in BMNC decreased about 1.3 and 1.6 folds, as compared to the sham group respectively, with statistically significant difference. Furthermore, compared to the NS and HES groups, the MDSCs in PBMC of HTS group increased 1.6 and 1.8 folds with statistically significant differences; the MDSCs decrease in BMNC was not significant. However, there was no statistically significant difference in MDSCs of spleen among the five groups. In addition, compared to the control, sham, NS and HES groups, the ARG-1 and iNOS mRNA of MDSCs in PBMC, spleen and BMNC in the HTS group had the highest level of expression, but no statistically significant differences were noted. Conclusions In this model of rat with severe and controlled hemorrhagic shock, small volume resuscitation with HTS contributes to dramatically early migration and redistribution of MDSCs from bone marrow to peripheral circulation, compared to resuscitation with NS or HES.
基金Supported by the National Natural Science Foundation of China(No.81273946 and No.81072802)the National Science and Technology Major Projects for"Major New Drugs Innovation and Development"(No.2013ZX09303301)
文摘Objective： To observe the intervention effect of Shugan Jianpi Formula （疏肝健脾方,SGJPF） on a breast cancer mouse model with depression and investigate the underlying mechanism of SGJPF in preventing the development of breast cancer. Metkods： The breast cancer model was induced by inoculation of breast cancer cells, the depression model was induced by chronic stress stimuli, and the depression cancer model was established by combining the two factors. The mice were divided into 7 groups： normal control, depression model, tumor model, depression tumor model, SGJPF, chemotherapy, and SGJPF＋chemotherapy groups. The last 3 groups were depression breast cancer mice and treated respectively with SGJPF, chemotherapy drug gemcitabine （GEM）, and SGJPF alongside GEM. The condition of the mice was evaluated by the expression of 5-hydroxytryptamine in hippocampus after the sucrose water test and open field test, weight change, and survival time. Tumor growth was monitored with in vivo imaging. Flow cytometry was used to analyze the level of myeloid-derived suppression cell （MDSC） in the mouse spleen, T cell subsets, and the early apoptosis of CD8~ T cells, Results： The SGJPF＋GEM group had the highest inhibition rate and the longest survival time （P〈0.01）. The MDSC level and the apoptosis rate of CD8＊ T cells was the highest in the SGJPF＋GEM group （P〈0.05）. Conclusions： Depressive disorders and tumor growth could suppress the immune function of mice to different degrees, and the microenvironment in late 4T1 inflammatory breast cancer may play an important role in the pathological process. SGJYF could regulate the immune microenvironment by reducing CD8＊ T lymphocyte apoptosis and tumor cell activity, increasing immune surveillance capability, and inhibiting MDSC proliferation, thus prolonging the survival time of tumor-bearing mice.
文摘In recent years,studying the role of myeloid-derived suppressor cells(MDSCs)in many pathological inflammatory conditions has become a very active research area.Although the role of MDSCs in cancer is relatively well established,their role in non-cancerous pathological conditions remains in its infancy resulting in much confusion.Our objectives in this review are to address some recent advances in MDSC research in order to minimize such confusion and to provide an insight into their function in the context of other diseases.The following topics will be specifically focused upon:(1)definition and characterization of MDSCs;(2)whether all MDSC populations consist of immature cells;(3)technical issues in MDSC isolation,estimation and characterization;(4)the origin of MDSCs and their anatomical distribution in health and disease;(5)mediators of MDSC expansion and accumulation;(6)factors that determine the expansion of one MDSC population over the other;(7)the Yin and Yang roles of MDSCs.Moreover,the functions of MDSCs will be addressed throughout the text.
基金This work was supported by grants from the National Natural Science Foundation of China(Nos.81900121,81770133,81973994,and 81770114)Major Research Plan of National Natural Science Foundation of China(No.91942306)+3 种基金Clinical Research Center of Shandong University(No.2020SDUCRCC009)Graduate Education Reform Project of Shandong University(No.XYJG2020141)State Key Clinical Specialty of China for Blood DisordersYoung Taishan Scholar Foundation of Shandong Province(No.tsqn201909175).
文摘Myeloid-derived suppressor cells(MDSCs)are a heterogeneous population of immature cells and natural inhibitors of adaptive immunity.Intracellular metabolic changes in MDSCs exert a direct immunological influence on their suppressive activity.Our previous study demonstrated that high-dose dexamethasone(HD-DXM)corrected the functional impairment of MDSCs in immune thrombocytopenia(ITP);however,the MDSC population was not restored in nonresponders,and the mechanism remained unclear.In this study,altered mitochondrial physiology and reduced mitochondrial gene transcription were detected in MDSCs from HD-DXM nonresponders,accompanied by decreased levels of carnitine palmitoyltransferase-1(CPT-1),a rate-limiting enzyme in fatty acid oxidation(FAO).Blockade of FAO with a CPT-1 inhibitor abolished the immunosuppressive function of MDSCs in HD-DXM responders.We also report that MDSCs from ITP patients had lower expression of the glucocorticoid receptor(GR),which can translocate into mitochondria to regulate the transcription of mitochondrial DNA(mtDNA)as well as the level of oxidative phosphorylation.It was confirmed that the expression of CPT-1 and mtDNA-encoded genes was downregulated in GR-siRNA-treated murine MDSCs.Finally,by establishing murine models of active and passive ITP via adoptive transfer of DXM-modulated MDSCs,we confirmed that GR-silenced MDSCs failed to alleviate thrombocytopenia in mice with ITP.In conclusion,our study indicated that impaired aerobic metabolism in MDSCs participates in the pathogenesis of glucocorticoid resistance in ITP and that intact control of MDSC metabolism by GR contributes to the homeostatic regulation of immunosuppressive cell function.
基金This study was partly supported by the National Natural Science Foundation of China （No. 81170472）, the Application Bases and Advanced Technology Research Program of Tianjin （No. 09JCYBJC11200）, the Special Fund for Health-Scientific Research in the Public Interest （No. 201202017）, the Medical Scientific Research Foundation of Tianjin （No. 2012KZ103）, and the Special Anticancer Fund of Scientific Planning Project of Tianjin （No. 12ZCDZSY 17900）.
文摘Myelodysplastic syndrome （MDS） is a group of clonal .hematopoietic stem cell disorders, characterizedby varying degrees ot peripheral cytopema caused by ineffective dysplasia of the myeloid lineages. MDS also has a high risk of progression to acute myeloid leukemia. But the role of immune abnormalities in the pathogenesis of MDS is still not clear. Myeloid-derived suppressor cells （MDSCs） constitute a heterogeneous population of immature cells derived from the bone marrow. In the recent years, MDSCs were reported to play an important role in suppressing lymphocytes in tumor-bearing animal models and cancer patients. This could be one of the mechanisms on tumor immune evasion, which aggravates the development and growth of tumors. In a mice model, MDSCs are characterized by co- expression of GR1 and CDllb. In humans, the phenotype of MDSCs was accepted as Lin- HLA-DR- CD33＋.l In the present study, we investigated the level of circulating MDSCs （Lin- HLA-DR- CD33＋） in patients with MDS and evaluated the association between MDSCs and malignancy in MDS. METHODS Patients Thirty-five patients with MDS （24 men and 11 women, median age 59 years （age range 21-83）, including refractory anemia （n=3）; refractory anemia with ringed sideroblasts （n=3）; refractory cytopenia with multilineage dysplasia （n=9）; refractory anemia with excess blast-I （n=4）; refractory anemia with excess blast-II （n=16））, and without other systemic diseases, were enrolled in the present study. All the patients underwent diagnosis in the Department of Hematology, General Hospital of Tianjin Medical University from March 2011 to April 2012, according to the diagnostic criteria of MDS proposed between 2007 and 2008. After treatment for three months, 14 MDS patients were investigated again for their MDSCs changes. Twenty normal healthy individuals were selected as controls （9 men and 11 women, median age 34 years （age range 26-82））. The study was approved by the Ethics Committee of Tianjin Medical University. Informed written consent was obtained from all the patients and normalindividuals in accordance with the Declaration of Helsinki Flow cytometric analysis Peripheral blood samples were collected in EDTA- anticoagulant tubes from the patients and normal individuals. The number of circulating MDSCs was measured by using flow cytometry （FCM） assay. The markers used in the assay were anti-CD33-APC, anti-LIN- FITC （CD3, CD14, CD16, CD19, CD20, CD56） and anti- HLA-DR-PE antibodies （BD Biosciences, USA）. The number of stem cells from the bone marrow, which was collected in heparin-anticoagulant tubes, was measured by FCM using anti-CD34-PerCP antibodies （BD Biosciences）. Data acquisition and analysis were carried out by using FACS-Calibur flow cytometer （BD Biosciences）, with the Cell Quest software （Becton Dickinson, version 3.1）.
基金This research is supported by grants from the National Natural Science Foundation for General Programs of China(31671524,31171407 and 81273201,GL)the Key Basic Research Project of the Science and Technology Commission of Shanghai Municipality(12JC1400900,GL)+2 种基金the Innovation Program of Shanghai Municipal Education Commission(14ZZ009,GL)the Excellent Youth Foundation of Chinese Academy of Sciences(KSCX2-EW-Q-7,GL)R21AI117547,1R01AI114581,V2014-001 from the V-foundation,and 128436-RSG-15-180-01-LIB from the American Cancer Society(RW).
文摘Immunomodulatory signaling imposes tight regulations on metabolic programs within immune cells and consequentially determines immune response outcomes.Although the glucocorticoid receptor(GR)has been recently implicated in regulating the function of myeloid-derived suppressor cells(MDSCs),whether the dysregulation of GR in MDSCs is involved in immune-mediated hepatic diseases and how GR regulates the function of MDSCs in such a context remains unknown.Here,we revealed the dysregulation of GR expression in MDSCs during innate immunological hepatic injury(IMH)and found that GR regulates the function of MDSCs through modulating HIF1α-dependent glycolysis.Pharmacological modulation of GR by its agonist(dexamethasone,Dex)protects IMH mice against inflammatory injury.Mechanistically,GR signaling suppresses HIF1αand HIF1α-dependent glycolysis in MDSCs and thus promotes the immune suppressive activity of MDSCs.Our studies reveal a role of GR-HIF1αin regulating the metabolism and function of MDSCs and further implicate MDSC GR signaling as a potential therapeutic target in hepatic diseases that are driven by innate immune cell-mediated systemic inflammation.
