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1.
JC virus (JCV), a common human polyomavirus, is the etiological agent of the demyelinating disease, progressive multifocal leukoencephalopathy (PML). In addition to its role in PML, studies have demonstrated the transforming ability of the JCV early protein, T-antigen, and its association with some human cancers. JCV infection occurs in childhood and latent virus is thought to be maintained within the bone marrow, which harbors cells of hematopoietic and non-hematopoietic lineages. Here we show that non-hematopoietic mesenchymal stem cells (MSCs) isolated from the bone marrow of JCV T-antigen transgenic mice give rise to JCV T-antigen positive cells when cultured under neural conditions. JCV T-antigen positive cells exhibited neural crest characteristics and demonstrated p75, SOX-10 and nestin positivity. When cultured in conditions typical for mesenchymal cells, a population of T-antigen negative cells, which did not express neural crest markers arose from the MSCs. JCV T-antigen positive cells could be cultured long-term while maintaining their neural crest characteristics. When these cells were induced to differentiate into neural crest derivatives, JCV T-antigen was downregulated in cells differentiating into bone and maintained in glial cells expressing GFAP and S100. We conclude that JCV T-antigen can be stably expressed within a fraction of bone marrow cells differentiating along the neural crest/glial lineage when cultured in vitro. These findings identify a cell population within the bone marrow permissible for JCV early gene expression suggesting the possibility that these cells could support persistent viral infection and thus provide clues toward understanding the role of the bone marrow in JCV latency and reactivation. Further, our data provides an excellent experimental model system for studying the cell-type specificity of JCV T-antigen expression, the role of bone marrow-derived stem cells in the pathogenesis of JCV-related diseases and the opportunities for the use of this model in development of therapeutic strategies.  相似文献   

2.
Suppressor of cytokine signaling (SOCS)-3 has been suggested to regulate CXCR4 signaling in a variety of human cell lines. In mice, conditional SOCS3 inactivation in hematopoietic cells including B-lineage lymphocytes has been reported to exacerbate CXCR4-signaling and focal adhesion kinase phosphorylation, which resulted in altered immature B cell distribution in bone marrow (BM) due to sustained α4β1 integrin-mediated adhesion to the extracellular matrix. However, a recent study examining conditional SOCS3 deletion specifically in B-lineage cells failed to detect significant roles in B-lineage cell retention in BM. In this study we carefully examined the role played by SOCS3 in CXCR4 signaling in developing B cell subsets. We show that in mice conditionally deficient in SOCS3 exclusively in B cells (Socs3 fl/fl Mb1 cre/+) there was no detectable difference in B cell development in BM and in periphery. We show that SOCS3 deficient and sufficient immature B cell subsets are similarly distributed between BM parenchyma and sinusoids, and are equally competent at exiting BM into peripheral blood. Furthermore, we found no significant differences in CXCR4 desensitization upon ligand exposure in developing B lymphocyte subsets. Consequently, SOCS3-deficient and sufficient B-lineage cell migration towards CXCL12 in vitro was undistinguishable, and B-lineage cell amoeboid motility within BM parenchyma was also unaffected by SOCS3-deficiency. Thus we conclude that SOCS3 has no detectable influence on biological processes known to be controlled by CXCR4 signaling.  相似文献   

3.
Macrophages play a key role in the innate immune system. Macrophages are thought to originate from hematopoietic precursors or the yolk sac. Here, we describe the in vitro establishment of self-renewable GM-CSF-dependent immature macrophages (GM-IMs) from murine bone marrow (BM). GM-IMs grow continuously in vitro in conditioned medium containing GM-CSF. The immunophenotype of GM-IMs is F4/80high CD11bhigh CD11clow Ly6Clow. By comparing gene expression in GM-IMs and BM dendritic cells, we found that GM-IMs expressed lower levels of chemokines, cytokines and their receptors. GM-IMs are round in shape, attach loosely to non-coated culture dishes and have a marked phagocytic capacity. These results indicate that GM-IMs are macrophage precursor cells. Following stimulation with LPS, monocyte-like GM-IMs converted to flat macrophage-like cells that tightly adhered to non-coated culture dishes and produced pro-inflammatory cytokines TNFα, IL-6 and IL-1β. These results indicated that GM-IMs differentiated to M1 pro-inflammatory macrophages. This was confirmed by stimulation of GM-IMs with IFNγ, an inducer of M1 markers. GM-IMs showed enhanced expression of M2 macrophage markers such as Arg1 and Retnla following stimulation by Th2 cytokines IL-4 and IL-13. When GM-IMs were injected into mice at sites of wounding, wound repair was enhanced. These results indicate that GM-IMs can differentiate to M2 macrophages. When GM-IMs were injected into clodronate-treated mice, they induced resident macrophage proliferation by producing M-CSF. In conclusion we have established self-renewable GM-CSF-dependent immature macrophages in vitro from murine BM, which differentiate to M1 or M2 macrophages.  相似文献   

4.
Eighteen isolates of anaerobic coryneforms from human bone marrow and skin and four type strains of Propionibacterium were studied chemically, biochemically and antigenically. All of the isolates were identified as Propionibacterium acnes; of the 18 isolates, 16 belonged to serotype I and two to serotype II. By means of gas liquid chromatography and mass spectral analysis, a large amount of iso-type fatty acids, such as iso-pentadecanoic and iso-heptadecanoic acids were detected in whole cells of isolates and type strains. Antitumor and adjuvant effects of the isolates and type strains were found to differ considerably among the strains. One of the isolates, P. acnes C-7, which showed potent biological activities was fractionated by hot phenol-water extraction. The resulting insoluble middle layer was found the most effective in tumor protection, adjuvant action in immune response and phagocytic activity in mice.  相似文献   

5.
骨髓间充质干细胞免疫抑制作用及其机理   总被引:2,自引:0,他引:2  
近年来间充质干细胞特殊的免疫学特性越来越引起人们的重视,使其成为移植领域的一个研究热点。许多实验室就间充质干细胞的免疫抑制作用和机理做了大量的研究工作,取得了一定的进展。本文简要综述间充质干细胞的免疫抑制作用和机理。  相似文献   

6.
7.
We have studied the in vivo tropism of human herpesvirus 6 (HHV-6) for hemopoietic cells in patients with latent HHV-6 infection. Having used a variety of cell purification, molecular, cytogenetic, and immunocytochemical procedures, we report the first evidence that HHV-6 latently infects early bone marrow progenitor cells and that HHV-6 may be transmitted longitudinally to cells which differentiate along the committed pathways.  相似文献   

8.
Using a 27 gauge hypodermic needle, bone marrow is aspirated from a lumbar vertebra into 0.1 ml of Hanks' salt solution. The aspirate is kept well mixed in 1% sodium citrate for 15 min, centrifuged, and the cell pellet fixed for 30 min in Clarke's 3:1 ethanol-acetic fixative. After removal of the fixative the cells are suspended in 0.05-0.1 ml of 60% acetic acid, centrifuged and resuspended in 0.03 ml of this fixative. Chromosome preparations are made by spreading the suspension on a slide heated to 60 C.  相似文献   

9.
目的:探讨参麦注射液对于白血病骨髓抑制期的治疗作用。方法:选取我院2011 年1 月至2012 年12 月收治的白血病的患者47 例,随机分为两组,观察组24 例化疗的同时给予参麦注射液,观察组患者23 例只给予化疗,比较两组患者化疗后的骨髓抑制情况和感染发生情况。结果:两组患者化疗效果显示总有效率分别为66.7%和65.2%,无显著差别(P〉0.05)。两组患者化疗骨髓抑制后WBC, Hb, PLT 的恢复时间分别为(6.32± 2.75)天,(9.32± 2.12)天和(7.31± 3.21)天,明显低于对照组(11.34± 4.34)天,(12.54± 3.21)天和(12.41± 4.32)天,差异显著有统计学意义(P〈0.05);观察组患者中性粒细胞ANC〈0.5× 10^9/L持续的时间明显少于对照组,差异明显有统计学意义(P〈0.05);观察组患者发生感染的比例明显低于对照组,差异显著有统计学意义(P〈0.05)。结论:参麦注射液可以明显减轻白血病化疗后的骨髓抑制现象,有效保护骨髓的造血功能,缩短骨髓受抑制时间,和降低感染率,明显提高患者生活质量。  相似文献   

10.
 已经证明一些细胞象脾淋巴细胞、血T细胞、自然杀伤细胞和血小板存在有阿片受体。本文在骨髓细胞上的研究提示未成熟B细胞表面也存在有这类神经肽的受体,通过阿片肤类结合到细胞上可以观察到不同的效应。试验结果显示M-脑啡肽、L-脑啡肽和α-内啡肽对骨髓未成熟B细胞抗体生成反应的抑制分别为76.6%、68.6%和67.7%。相反,β-内啡肽增进抗体反应达78.0%。M-脑啡肽和两种内啡肽在未成熟B细胞上的效应能够被拮抗剂纳络酮所逆转,提示反应涉及阿片肽受体机制。  相似文献   

11.
目的:获得高纯度的小鼠支持细胞,用以研究睾丸支持细胞在诱导胚胎干细胞向雄性生殖细胞分化过程中的作用,同时借助睾丸支持细胞减少进行体内诱导试验时可能产生的免疫排斥反应。方法:用胶原酶和胰蛋白酶组合消化结合选择性贴壁法从1周龄昆明白小鼠睾丸分离获得睾丸支持细胞,纯化后进行体外培养,观察其体外培养的生物学特性。结果:睾丸支持细胞体外培养3~4h即贴壁,贴壁后伸出3~4个突起,为成纤维型细胞,在体外培养2~3d即长满全瓶。油红Ο染色显示,其胞质含有大量脂滴。透射电镜观察结果表明,支持细胞核仁周围有卫星核小体。RT-PCR结果显示获得的细胞表达缪勒管抑制物,不表达促黄体素受体和小鼠VASA同源物。结论:获得了较高纯度的小鼠睾丸支持细胞,可以用于诱导小鼠胚胎干细胞向雄性生殖细胞分化的体内和体外试验。  相似文献   

12.
13.
目的:探讨参麦注射液对于白血病骨髓抑制期的治疗作用。方法:选取我院2011年1月至2012年12月收治的白血病的患者47例,随机分为两组,观察组24例化疗的同时给予参麦注射液,观察组患者23例只给予化疗,比较两组患者化疗后的骨髓抑制情况和感染发生情况。结果:两组患者化疗效果显示总有效率分别为66.7%和65.2%,无显著差别(P0.05)。两组患者化疗骨髓抑制后WBC,Hb,PLT的恢复时间分别为(6.32±2.75)天,(9.32±2.12)天和(7.31±3.21)天,明显低于对照组(11.34±4.34)天,(12.54±3.21)天和(12.41±4.32)天,差异显著有统计学意义(P0.05);观察组患者中性粒细胞ANC0.5×109/L持续的时间明显少于对照组,差异明显有统计学意义(P0.05);观察组患者发生感染的比例明显低于对照组,差异显著有统计学意义(P0.05)。结论:参麦注射液可以明显减轻白血病化疗后的骨髓抑制现象,有效保护骨髓的造血功能,缩短骨髓受抑制时间,和降低感染率,明显提高患者生活质量。  相似文献   

14.
目的研究小鼠腹腔注射紫杉醇对体外骨髓细胞诱导分化巨噬细胞的影响。方法小鼠连续5d腹腔注射紫杉醇,无菌制备骨髓细胞,用含巨噬细胞集落刺激因子(M-CSF)的RPMI1640培养液培养骨髓细胞,通过流式细胞仪对其诱导分化的巨噬细胞表面分子、吞噬功能进行分析。结果紫杉醇明显降低小鼠骨髓细胞数量,但骨髓细胞体外诱导分化成巨噬细胞的数量明显增加;F4/80^+巨噬细胞中CD80、CD14表面分子表达升高,而I-A^d表达降低;紫杉醇处理组诱导分化的巨噬细胞吞噬鸡红细胞的能力提高。结论结果提示紫杉醇可能具有调节巨噬细胞表面分子的表达和吞噬功能。  相似文献   

15.
Tumor xenografts in immunodeficient mice, while routinely used in cancer research, preclude studying interactions of immune and cancer cells or, if humanized by allogeneic immune cells, are of limited use for tumor-immunological questions. Here, we explore a novel way to generate cancer models with an autologous humanized immune system. We demonstrate that hematopoietic stem and progenitor cells (HSPCs) from bone marrow aspirates of non-metastasized carcinoma patients, which are taken at specialized centers for diagnostic purposes, can be used to generate a human immune system in NOD-scid IL2rγ(null) (NSG) and HLA-I expressing NSG mice (NSG-HLA-A2/HHD) comprising both, lymphoid and myeloid cell lineages. Using NSG-HLA-A2/HHD mice, we show that responsive and self-tolerant human T cells develop and human antigen presenting cells can activate human T cells. As critical factors we identified the low potential of bone marrow HSPCs to engraft, generally low HSPC numbers in patient-derived bone marrow samples, cryopreservation and routes of cell administration. We provide here an optimized protocol that uses a minimum number of HSPCs, preselects high-quality bone marrow samples defined by the number of initially isolated leukocytes and intra-femoral or intra-venous injection. In conclusion, the use of diagnostic bone marrow aspirates from non-metastasized carcinoma patients for the immunological humanization of immunodeficient mice is feasible and opens the chance for individualized analyses of anti-tumoral T cell responses.  相似文献   

16.
17.
Intermittent administration of parathyroid hormone (PTH) dramatically increases bone mass and currently is one of the most effective treatments for osteoporosis. However, the detailed mechanisms are still largely unknown. Here we demonstrate that conditioned media from PTH-treated osteoblastic and osteocytic cells contain soluble chemotactic factors for bone marrow mesenchymal progenitors, which express a low amount of PTH receptor (PTH1R) and do not respond to PTH stimulation by increasing cAMP production or migrating toward PTH alone. Conditioned media from PTH-treated osteoblasts elevated phosphorylated Akt and p38MAPK amounts in mesenchymal progenitors and inhibition of these pathways blocked the migration of these progenitors toward conditioned media. Our previous and current studies revealed that PTH stimulates the expression of amphiregulin, an epidermal growth factor (EGF)-like ligand that signals through the EGF receptor (EGFR), in both osteoblasts and osteocytes. Interestingly, conditioned media from PTH-treated osteoblasts increased EGFR phosphorylation in mesenchymal progenitors. Using several different approaches, including inhibitor, neutralizing antibody, and siRNA, we demonstrate that PTH increases the release of amphiregulin from osteoblastic cells, which acts on the EGFRs expressed on mesenchymal progenitors to stimulate the Akt and p38MAPK pathways and subsequently promote their migration in vitro. Furthermore, inactivation of EGFR signaling specifically in osteoprogenitors/osteoblasts attenuated the anabolic actions of PTH on bone formation. Taken together, these results suggest a novel mechanism for the therapeutic effect of PTH on osteoporosis and an important role of EGFR signaling in mediating PTH''s anabolic actions on bone.  相似文献   

18.

Background

Although multimodality treatment can induce high rate of remission in many subtypes of non-Hodgkin''s lymphoma (NHL), significant proportions of patients relapse with incurable disease. The effect of human bone marrow (BM) mesenchymal stem cells (MSC) on tumor cell growth is controversial, and no specific information is available on the effect of BM-MSC on NHL.

Methodology/Principal Findings

The effect of BM-MSC was analyzed in two in vivo models of disseminated non-Hodgkin''s lymphomas with an indolent (EBV Burkitt-type BJAB, median survival = 46 days) and an aggressive (EBV+ B lymphoblastoid SKW6.4, median survival = 27 days) behavior in nude-SCID mice. Intra-peritoneal (i.p.) injection of MSC (4 days after i.p. injection of lymphoma cells) significantly increased the overall survival at an optimal MSC∶lymphoma ratio of 1∶10 in both xenograft models (BJAB+MSC, median survival = 58.5 days; SKW6.4+MSC, median survival = 40 days). Upon MSC injection, i.p. tumor masses developed more slowly and, at the histopathological observation, exhibited a massive stromal infiltration coupled to extensive intra-tumor necrosis. In in vitro experiments, we found that: i) MSC/lymphoma co-cultures modestly affected lymphoma cell survival and were characterized by increased release of pro-angiogenic cytokines with respect to the MSC, or lymphoma, cultures; ii) MSC induce the migration of endothelial cells in transwell assays, but promoted endothelial cell apoptosis in direct MSC/endothelial cell co-cultures.

Conclusions/Significance

Our data demonstrate that BM-MSC exhibit anti-lymphoma activity in two distinct xenograft SCID mouse models of disseminated NHL.  相似文献   

19.
《Cell Stem Cell》2014,14(4):460-472
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20.
From 44 to 100% of sera from patients with infectious mononucleosis exhibited the capacity to stimulate colony formation in vitro by mouse bone marrow cells. The proportion of sera with colony-stimulating activity was highest in patients with a short fever period and developing low Paul-Bunnell titres. Patients with a more severe course of the disease generally displayed no, or only weak, colony-stimulating activity in their sera, and also had higher Paul-Bunnell titres. The level of serum colony-stimulating activity tended to fall in the convalescent stages of the disease.  相似文献   

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