Evolving immunosuppressive microenvironment during human cervical carcinogenesis

Chronic infection with human papillomavirus (HPV) can result in cervical cancer. To understand how HPV escapes immune eradication, we examined biophenotypes of immune cells in human normal cervix, cervical intraepithelial neoplasia (CIN), and cancer. Expression and cellular localization of Forkhead box protein-3 (FOXP3), indolamine 2,3-dioxygenase (IDO), interleukin (IL)-10, and interferon (IFN)-γ were examined by immunofluorescence and immunohistochemistry. Mean cell densities of stromal FOXP3+ cells, IDO+ cells, IL-10+ cells, CD1a+ cells, and macrophages significantly increased from normal cervix to cancer, whereas densities of IFN-γ+ and MMP-9+ cells increased from normal cervix to CIN but decreased in cancer. Flow cytometry confirmed significant elevation of cervical T cells expressing IFN-γ and transforming growth factor-β in CIN compared with normal cervix. Upon activation, a significantly increased proportion of cervical T cells expressed IFN-γ in CIN than normal. A unique subset of morphologically immature stromal dendritic cells expressing IL-10 and IDO was more numerous in cancer than in normal cervix and CIN. The potentially suppressive immune milieu in the cervix may be permissive of HPV-associated cervical carcinogenesis.     

MDSC在自身免疫疾病中的作用

髓系抑制细胞（Myeloid derived suppressor cells,MDSC）是具有抑制功能的髓系来源的细胞群。在自身免疫疾病中,MDSC显著增多,并在体外有抑制功能,然而在体内研究中,MDSC的研究存在争议。最新研究发现具有抑制功能的MDSC的显著增多并不能有效缓解自身免疫疾病,而且在某些情况下甚至促进疾病的进展。因此,MDSC在自身免疫疾病的作用有待进一步研究。本文根据已有文献,综述了MDSC在不同的自身免疫疾病中的改变及机制。     

Enhancing T cell therapy by overcoming the immunosuppressive tumor microenvironment

Immune response to tumors can be successfully oriented for therapeutic purposes, as shown by the clinical efficacy of checkpoint blockade in extending the survival of patients with certain solid and hematologic neoplasms. Nonetheless, numerous patients do not benefit from these new treatments. Tumor-specific CD8⁺ T lymphocytes, either endogenously revived by checkpoint interference or adoptively transferred after in vitro expansion and retargeting, can be extremely efficient in controlling metastatic disease but have to overcome a number of restraints imposed by growing tumors. This immune escape relies on a profound modification of the tumor environment, which is rendered less permissive to lymphocyte arrival, persistence, and functional activity. We review here emerging findings on the main negative circuits limiting the efficacy of cancer immunotherapy, as well as novel and conventional approaches that can translate into rational combination therapies.     

微环境对体外间充质干细胞向心肌样细胞分化的作用

目的研究心肌组织中何种细胞对骨髓间充质干细胞(MSCs)向心肌样细胞定向分化起决定性作用。方法分离培养骨髓MSCs、心肌细胞(CM)和内皮细胞(EC)。MSCs经BrdU标记后与CM、EC分别共培养和单独培养,通过形态学、免疫细胞化学和双重免疫细胞化学鉴定。结果分离培养的MSCs、CM和EC纯度高于95%。标记MSCs与CM共培养后,细胞具有心肌细胞样形态。4周时,有44%的细胞BrdU与肌动蛋白(sarcomeric actin)或连接蛋白-43(connexin-43)双重免疫细胞化学染色阳性。与EC共培养以及单独培养时,MSCs形态变化不明显,无双染阳性细胞出现。结论CM对骨髓MSCs向心肌样细胞的定向分化具有重要作用。     

Role of the thymus in regulation of stromal cells transferring the hematopoiesis-inducing microenvironment in stress

Research Institute of Pharmacology, Tomsk Scientific Center, Academy of Medical Sciences of the USSR. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 12, pp. 710–712, December, 1989.     

Effects of doxorubicin on the canine erythroid and myeloid progenitor cells and bone marrow microenvironment

The antineoplastic drug doxorubicin is known to cause cytopenias. In humans and in dogs treated with doxorubicin, neutropenia is a common haematological toxicity. To determine the mechanism of doxorubicin haematotoxicity in the dog, in vitro bone marrow progenitor and microenvironment assays were done in the presence of doxorubicin. The 50% inhibitory concentration (IC50) of doxorubicin for canine erythroid colony-forming unit (CFU-E) was 0.042 ± 0.01 M and for canine granulocyte-macrophage colony-forming unit (CFU-GM) it was 0.0084 ± 0.002 M To determine the effects of doxorubicin on the bone marrow microenvironment, fibroblast colony-forming unit (CFU-F) assays were performed. The 50% inhibitory concentration for canine CFU-F was 0.030 ± 0.01 M. Morphologically, the CFU-F were made up of predominantly cells (73 ± 8%) with fibroblast-like morphology. Within the colonies as well as between the colonies, there were cells with macrophage (27 ± 8%) morphology. To support the morphological classification of these cells, cytochemical staining was done. The cells with the fibroblast-like morphology were negative for butyrate esterase and those with macrophage morphology were positive, whereas both cell types were positive for acid phosphatase in the presence or absence of tartrate. Our data show that the effects of doxorubicin on in vitro haematopoiesis in the dog are similar to those described in man.     

Role of the microenvironment in immune responses to transplantation

Through the constant interplay of cellular and extracellular components, the microenvironment of tissues directs immune responses. In solid organ transplantation, one factor that significantly alters the microenvironment of tissues is reperfusion injury, which occurs to a certain extent in essentially all cadaver organs. The damage that results from reperfusion injury initiates a cascade of signals to surveillance cells such as macrophages, mast cells, and dendritic cells, augmenting both innate and allo-immune responses. Chemokines, released from surveillance cells and others, orchestrate an influx of cells into the allograft, and subsequently drive the migration of dendritic cells and lymphocytes to proper areas within lymph nodes for the efficient generation of allo-immune responses. Heparan sulfate, a component of the extracellular matrix, binds chemokines and thus regulates their localization within tissues. This association is one of a multitude of examples of the interplay between cells and their extracellular surroundings. In addition to the association with chemokines, heparan sulfate binds cytokines such as IFN- and IL-2. In the spleen, heparan sulfate localizes IL-2 to the marginal zone, red pulp, and interdigitating dendritic cells of the T cell zone. Our laboratory recently determined that the contribution of heparan sulfate-bound IL-2 to immune responses is substantial, finding that bound, rather than free, IL-2 drives immune responses. This finding reiterates the critical nature of the interaction between cells and the extracellular matrix. Disruptions in these interactions may lead to dysregulation of immune responses and, in turn, pathologies such as tissue fibrosis or autoimmunity. Further studies into the exchange between cells and the extracellular matrix will likely lead to new lines of therapies aimed at correcting these abnormalities before irreversible damage occurs.     

Neonatal myeloid derived suppressor cells show reduced apoptosis and immunosuppressive activity upon infection with Escherichia coli

Susceptibility to infection during the neonatal period and reduced control of inflammation in neonates are attributed to immunosuppression persisting from fetal life. Myeloid‐derived suppressor cells (MDSCs) are immature myeloid progenitors with suppressive activity and increased numbers in cord blood. We hypothesized that MDSCs contribute to innate host defence in neonates, paralleled by anti‐inflammatory signalling.Phagocytic activity, infection induced apoptosis, expression of B‐cell lymphoma (Bcl)‐2 family proteins, production of reactive oxygen species (ROS), cytokine production and T‐cell suppression of neonatal granulocytic‐MDSCs (G‐MDSCs) after infection with Escherichia coli (E. coli) were compared to neonatal autologous mature polymorphonuclear leukocytes (PMNs). Phagocytic activity of G‐MDSCs upon infection with E. coli was equal to that of mature PMNs, however, apoptosis of G‐MDSCs was decreased. G‐MDSCs showed enhanced Bcl‐2‐expression and lower ROS production compared to PMNs. Inhibition of Bcl‐2 reduced apoptosis rates of G‐MDSCs to that of mature PMNs. Induction of anti‐inflammatory transforming growth factor beta (TGF‐β) was enhanced, while pro‐inflammatory IL‐8 decreased in G‐MDSCs compared to PMNs. Infected G‐MDSCs strongly suppressed proliferation of T cells. We show a direct role of G‐MDSCs for anti‐bacterial host defence. Prolonged survival and anti‐inflammatory capacity suggest that G‐MDSCs are important for immune‐regulation after bacterial infection.     

Role of CD34 antigen in myeloid differentiation of human hematopoietic progenitor cells

CD34 is a transmembrane protein that is strongly expressed on hematopoietic stem/progenitor cells (HSCs); despite its importance as a marker of HSCs, its function is still poorly understood, although a role in cell adhesion has been demonstrated. To characterize the function of CD34 antigen on human HSCs, we examined, by both inhibition and overexpression, the role of CD34 in the regulation of HSC lineage differentiation. Our results demonstrate that CD34 silencing enhances HSC granulocyte and megakaryocyte differentiation and reduces erythroid maturation. In agreement with these results, the gene expression profile of these cells reveals the upregulation of genes involved in granulocyte and megakaryocyte differentiation and the downregulation of erythroid genes. Consistently, retroviral-mediated CD34 overexpression leads to a remarkable increase in erythroid progenitors and a dramatic decrease in granulocyte progenitors, as evaluated by clonogenic assay. Together, these data indicate that the CD34 molecule promotes the differentiation of CD34+ hematopoietic progenitors toward the erythroid lineage, which is achieved, at least in part, at the expense of granulocyte and megakaryocyte lineages.     

Role of myeloid cells in the regulation of group 2 innate lymphoid cell-mediated allergic inflammation

Group 2 innate lymphoid cells (ILC2s) are an important component of the innate immune system that execute important effector functions at barrier surfaces, such as lung and skin. Like T helper type 2 cells, ILC2s are able to release high amounts of type 2 cytokines that are essential in inducing allergic inflammation and eliminating helminth infections. The past few years have contributed to our better understanding of the interactions between ILC2s and other cells of the immune system via soluble factors or in a cell–cell contact manner. Myeloid cells, including mononuclear leukocytes and polymorphonuclear leukocytes, are excellent sensors of tissue damage and infection and can influence ILC2 responses in the process of allergic inflammation. In this review, we summarize recent insights on how myeloid cell subsets regulate ILC2 activation with focus on soluble factors in the context of allergic inflammation.     

肿瘤微环境中的基质细胞在转移形成中的角色

传统观念认为癌症的进展仅仅是由癌细胞基因和表型变化的多个过程所致.但最近20年的研究显示肿瘤微环境(tumor microenvironment,TME)对于肿瘤行为的影响是同等重要的.TME的组成包括局部的基质细胞,如定植的成纤维细胞(cancer-associated fibroblasts,CAF)和巨噬细胞,远处招募的细胞如内皮细胞、免疫细胞包括髓系和淋巴系细胞、骨髓来源的前体细胞和循环中的血小板.TME能够分泌影响并调控肿瘤表型的分子,如能揭示成瘤细胞与微环境之间的关系,必定能够为肿瘤的发生发展及治疗等一系列难题提供全新的视角.     

Role of myeloid differentiation factor 88 in HSP60 signal transduction in dendritic cells

Objective: To explore the role and mechanism of myeloid differentiation factor88 (MyD88) in HSP60 signal transduction in dendritic cells. Methods:Mouse DCs were cultured from murine bone marrow cells. The DC marker CD11c was detected by flow cytometry, then DCs were divided into control group, HSP60 groupand RNA interference group. Control group was cultured under normal condition, and HSP60 group was cultured with 10 μg/ml of HSP60. RNA interference group was first cultured with MyD88 siRNA forl2 hours and then HSP60 was added into the culture mixture. All groups were cultured for 48 hours. Immunochemistry was used to detect the concentration of MyD88 and NF- κB. Western blot was used to detect the concentration of MyD88. Flow cytometry and mixed lymphocyte reaction (MLR) were used to detect the phenotype and functional properties of DCs. ELISA was used to detect the concentration of TNF-α, IFN-γ and IL-12 in the supernatant. Results:The expression of CD11c in marine bone marrow DCs was 88.76%. HSP60 stimulation increased the expression of CD80, CD86, MHC-Ⅱ in DCs and TNF-α, IFN-γ, IL-12 secretion in the supematant. HSP60 stimulation also increased the level of MyD88 in the cytoplasm and promoted the shift of NF-κB to karyon and the proliferation of allogeneic T cells. MyD88 siRNA could decreaseMyD88 and inhibit these effects induced by HSP60. Conclusion:HSP60 activates DCs through MyD88-dependent pathway. MyD88 plays a critical role in HSP60 signal transduction. Inhibition of MyD88 may be a novel way for treating disease correlated with HSP60.     

成体神经干细胞与微环境

背景：成体神经干细胞广泛分布于中枢神经系统,它存在于特殊的微环境中,有自我更新和分化能力,可作为内源性干细胞来源来修复受损的神经组织。 目的：归纳总结神经干细胞与微环境的研究与进展。 方法：由第一作者检索PubMed(1989至2012年)数据库与中国期刊全文数据库(CNKI：2001至2012年),检索词分别为“神经干细胞;微环境;调控”和“neural stem cells;microenviroment;regulation”。 结果与结论：阅读文题和摘要进行筛选,选择具有原创性,论点论据可靠且分析全面、密切相关的文章,排除重复性研究与以及质量较差文章,共检索到379篇英文文章,131篇中文文章,按纳入及排除标准筛选后,共纳入64篇文章。微环境中的各种组成成分如血管及内皮细胞、星形胶质细胞、室管膜细胞、细胞外基质与神经干细胞关系密切,在成体神经干细胞的生存、增殖、分化调控中均发挥重要作用。同时,成体神经干细胞的分化受基因调控。成体神经干细胞与微环境两者之间的研究将为神经组织的修复带来新的方向。     

Nocardia brasiliensis induces an immunosuppressive microenvironment that favors chronic infection in BALB/c mice

Nocardia brasiliensis is an intracellular microorganism and the most common etiologic agent of actinomycetoma in the Americas. Several intracellular pathogens induce an immunosuppressive microenvironment through increases in CD4+ Foxp3+ regulatory T cells (Treg), thus downregulating other T-cell subpopulations and assuring survival in the host. In this study, we determined whether N. brasiliensis modulates T-lymphocyte responses and their related cytokine profiles in a murine experimental model. We also examined the relationship between N. brasiliensis immunomodulation and pathogenesis and bacterial survival. In early infection, Th17/Tc17 cells were increased at day 3 (P < 0.05) in footpad tissue and spleen. Treg subpopulations peaked at days 7 and 15 (P < 0.01) in the footpad and spleen, respectively. Transforming growth factor β1 (TGF-β1) and interleuki-10 (IL-10) are cytokines known for their immunosuppressive effects. During early and chronic infections, these cytokines were elevated with increased TGF-β1 levels from days 3 to 30 (P < 0.01) and sustained IL-10 expression throughout infection compared to uninfected mice. IL-6 production was increased at day 3 (P < 0.01), whereas gamma interferon (IFN-γ), IL-17A, and IL-23 levels were highest at day 15 postinfection (P < 0.01) when a decrease in the bacterial load (>1 log) was also observed (P < 0.05). After these changes, at 30 to 60 days postinfection, IFN-γ production was decreased, whereas the expression of anti-inflammatory cytokines and the bacterial load again increased (P < 0.05). The increment in Treg cells and the related cytokine profile correlated with reduced inflammation at day 15 (P < 0.05) in the footpad. We conclude that N. brasiliensis modulates the immune system to induce an immunosuppressive microenvironment that benefits its survival during the chronic stage of infection.