NEDD9 promotes cancer stemness by recruiting myeloid-derived suppressor cells via CXCL8 in esophageal squamous cell carcinoma

Objective:Esophageal squamous cell carcinoma(ESCC)has high morbidity and mortality rates worldwide.Cancer stem cells(CSCs)may cause tumor initiation,metastasis,and recurrence and are also responsible for chemotherapy and radiotherapy failures.Myeloid-derived suppressor cells(MDSCs),in contrast,are known to be involved in mediating immunosuppression.Here,we aimed to investigate the mechanisms of interaction of CSCs and MDSCs in the tumor microenvironment.Methods:ESCC tissues and cell lines were evaluated.Neural precursor cell expressed,developmentally downregulated 9(NEDD9)was knocked down and overexpressed by lentiviral transfection.Quantitative PCR,Western blot,immunohistochemistry,cell invasion,flow cytometry,cell sorting,multiplex chemokine profiling,and tumor growth analyses were performed.Results:Microarray analysis revealed 10 upregulated genes in esophageal CSCs.Only NEDD9 was upregulated in CSCs using the sphere-forming method.NEDD9 expression was correlated with tumor invasion(P=0.0218),differentiation(P=0.0153),and poor prognosis(P=0.0373).Additionally,NEDD9 was required to maintain the stem-like phenotype.Screening of chemokine expression in ESCC cells with NEDD9 overexpression and knockdown showed that NEDD9 regulated C-X-C motif chemokine ligand 8(CXCL8)expression via the ERK pathway.CXCL8 mediated the recruitment of MDSCs induced by NEDD9 in vitro and in vivo.MDSCs promoted the stemness of ESCC cells through NEDD9 via the Notch pathway.Conclusions:As a marker of ESCC,NEDD9 maintained the stemness of ESCC cells and regulated CXCL8 through the ERK pathway to recruit MDSCs into the tumor,suggesting NEDD9 as a therapeutic target and novel prognostic marker for ESCC.

Circulating myeloid-derived suppressor cells in patients with pancreatic cancer

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.

Cyclooxygenase-2 Blockade Inhibits Accumulation and Function of Myeloid-derived Suppressor Cells and Restores T Cell Response after Traumatic Stress

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.

Amplification of Functional Myeloid-derived Suppressor Cells during Stem Cell Mobilization Induced by Granulocyte Colony-stimulation-factor

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.

Changes in the frequency of myeloid-derived suppressor cells after transarterial chemoembolization with gelatin sponge microparticles for hepatocellular carcinoma

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.

GM3-containing nanoparticles in immunosuppressed hosts:Effect on myeloid-derived suppressor cells

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.

Emerging roles of myeloid derived suppressor cells in hepatic inflammation and fibrosis

Myeloid derived suppressor cells(MDSC) are a heterogeneous population of immune cells that are potent suppressors of immune responses. MDSC emerge in various compartments in the body, such as blood, bonemarrow or spleen, especially in conditions of cancer, infections or inflammation. MDSC usually express CD11 b, CD33, and low levels of human leukocyte antigen-DR in humans or CD11 b and Gr1(Ly6C/G) in mice, and they can be further divided into granulocytic or monocytic MDSC. The liver is an important organ for MDSC induction and accumulation in hepatic as well as extrahepatic diseases. Different hepatic cells, especially hepatic stellate cells, as well as liver-derived soluble factors, including hepatocyte growth factor and acute phase proteins(SAA, KC), can promote the differentiation of MDSC from myeloid cells. Importantly, hepatic myeloid cells like neutrophils, monocytes and macrophages fulfill essential roles in acute and chronic liver diseases. Recent data from patients with liver diseases and animal models linked MDSC to the pathogenesis of hepatic inflammation, fibrosis and hepatocellular carcinoma(HCC). In settings of acute hepatitis, MDSC can limit immunogenic T cell responses and subsequent tissue injury. In patients with chronic hepatitis C, MDSC increase and may favor viral persistence. Animal models of chronic liver injury, however, have not yet conclusively clarified the involvement of MDSC for hepatic fibrosis. In human HCC and mouse models of liver cancer, MDSC are induced in the tumor environment and suppress anti-tumoral immune responses. Thus, the liver is a primary site of MDSC in vivo, and modulating MDSC functionality might represent a promising novel therapeutic target for liver diseases.

Effects of methionine enkephalin on immune enhancement by reducing myeloid derived suppressor cells and reprogramming liver metabolism in colon cancer mice

OBJECTIVE To investigate enhanced immune function of methionine encephalin(MENK)and its anti-tumor mechanism in CT26 colon cancer mouse model.METHODS 3×10~6CT26 cells were implanted subcutaneously in BALB/c mice.Four days after,MENK was peritoneally administrated at the concentration of 20 mg·kg^(-1) for 14 d.The percentage of MDSCs in bone marrow,spleen,blood,tumor and liver were detected by flow cytometry.Non-esterified fatty acid(NEFA),triglycerides(TG)and total cholesterol(T-CHO)in liver homogenate were tested by a NEFA test kit,a TG test kit and a T-CHO test kit respectively.qRT-PCR and Western blot were used to measure m RNA and protein levels of inflammation-,glycometabolsim-and lipometabolsim-associated indexes in liver.RESULTS MENK decreased percentages of MDSCs in bone marrow,spleen,blood and tumor in colon cancer mice.MENK-treated mice displayed elevated ratio of CD4^+T and CD8^+T cells in spleen as well as increased T and B lymphocytes proliferation.Meanwhile,MENK also ameliorated liver damage reflected by lower levels of GPT and GOT in serum and reduced risks of cancer-associated index including inflammation,high lipid and high glucose.Furthermore,MENK lowered down the levels of NEFA,TG and T-CHO in liver homogenate.MENK treatment decreased expression of p-STAT3,increased expression of p-AKT,IRS1 and Glut4 at protein level as well as reduced lipogenesis-associated genes and elevated glycolysis-associated genes in liver of tumor bearing mice.Also,abated expression of genes associated with MDSCs generation(M-CSF,GM-CSF,IL-6,IL^(-1)β)and migration(S100A9,KC)was observed within shrunken subcutaneous tumor by MENK intervention.CONCLUSION MENK has the ability to strength immune function against colon cancer by reducing MDSCs and improving liver metabolism.

The protective role of myeloid-derived suppressor cells in concanavalin A-induced hepatic injury

The mechanism underlying T cell-mediated fulminant hepatitis is not fully understood. In this study, we investigated whether myeloid derived suppressor cells （MDSCs） could prevent the concanavalin A （ConA）- induced hepatitis through suppressing T cell proliferation. We observed an increase in the frequencies of MDSCs in mouse spleen and liver at early stage of ConA treatment, implicating that the MDSCs might be involved in the initial resistance of mice against ConA- mediated inflammation. Subpopulation analysis showed that the MDSCs in liver of ConA-induced mice were mainly granulocytic MDSCs. Adoptive transfer of the bone marrow-derived MDSCs into ConA-treated mice showed that the MDSCs migrated into the liver and spleen where they suppressed T cell proliferation through ROS pathway. In addition, the frequencies of MDSCs in mice were also significantly increased by the treatment with immune suppressor glucocorticoids. Transfer of MDSCs into the regulatory T cell （Treg）- depleted mice showed that the protective effect of MDSCs on ConA-induced hepatitis is Treg-independent. In conclusion, our results demonstrate that MDSCs possess a direct protective role in T cell-mediated hepatitis, and increasing the frequency of MDSCs by either adoptive transfer or glucocorticoid treatment represents a potential cell-based therapeutic strategy for the acute inflammatory disease.

Hepatic immune tolerance induced by hepatic stellate cells

The liver, which is a metabolic organ, plays a pivotal role in tolerance induction. Hepatic stellate cells(Hp SCs), which are unique non-parenchymal cells, exert potent immunoregulatory activity during cotransplantation with allogeneic islets effectively protecting the islet allografts from rejection. Multiple mechanisms participate in the immune tolerance induced by Hp SCs, including the marked expansion of myeloid-derived suppressor cells(MDSCs), attenuation of effector T cell functions and augmentation of regulatory T cells. Hp SC conditioned MDSC-based immunotherapy has been conducted in mice with autoimmune disease and the results show that this technique may be promising. This article demonstrates how Hp SCs orchestrate both innate immunity and adaptive immunity to build a negative network that leads to immune tolerance.

Contribution of myeloid-derived suppressor cells to tumor-induced immune suppression,angiogenesis,invasion and metastasis

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.

Increased circulating of myeloid-derived suppressor cells in myelodysplastic syndrome

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）.

Hypertonic saline resuscitation contributes to early accumulation of circulating myeloid-derived suppressor cells in a rat model of hemorrhagic shock

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.

西黄丸抑制乳腺癌4T1荷瘤小鼠生长的作用及其机制

目的:观察西黄丸抑制4T1荷瘤小鼠生长的作用及其免疫调控机制。方法:建立4T1小鼠乳腺癌模型,观察不同剂量西黄丸干预对肿瘤生长的抑制作用;流式细胞仪检测荷瘤小鼠外周血、脾脏、骨髓来源免疫抑制细胞(myeloid-derived suppressor cells,MDSCs)比例,同时分离小鼠脾脏检测活性氧(reactive oxygen species,ROS)、CD3+T、CD8+T、CD8+T IFN-γ+细胞所占的比例;Luminex液相芯片技术检测荷瘤小鼠外周血白细胞介素-1β(interleukin-1β,IL-1β)、白细胞介素-6(interleukin-6,IL-6)、单核细胞趋化因子-1(monocyte chemoattractant protein-1,MCP-1)的含量。结果:西黄丸0.9、0.6、0.3 g/kg各剂量治疗组均显示了一定的抑制肿瘤生长的作用(P<0.01或P<0.05),其中以0.9 g/kg组抑制作用最为明显,抑瘤率达到40%。西黄丸可减少荷瘤小鼠外周血、骨髓、脾脏MDSCs比例以及脾脏细胞ROS水平,提高脾脏细胞CD3+T细胞、CD8+T以及CD8+T IFN-γ+细胞所占的比例,同时,西黄丸可显著减少小鼠外周血MDSCs生成密切相关细胞因子IL-6、IL-1β的表达。结论:西黄丸可通过减少MDSCs比例,增强荷瘤小鼠抗肿瘤免疫功能抑制小鼠4T1炎性乳腺癌的生长,降低IL-6、IL-1β可能是其调控MDSCs的机制之一,对于其深入的作用机制还需要进一步的探索。

髓源性抑制细胞相关抗原在垂体瘤中的表达

目的:探讨髓源性抑制细胞(myeloid-derived suppressor cells,MDSCs)相关抗原在垂体瘤中的表达。方法:选取2012—2022年在汕头大学医学院第二附属医院就诊的垂体瘤患者26例(垂体瘤组),其中侵袭性垂体瘤16例,非侵袭性垂体瘤10例。另外收集同期10例需行内减压术的颅脑外伤或脑出血患者为对照组。垂体瘤组男性19例,女性7例,平均年龄(52±18)岁。对照组男性7例,女性3例,平均年龄(51±19)岁。采用免疫荧光染色的方法,分别检测垂体瘤患者肿瘤组织和对照组患者脑组织中MDSCs相关抗原CD11b、CD15和IL-4Rα的表达情况。结果:垂体瘤中CD11b^(+)、CD15^(+)、CD11b^(+)CD15^(+)髓源性粒细胞的荧光强度均高于对照组,差异有统计学意义(均P<0.05)。在侵袭性垂体瘤组织中CD11b^(+)、CD15^(+)、CD11b^(+)CD15^(+)髓源性粒细胞的荧光强度均高于非侵袭性组(均P<0.05)。IL-4Rα在垂体瘤和脑组织中均未见表达。结论:MDSCs相关抗原CD11b、CD15及CD11b^(+)CD15^(+)髓源性粒细胞在垂体瘤(特别是侵袭性垂体瘤)中的表达水平升高。

23-羟基白桦酸通过抑制髓源性抑制细胞对小鼠结肠癌生长的影响

目的探讨23-羟基白桦酸(23-HBA)通过干预髓源性抑制细胞(MDSCs)抑制小鼠结肠癌生长的作用机制。方法体内实验,建立小鼠结肠癌CT-26皮下移植瘤模型,阳性对照组5-FU腹腔注射3 d(2次),实验组23-HBA尾静脉每日注射,连续给药18 d。末次给药后处死小鼠,检测小鼠体质量、移植瘤质量及体积、脏器指数、血常规的变化,流式细胞术检测肿瘤组织MDSCs、CD8^(+)T细胞比例,RT-qPCR法检测肿瘤组织MDSCs细胞免疫抑制功能相关细胞因子精氨酸酶1(Arg1)、一氧化氮合酶(iNOS),以及CD8^(+)T细胞杀伤功能相关细胞因子颗粒酶B(GZMB)、穿孔素1(PRF1)、干扰素-γ(IFN-γ)mRNA的表达。体外实验,CCK8法检测骨髓(BM)细胞、MDSCs细胞存活率,确定23-HBA的安全作用浓度;采用40 ng/mL粒细胞-巨噬细胞集落刺激因子(GM-CSF)和40 ng/mL白细胞介素-6(IL-6)诱导BM向MDSCs分化,同时加入不同浓度23-HBA(0、10.5、21、42μmoL/L)干预4 d,流式细胞术检测MDSCs细胞比例变化;BM体外诱导生成MDSCs后,将其分为对照组和23-HBA低、中、高剂量组(10.5、21、42μmoL/L),干预24 h,RT-qPCR法检测MDSCs细胞Arg1、iNOS mRNA表达;Western blot法检测MDSC细胞Arg1、iNOS蛋白表达。结果体内实验显示,与模型组比较,23-HBA干预后,小鼠移植瘤体积及质量均降低(P<0.05,P<0.01);肿瘤组织MDSCs细胞比例降低(P<0.05),CD8^(+)T细胞比例升高(P<0.05,P<0.01),Arg1 mRNA表达降低(P<0.05),GZMB、IFN-γmRNA表达升高(P<0.05,P<0.01)。体外实验显示,23-HBA剂量在10.5、21、42μmoL/L时,对BM、MDSCs细胞存活率没有显著影响(P>0.05);23-HBA高剂量可抑制BM向MDSCs分化(P<0.01);23-HBA呈剂量依赖性减少MDSCs细胞Arg1、iNOS mRNA表达(P<0.05,P<0.01),下调Arg1、iNOS蛋白表达(P<0.05,P<0.01)。结论23-HBA可通过干预MDSCs分化下调肿瘤内MDSCs细胞比例,减弱MDSCs细胞的免疫抑制功能,从而恢复CD8^(+)T细胞抗肿瘤活性,发挥抗结肠癌作用。

乙肝病毒相关慢加急性肝衰竭患者中PMN-MDSC的表达及意义

目的:探讨乙肝病毒相关慢加急性肝衰竭(hepatitis B virus-related acute-on-chronic liver failure,HBV-ACLF)患者中多核型髓源性抑制细胞(polymorphonuclear myeloid-derived suppressor cell,PMN-MDSC)的表达及意义。方法:选取2022年9月—2023年8月皖南医学院弋矶山医院收治的HBV-ACLF患者40例为研究组,同期在该院诊治或体检的慢性乙肝(chronic hepa-titis B,CHB)患者20例、健康对照(healthy control,HC)10例为对照组,收集临床资料,留取血标本。流式细胞术检测入院当日外周血PMN-MDSC频率,比较研究组和两个对照组外周血PMN-MDSC频率的差异。采用Spearman检验分析HBV-ACLF外周血PMN-MDSC频率与炎症指标、疾病严重度的相关性。分别根据是否合并或继发感染及访视期第28天预后情况对HBV-ACLF患者分组,比较各组外周血PMN-MDSC频率的差异。结果:HBV-ACLF组外周血PMN-MDSC频率显著高于CHB组和HC组(P均<0.001),CHB组和HC组之间PMN-MDSC频率差异无统计学意义。HBV-ACLF外周血PMN-MDSC频率与白细胞计数、中性粒细胞淋巴细胞比值、降钙素原水平、国际标准化比值、总胆红素水平、Child-Turcotte-Pugh评分、终末期肝病模型评分均呈正相关(r=0.347、0.799、0.506、0.450、0.462、0.470、0.481,P均<0.05),与淋巴细胞计数呈负相关(r=-0.428,P<0.01)。40例HBV-ACLF患者中,合并感染18例,继发感染17例,28 d预后差21例,其外周血PMN-MDSC频率均高于对照组患者,差异有统计学意义(P均<0.001)。结论:HBV-ACLF患者外周血富集PMN-MDSC,其频率与感染风险、疾病严重度及患者短期预后密切相关。

髓源性抑制细胞在多发性骨髓瘤中的研究进展

多发性骨髓瘤(multiple myeloma,MM)是浆细胞恶性增殖性疾病,目前为血液系统第二大肿瘤。虽然蛋白酶体抑制剂和免疫治疗方案的应用改善了MM患者的预后,但大多数仍然无法被治愈,主要是因为MM细胞最终产生耐药。髓源性抑制细胞(myeloid-derived suppressor cells,MDSCs)是骨髓中髓系祖细胞分化受阻而形成的具有显著抑制T细胞免疫应答功能的一群异质性细胞,通过介导免疫抑制性作用促进MM的发展。MDSCs还刺激MM细胞增殖,诱导MM耐药和转移。本文综述了MDSCs在MM发生、发展中表现的多种机制,并探讨针对MDSCs的治疗策略在MM中的可行性及挑战,以期为MM治疗提供参考。

粒细胞样髓源性抑制细胞在非小细胞肺癌中的研究进展

粒细胞样髓源性抑制细胞(granulocytic myeloid-derived suppressor cells,G-MDSCs)是MDSCs的主要亚群之一,在多数癌症中广泛富集,通过表达精氨酸酶1(arginase-1,Arg-1)及活性氧(reactive oxygen species,ROS)等机制抑制淋巴T细胞杀伤功能,重塑肿瘤免疫微环境,促进肿瘤的发生发展。近年来,越来越多的研究发现G-MDSCs与非小细胞肺癌患者的预后和免疫治疗疗效具有显著相关性,使用特异性靶向G-MDSCs的募集、分化和功能的药物能够有效抑制肿瘤的进展。本文主要就G-MDSCs在非小细胞肺癌中的免疫抑制作用及其相关通路靶向药物的研究进展进行综述。

吡非尼酮联合PD-L1抑制剂抑制小鼠异位膀胱肿瘤的生长

目的通过小鼠肿瘤模型观察吡非尼酮(PFD)联合程序性死亡受体-配体1(PD-L1)抑制剂对膀胱癌的疗效及对免疫微环境的调控作用。方法构建C57BL/6小鼠异位膀胱肿瘤模型共40只,根据不同处理随机分为4组(10只/组):对照组、PD-L1抑制剂组、PFD组、联合治疗组。对照组:建立肿瘤模型正常饮食;PD-L1抑制剂组:建模后腹腔每3 d按12.5 mg/kg注射PD-L1抑制剂;PFD组:建模后每天按500 mg/kg口服PFD;联合治疗组:建模后PFD及PD-L1抑制剂按上述剂量联合应用。对比各组小鼠生存率和肿瘤生长速度,药物干预21 d后留取肿瘤组织及小鼠血清,免疫组化检测肿瘤组织中CD3、CD8、CD45、E-cadherin及N-cadherin的表达;免疫荧光观察骨髓来源抑制细胞(MDSCs)表达;生化分析小鼠血液中谷丙转氨酶(ALT)、谷草转氨酶(AST)、血尿素氮(BUN)、肌酐(CRE)及乳酸脱氢酶(LDH-L)的水平。结果与对照组相比,PD-L1抑制剂组和PFD组小鼠肿瘤相对生长速率及21 d肿瘤体积均减小(P<0.05),联合治疗组小鼠更加显著(P<0.05)。免疫组化及免疫荧光结果显示,PD-L1抑制剂组与PFD组小鼠肿瘤组织E-cadherin表达增加,N-cadherin表达降低(P<0.05)。CD3+T细胞、CD8+T细胞、CD45+T细胞数量较对照组增加,而Ly-6G+CD11b+MDSCs细胞减少,联合组变化更加明显(P<0.05)。生化分析结果显示,各组小鼠血清ALT、AST、BUN、CRE及LDH-L水平无明显差异(P>0.05)。结论吡非尼酮联合PD-L1抑制剂可显著抑制膀胱癌的进展,其效应可能是通过调节肿瘤微环境,抑制肿瘤细胞的上皮间质转化来实现的。