Cathelicidin Gene Expression in Porcine Tissues: Roles in Ontogeny and Tissue Specificity

Cathelicidins constitute a family of mammalian antimicrobial peptides that are synthesized in the bone marrow as prepropeptides, stored in neutrophil granules as propeptides, and released as active, mature peptides upon neutrophil degranulation. We investigated the developmental expression of two porcine cathelicidins, PR-39 and protegrin. Both cathelicidins were expressed constitutively in the bone marrow of all pigs at all of the ages tested. Peripheral blood neutrophils from young pigs expressed PR-39 and protegrin mRNA, which were not detectable at 42 days of age. At earlier ages, expression of PR-39 mRNA was detected in the kidney and liver and several lymphoid organs, including the thymus, spleen, and mesenteric lymph nodes, but disappeared at 4 weeks of age. These data provide the first evidence of cathelicidin gene expression in peripheral leukocytes and may indicate a role for these antimicrobial peptides in the development of host defense mechanisms.     

Bacterial DNA indicated as an important inducer of fish cathelicidins

Cathelicidins are antimicrobial peptides indicated as important in the control of the natural microflora as well as in the fight against bacterial invasion in mammals. Little is known about cathelicidins in fish and here the Chinook salmon (Oncorhynchus tshawytscha) embryo cell line (CHSE-214) was used as a model system to study the expression of cathelicidins due to fish pathogenic bacteria. The cDNA of cathelicidin from CHSE-214 cells (csCath) was cloned and shown to be closely related to gene 2 of both rainbow trout and Atlantic salmon. The deducted amino acid sequence showed highest sequence identity to rtCath2 with 95% and 72% for the cathelin and the antibacterial part, respectively. Cathelicidin gene expression was studied and various Gram positive and Gram negative bacteria caused the upregulation of the gene (csCath). Bacterial DNA and protein were shown important for the induction of cathelicidin expression in these cells. LPS (Escherichia coli) also causes the upregulation of cathelicidins, but digestion of the LPS with DNase I before incubation of the cells, totally abolished the upregulation of cathelicidin and suggests DNA contamination in the LPS to be the trigger for this effect. These results could explain the limited responsiveness of fish cells towards pure LPS and confirm previous suggestions that fish cells are less sensitive to LPS than mammalian cells.     

Participation of mammalian defensins and cathelicidins in anti-microbial immunity: receptors and activities of human defensins and cathelicidin (LL-37)

Defensins and cathelicidins are the two major families of mammalian anti-microbial proteins. They contribute to host, innate, anti-microbial defense by disrupting the integrity of the bacterial cell membrane. However, several members of the mammalian anti-microbial proteins including defensins and cathelicidins have been shown recently to have chemotactic effects on host cells. Human neutrophil alpha-defensins are chemotactic for resting, na?ve CD45RA/CD4 T cells, CD8 T cells, and immature dendritic cells. Human beta-defensins are also chemotactic for immature dendritic cells but induce the migration of memory CD45RO/CD4 T cells. In contrast, cathelicidin/LL-37 is chemotactic for neutrophils, monocytes, and T cells but not for dendritic cells. Thus, these anti-microbial peptides have distinct, host-target cell spectra. The chemotactic activities of human beta-defensins and cathelicidin/LL-37 are mediated by human CC chemokine receptor 6 and formyl peptide receptor-like 1, respectively. The capacities of defensins and cathelicidins to mobilize various types of phagocytic leukocytes, immature dendritic cells, and lymphocytes, together with their other effects such as stimulating IL-8 production and mast cell degranulation, provide evidence for their participation in alerting, mobilizing, and amplifying innate and adaptive anti-microbial immunity of the host.     

Acceleration of Immune Reconstitution after Bone Marrow Transplantation in Mice by Bone Marrow Stromal

To observe potential effect of the engineered bone marrow stromal cell line QXMSC1 secreting IL-6 (QXMSCIL-6) on accelerating immnune reconstitution in syngeneic bone marrow transplantation in mice, QXMSC1 was transfected with the eukaryocytic expression vector pcDNAIL-6, which contained hIL-6 cDNA by liposome-mediated gene transfecting technique. G418-resistance clone was selected by limiting dilution. The highest secreting clone was selected by ELISA assay and used in animal experiments. The recipient mice (BALB/c) were lethally irradiated and cotransplanted syngeneic bone marrow (10^7/mice) and the QXMSCIIL-6 (5×10^5/mice). Lymphocyte proliferation induced by ConA and LPS, helper T lymphocyte precursor (HTLp), cytotoxic T lymphocyte precursor (CTLp), plaque-forming cell (PFC), delayed type hypersensitivity (DTH) were examined 30, 60 days in post transplantation respectively. The results showed that lymphocytes proliferation to ConA and LPS, HTLp, CTLp increased, DTH and PFC were improved by cografted stromal cells QXMSCIIL-6 on 30, 60 days after BMT. These results demonstrated that the bone marrow stromal cell line QXMSC1 IL-6 transfected with IL-6 (QXMSC11L-6) accelerated immnune reconstitution in syngeneic bone marrow transplantation.     

Expression of interleukin-8 by lipopolysaccharide-stimulated bone marrow-derived mononuclear cells.

Interleukin-8 (IL-8) is a potent neutrophil chemoattractant, produced by a variety of immune and nonimmune cells in response to exogenous and host-derived inflammatory stimuli. We demonstrate here that a suspension of normal bone marrow mononuclear cells, consisting principally of myeloid precursors, produces IL-8 in response to stimulation with lipopolysaccharide (LPS). IL-8-specific mRNA is rapidly induced, being detected first 30 min after stimulation. IL-8 is detected by enzyme-linked immunosorbent assay within 2 h of stimulation, with steady a increase in its level through 72 h. Further studies demonstrated that LPS could serve as a primary stimulus for the expression of IL-8, since LPS challenge in the presence of cycloheximide resulted in superinduction of bone marrow mononuclear cell-derived IL-8 mRNA. These investigations suggest that the stimulatory effect of LPS is independent of other cytokines such as IL-1 beta. When compared with LPS, IL-1 beta proved to be a weak signal for the expression of IL-8 by bone marrow mononuclear cells. In a dose-response study, the maximum stimulatory concentration of IL-1 beta (300 pg/ml) resulted in the production of 500 pg of IL-8 per 10(6) cells, whereas 1 microgram of LPS resulted in the production of 5.5 ng/10(6) cells. Although IL-1 beta was not a particularly potent stimulus for IL-8 production by bone marrow mononuclear cells, peripheral blood mononuclear cells were highly susceptible to IL-1 beta challenge. In addition, the potential dependence of LPS-induced marrow-derived IL-8 production on the intermediate synthesis of IL-1 beta was further investigated. Results of studies assessing kinetics, addition of cycloheximide, and blocking with IL-1 beta neutralizing antibody were all consistent with the ability of LPS to directly induce bone marrow-derived IL-8 independently of IL-1 beta. These investigations demonstrate that bone marrow may be a significant source of IL-8 and may play a significant role in acute infectious, inflammatory responses.     

Notch信号在脂多糖诱导的骨髓间充质干细胞中的作用

目的:探讨Notch信号对脂多糖(lipopolysaccharide,LPS)诱导的小鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)增殖及白细胞介素6(interleukin-6,IL-6)和趋化因子CXCL1分泌的影响。方法:全骨髓培养法制备BMSCs;采用q PCR与Western blot实验比较LPS对BMSCs中Notch信号通路配体、受体及靶基因表达的变化;MTT法和活细胞计数检测Notch信号对细胞增殖的影响;并以ELISA法检测Notch信号通路抑制剂DAPT对IL-6和CXCL1分泌的调节作用。结果:经10μg/L、100μg/L和1 mg/L的LPS刺激后,BMSCs增殖和IL-6分泌呈现上升趋势(P0.05或P0.01)。q PCR与Western blot结果显示Notch信号通路受体和配体在BMSCs中均有表达,但LPS对其mRNA与蛋白水平并无明显影响,然而LPS可显著诱导Notch信号靶基因Hes1与Hey1的蛋白表达。Notch信号通路抑制剂DAPT可以降低LPS诱导的BMSCs活力的上升(P0.01),同时对LPS诱导的BMSCs增殖有抑制作用。另外,LPS显著诱导BMSCs中IL-6与CXCL1的分泌,而抑制Notch信号通路可显著抑制LPS所诱导的IL-6与CXCL1的分泌(P0.05)。结论:抑制Notch信号可以抑制LPS诱导的BMSCs增殖,并抑制IL-6与CXCL1的分泌。     

A set of genes selectively expressed in murine dendritic cells: utility of related cis-acting sequences for lentiviral gene transfer

Professional antigen presenting cells such as dendritic cells (DC) and macrophages (Mphi) share similar characteristics; however, they differ in their ability to initiate an immune response. DCs are much more potent in priming and stimulating nai;ve T-cells. Thus, DCs are good targets for the expression of foreign genes to elicit and specifically modify immune responses. To identify DC markers cDNA subtraction was performed using murine MHC class II(high), B7(high) bone marrow derived DCs as tester and interferon-gamma/E. coli lipopolysaccaride (LPS) treated bone marrow derived macrophages as driver. Analysis of 114 resulting clones revealed a diverse pattern of DC selective (DC(DeltaMphi)) gene expression including known genes whose expression in DCs had not been previously demonstrated as well as multiple novel genes. For several identified DC(DeltaMphi) genes, proximal promoter elements were isolated and incorporated into self-inactivating lentiviral GFP reporter vectors. Promoter activity was measured in bone marrow derived macrophages or dendritic cells. Of the promoters analyzed those for B7-DC and CCL17 drove strong GFP expression in DCs but not in resting or activated macrophages. The CCL17 promoter offered the highest level of expression in DCs and was further activated by culture with LPS or interleukin-4 (IL-4). In contrast, the B7-DC promoter was induced by IL-4 but not by LPS. Endogenous CCL17 and B7-DC mRNAs were increased similarly in IL-4 cultured DCs but only CCL17 was induced by LPS. Additionally, IL-4 increased cell surface expression of B7-DC in both immature and mature DCs.     

let-7f对骨髓间充质干细胞增殖的影响

背景：microRNA let-7f和炎性因子白细胞介素6对骨髓间充质干细胞的具体作用及两者之间是否存在联系尚不可知。 目的：分析let-7f及白细胞介素6表达水平对骨髓间充质干细胞增殖的影响及两者的关系。 方法：①构建let-7f过表达及抑制慢病毒载体,分别转染SD大鼠骨髓间充质干细胞,实验分为4个组：转染上调组(转染LV-rno-let-7f-up)、转染下调组(转染LV-rno-let-7f-down)、阴性转染组(转染空病毒)、未转染组(不进行病毒转染)。 qRT-PCR检测各组细胞let-7f表达水平。MTT法、流式细胞术和ELISA等方法检测不同let-7f表达水平下细胞增殖情况及白细胞介素6表达水平,qRT-PCR及Western blot检测各组Cyclin D1 mRNA和蛋白表达水平。②预测let-7f潜在的靶基因,构建野生型/突变型白细胞介素6 3’UTR报告基因载体,分别与let-7f/let-7f inhibitor共转染293T细胞系,测定荧光素酶活性。 结果与结论：let-7f转染上调组较未转染组及阴性转染组细胞增殖能力及克隆能力明显增强,G1期细胞数明显减少,S期明显增多,凋亡减少(P < 0.05);转染下调组结果与其相反。let-7f转染上调组细胞培养液中的白细胞介素6表达水平低于未转染组及阴性转染组(P < 0.05);转染下调组细胞培养液中的白细胞介素6则明显升高(P < 0.05);Western blot、定量PCR显示let-7f转染上调组Cyclin D1蛋白及mRNA表达上调(P < 0.05);转染下调组表达均下调(P < 0.05);未转染组与阴性转染组所有结果无明显差异(P > 0.05)。野生型白细胞介素6 3’UTR报告基因载体与let-7f共转染细胞的荧光素酶活性显著减低(P < 0.05)。结果表明上调let-7f表达水平可显著促进骨髓间充质干细胞增殖活性及克隆形成能力,减少凋亡,而下调let-7f表达水平则出现抑制作用。白细胞介素6过表达可抑制骨髓间充质干细胞增殖,考虑白细胞介素6是let-7f的靶基因,let-7f可能通过抑制白细胞介素6表达而促进细胞增殖。 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程      

Mechanisms mediating the inhibitory effect of all-trans retinoic acid on primitive hematopoietic stem cells in human long-term bone marrow culture

All-trans retinoic acid (RA) has generally been found to stimulate late committed (colony-forming unit- granulocyte, macrophage [CFU-GM]) and inhibit early (CFU-Blast) normal human myeloid progenitor cells. The present study provides the first evidence that the pharmacological concentration of 1 microM RA, exerts an inhibitory effect on the proliferation of functional human primitive hemopoietic stem cells (cobblestone area-forming cell [CFAC]) in long-term bone marrow cultures. Treatment of four-week confluent bone marrow culture with 1 microM RA for five days significantly reduced week 4 CAFC from 88 +/- 10 in control cultures to only 52 +/- 12 per 10(5) cells, p < 0.01. Quantitative enzyme-linked immunosorbent assay measurement of interleukin 6 (IL-6) and IL-11 produced from the four-week bone marrow stroma culture revealed only a slight and moderate increase of IL-6 and IL-11 production after treatment with RA. On the other hand, treatment with RA profoundly increased the soluble receptor gp130 released from the four-week bone marrow stroma by 7.5-fold from only 145 +/- 2.1 pg per ml in control cultures to 1,069.9 +/- 3.8 pg per ml in RA-treated cultures. A similar marked increase in the soluble adhesion molecules ICAM-1, and to a lesser extent VCAM-1, released from the four-week bone marrow stroma was observed after RA treatment. IL-6 has been implicated in the inhibitory effect of RA in several human hemopoietic and nonhemopoietic cells. The common transducing signal chain gp130, for all receptors of the IL-6 cytokine family, is expressed in most primitive human hemopoietic CD34(+) cells and its signaling was shown to synergize with other hemopoietic cytokines to expand primitive human hemopoietic stem cells. Recently, soluble gp130 was shown to be a natural potent antagonist of the human IL-6 cytokine family by binding the ligand and thereby reducing its bioavailability. The profound and rapid 7.5-fold increase in the natural antagonist of human IL-6 cytokine family after RA treatment could abrogate the gp130 signaling required for proliferation and/or expansion of human primitive hemopoietic stem cells and lead to the observed inhibitory effect of RA on CAFC. Both adhesion molecules VCAM-1 and ICAM-1 mediate human hemopoietic stem cell adhesion to marrow stroma. The present significant increase in the soluble form of these adhesion molecules after RA treatment could exert a significant antagonist effect on their function and hence may impair CAFC adhesion to marrow stroma. In conclusion, the RA inhibitory effect on the proliferation of primitive human hemopoietic stem cells could be mediated through: A) an impaired hemopoietic stem cell adhesion due to the significant increase in soluble adhesion molecules released from the marrow stroma after RA treatment, and B) a significantly reduced gp130 signaling that is necessary for stem cell proliferation due to the natural antagonistic effect of the profoundly increased level of soluble gp130 released from the marrow stroma after treatment with RA.     

Osteoblasts and stromal cells isolated from femora in rheumatoid arthritis (RA) and osteoarthritis (OA) patients express IL-11, leukaemia inhibitory factor and oncostatin M

We investigated both in vitro and ex vivo the role of mature osteoblasts (OB) and bone marrow stromal cells (BMSC) in RA and OA by analysing the expression of the following IL-6-type cytokines: IL-11, leukaemia inhibitory factor (LIF), oncostatin M (OSM) and IL-6. OB and BMSC were isolated from femora of RA, OA and post-traumatic (PT) patients, cultured in vitro in the presence or absence of IL-1beta and tumour necrosis factor-alpha (TNF-alpha), and assessed for the production and mRNA expression of IL-6-type cytokines. Trabecular bone biopsies were obtained from the inner portions of femoral heads and used for cytokine in situ immunostaining. Cultured OB and BMSC from different patients constitutively secreted IL-11 and IL-6 but not OSM. LIF was secreted only by BMSC, at very low levels. Interestingly, IL-11 basal production was significantly higher in BMSC than in OB in all three groups tested. IL-1beta and TNF-alpha strongly stimulated IL-6-type cytokine release (except for OSM) by both OB and BMSC. OSM was expressed only at mRNA levels in all groups studied. Cytokine immunostaining on bone biopsies confirmed the data obtained on cultured cells: IL-11, IL-6 and LIF proteins were detected both in mesenchymal (BMSC and OB) and mononuclear cells; OSM was found only in mononuclear cells. These data demonstrate that IL-6-type cytokines are constitutively expressed in the bone compartment in RA, OA and PT patients and can be secreted by bone cells at different stages of differentiation (BMSC and OB). This suggests that these cytokines may be involved in the mechanisms of bone remodelling in OA and RA.     

SETD4对脂多糖诱导的AML12细胞IL-6转录的调控作用

目的　探讨SETD4（SET-domain containing protein 4）对脂多糖（LPS）诱导的AML12（小鼠肝脏细胞系）细胞IL-6的转录调控作用。 方法　构建SETD4表达质粒和IL-6 启动子荧光素酶报告基因质粒,共转染小鼠肝脏细胞系AML12,使用双荧光素酶报告基因技术检测LPS刺激后IL-6 启动子荧光素酶活性;单独转染SETD4表达质粒上调AML12细胞SETD4表达,检测LPS刺激后IL-6 mRNA水平变化。 结果　双酶切鉴定及核酸测序证实重组质粒pcDNA3.0/HA-SETD4、pGL3.0/IL-6 promoter的构建成功。pcDNA3.0/HA-SETD4与pGL3.0/IL-6 promoter共转染AML12细胞,LPS刺激后SETD4对IL-6 启动子荧光素酶活性没有影响;上调SETD4表达后,可以促进LPS诱导的IL-6 mRNA转录。 结论　成功构建SETD4真核表达质粒和IL-6启动子荧光素酶报告基因质粒;SETD4对LPS诱导的AML12细胞IL-6的转录发挥正调控作用。     

IL-38 抑制LPS / TLR4 诱导炎症减轻类风湿关节炎的机制研究

目的:探讨IL-38 和TLR4 在类风湿关节炎中的潜在关联及其在类风湿性关节炎中致病的机制。方法:选取2013 年1 月至2016 年2 月间本院收治的41 例类风湿关节炎患者(观察组)及45 例本院实施创伤后滑膜切除术的患者(对照组)为研究对象。收集观察组和对照组的外周血单个核细胞(PBMCs)、滑膜组织及血清。荧光定量PCR 检测PBMCs 及滑膜组织中IL-38 及TLR4 的mRNA 水平。ELISA 检测滑膜液及血清中IL-38 的表达,Western blot 检测滑膜组织中IL-38 及TLR4的表达。LPS 和/ 或IL-38 刺激RAW264.7 细胞,ELISA 检测RAW264.7 细胞上清中IL-6、IL-8 及TNF-α的含量,荧光定量PCR检测RAW264.7 细胞TLR4、IL-6、IL-8 及TNF-α的表达。NF-κB 激活-核转运试剂盒及Western blot 检测NF-κB 信号的激活水平。结果:与对照组相比,类风湿关节炎患者PBMCs、血清及滑膜组织和滑膜液中IL-38 水平显著升高,而TLR4 水平也显著升高,Pearson 相关分析显示二者呈负相关。LPS 和/ 或IL-38 刺激RAW264.7 细胞后,IL-38 能够抑制LPS 诱导的TLR4、IL-6、IL-8 及TNF-α表达,进一步的分析显示,IL-38 能抑制NF-κB 信号途径激活,因此推测IL-38 可能是通过抑制NF-κB 信号途径激活从而抑制LPS/ TLR4 信号诱导的炎症因子表达。结论:IL-38 能抑制LPS/ TLR4 诱导炎症减轻类风湿关节炎,其机制可能是通过抑制NF-κB 信号途径的激活。     

Differential effects of IL-10 on prostaglandin H synthase-2 expression and prostaglandin E2 biosynthesis between spleen and bone marrow macrophages

Different populations of mononuclear phagocytes (MO) show considerable diversity of cellular function including prostaglandin E2 (PGE2) biosynthesis. Certain bacterial components enhance PGE2 biosynthesis differentially in selected populations of MO. Interleukin (IL)-10 is proposed to inhibit modulation of PGE2 biosynthesis by down-regulating prostaglandin G/H synthase-2 (PGHS-2) expression. To assess whether IL-10 regulates PGE2 biosynthesis and PGHS-2 expression, splenic and bone marrow MO were isolated from IL-10-deficient (IL-10(-/-)), C57Bl/6 [wild-type (WT) control], and Balb/c (comparison control) mice and were treated with lipopolysaccharide (LPS) and/or interferon-gamma (IFN-gamma) as a model of bacterial inflammation. LPS-induced PGHS-2 expression was similar for splenic MO isolated from the three strains of mice. However, PGE2 released by LPS-treated splenic MO was significantly higher in IL-10(-/-) and Balb/c than in WT cells. In the presence of LPS and IFN-gamma, PGHS-2 expression and PGE2 release by IL-10(-/-) and Balb/c splenic MO were enhanced compared with stimulation with LPS alone or IFN-gamma alone. However, there was no significant increase in PGE2 release from WT splenic MO treated with LPS plus IFN-gamma despite increased PGHS-2 expression. In sharp contrast, PGHS-2 expression and PGE2 release by bone marrow MO were greatly enhanced in IL-10(-/-) cells compared with control cells. Our results indicate that IL-10 regulation of MO PGE2 biosynthesis and PGHS-2 expression is compartment-dependent and that PGE2 production is not linked directly to PGHS-2 levels. Furthermore, our findings emphasize strain-specific differences between C57Bl/6 and Balb/c mice, and Balb/c appears more similar to the IL-10(-/-) than to the C57Bl/6 with respect to prostanoid production.     

Production of interleukin-1 and tumor necrosis factor by bone marrow-derived macrophages: effect of cisplatin and lipopolysaccharide

Mature macrophages derived in vitro from bone marrow progenitors under the influence of either L929 CM (a source of M-CSF) or GM-CSF have been shown to differ morphologically and functionally. Treatment of these bone marrow-derived macrophages with cisplatin or LPS resulted in the expression of enhanced tumoricidal activity and the production of significant amounts of extracellular and membrane-associated IL-1 and TNF. rGM-CSF-derived bone marrow macrophages produced higher amounts of TNF and IL-1 activity than L929CM-derived macrophages. Untreated bone marrow-derived macrophages showed little IL-1 and TNF activity. Bone marrow macrophages cultured with medium alone also did not respond to cisplatin or LPS for the production of IL-1 and TNF. Neutralization studies with anti-IL-1 and anti-TNF antibodies inhibited the IL-1 and TNF activity of bone marrow-derived macrophages. These results suggest that cisplatin or LPS treatment of murine bone marrow-derived macrophages results in increased expression of both released and membrane-associated IL-1 and TNF.     

In vivo effects of bacterial lipopolysaccharide on proliferation of macrophage colony-forming cells in bone marrow and peripheral lymphoid tissues

Changes in the number of macrophage colony-forming cells in various tissues of mice injected with lipopolysaccharide (LPS) from Klebsiella pneumoniae, Escherichia coli, or Salmonella enteritidis were studied. The injection of LPS increased macrophage colony-forming cells in peripheral lymphoid tissues such as the spleen, mesenteric lymph nodes, and regional lymph node, although the same treatment caused the decrease of such cells in the bone marrow. This phenomenon was consistently observed when tested by various LPSs. The injection of LPS into mice which had been exposed to X-ray irradiation and reconstituted with syngeneic normal bone marrow cells decreased colony-forming cells in the spleen. The increase of macrophage colony-forming cells in the spleen seemed, therefore, not to be due to migration from the bone marrow. The injection of LPS appeared to shorten the lag time before the initiation of mitosis of colony-forming cells in the spleen but not in the bone marrow. No participation of serum factors in this phenomenon could be detected. It was suggested that there might be an essential difference between the responsiveness to LPS of macrophage colony-forming cells in the spleen and those of the bone marrow.     

IL-17A 协同GM-CSF 和LPS 促进骨髓细胞衍生树突状细胞的分化和成熟研究

目的:探讨IL鄄17A 对小鼠骨髓细胞衍生树突状细胞分化和成熟的影响。方法:分离小鼠骨髓细胞,加入含GM-CSF(20 ng/ ml)RPMI1640 完全培基培养8 d,诱导小鼠骨髓单个核细胞向DC 分化,加入LPS(1 滋g/ ml)继续培养36 h,进一步诱导DC 成熟,同时在骨髓细胞衍生诱导DC 分化及成熟的不同阶段加入不同浓度的rmIL-17A(10、100 ng/ ml),采用流式细胞术检测DC 表面共刺激分子的表达,ELISA 方法检测DC 培养上清中IL-12p40 和IL-10 水平。结果:rmIL-17A 可促进GM-CSF 诱导骨髓细胞衍生DC 表面共刺激分子CD40、CD80、CD86 和MHC域的表达,且具有剂量依赖性,其中以高浓度rmIL-17A刺激组的CD40 及MHC域表达增加最显著;在LPS 诱导DC 成熟阶段加入rmIL-17A,骨髓细胞衍生DC 共刺激分子CD40、CD80、CD86 和MHC域的表达均明显增加,并且随着rmIL-17A 浓度的增加,CD86 和MHC域的表达水平也随之增高;同时与未加rmIL鄄17A 的对照组相比,低浓度rmIL-17A 组LPS 刺激骨髓细胞衍生DC 分泌IL-12p40 和IL鄄10 水平均显著增加(P <0.001),高浓度rmIL-17A 组IL-12p40 水平显著增高(P<0.001),但IL-10 水平没有变化。结论:IL-17A 可促进GM-CSF 诱导的骨髓细胞衍生DC 前体细胞表型发展,并能协同LPS 诱导骨髓衍生DC 的分化和成熟。     

Early effects of tocilizumab on bone and bone marrow lesions in a collagen-induced arthritis monkey model

To understand the contribution of IL-6/IL-6R to subchondral bone and bone marrow abnormality in RA patients and the effects of tocilizumab on those abnormalities, we evaluated early change in a collagen-induced arthritis (CIA) monkey model with or without a single administration of tocilizumab. Six CIA cynomolgus monkeys received tocilizumab and 3 CIA monkeys received vehicle only. Their interphalangeal joints were analyzed using HE, silver impregnation (SI), or immunohistochemistry (RANKL) staining. The number of osteoclasts increased in the arthritis control but was suppressed in the tocilizumab-treated animals. Osteoblast/stromal cells of the arthritis control monkeys were of monolayer, while in the tocilizumab-treated monkeys, the cells were multi-layer or differentiated osteoblasts, and the meshwork of the reticulum fibers showed recovery in the SI. Hematopoietic marrow was replaced by interstitial fluid and reticulum fibers were eliminated in the arthritic model but showed recovery in the tocilizumab-treated animals. RANKL showed overproduction with arthritis and suppressed with tocilizumab treatment. The evidence indicates that IL-6/IL-6R is involved in subchondral bone and bone marrow change in RA patients. Tocilizumab treatment recovered changes in the CIA monkeys as a result of the co-differentiation between the osteoclasts and the osteoblast/stramal cells, at least partially through the suppression of RANKL overproduction.     

Expression of retrovirally transduced IL-1 alpha in IL-6-dependent B cells: a murine model of aggressive multiple myeloma.

Retroviral-mediated gene transfer was employed to introduce an IL-1 alpha cDNA into an IL-6-dependent murine B-cell line. Bone marrow metastases and bone lesions were frequently observed following intravenous injection of these B cells into syngeneic mice. Because the retroviral vector also contained the neomycin phosphotransferase gene, metastatic cells could be easily recovered from bone marrow by addition of G418 to the culture medium. Interestingly, the metastatic B cells were found to retain their IL-6 dependency through several transplant generations. By comparison, intravenous injection of autonomously-growing B-cell lines generated in vitro by retroviral introduction of an IL-6 cDNA rarely resulted in bone marrow metastases. These results demonstrate that abrogation of growth factor dependency is neither necessary nor sufficient for the in vivo growth and dissemination of tumor cells in this experimental system. It is proposed that the increased metastasis of the IL-1 alpha-producing B-cells to bone marrow is due to alterations in cell adhesion molecules. The B-cell bone marrow metastasis model described here may be useful for studies of bone marrow homing and for evaluation of therapeutic regimens for multiple myeloma.     

Expression of Retrovirally Transduced IL-1 α in IL-6-Dependent B Cells: A Murine Model of Aggressive Multiple Myeloma

Abstract

Retroviral-mediated gene transfer was employed to introduce an IL-1α cDNA into an IL-6-dependent murine B-cell line. Bone marrow metastases and bone lesions were frequently observed following intravenous injection of these B cells into syngeneic mice. Because the retroviral vector also contained the neomycin phosphotransferase gene, metastatic cells could be easily recovered from bone marrow by addition of G418 to the culture medium. Interestingly, the metastatic B cells were found to retain their IL-6 dependency through several transplant generations. By comparison, intravenous injection of autonomously-growing B-cell lines generated in vitro by retroviral introduction of an IL-6 cDNA rarely resulted in bone marrow metastases. These results demonstrate that abrogation of growth factor dependency is neither necessary nor sufficient for the in vivo growth and dissemination of tumor cells in this experimental system. It is proposed that the increased metastasis of the IL-1 α-producing B-cells to bone marrow is due to alterations in cell adhesion molecules. The B-cell bone marrow metastasis model described here may be useful for studies of bone marrow homing and for evaluation of therapeutic regimens for multiple myeloma.