The immunity effect of B7-H1 blockade on immature dendritic cells

AIM: To investigate the immune stimulation capacity of B7-H1 blockade on immature dendritic cells (DCs) in vitro. METHODS: The human monocyte-derived dendritic cells were induced in the presence of cytokine GM-CSF and IL-4. The expression of B7-H1 was detected by FCM. On blockade of B7-H1, the maturation and endocytic activity, T cells stimulatory proliferation capacity, IL-12 production, T cell differentiation effect of DCs were detected by FCM, MTT assay, ELISA and ELISPOT, respectively. RESULTS: The expression of B7-H1 was increased with the induction of DCs. On day 7, the positive expression was 54.12%, and the TNF-α induced mature DCs had the positive expression rate of 83.64%. The blockade of B7-H1 on immature DCs had sharply increased their T cells stimulatory proliferation capacity and IL-12 production, and efficiently induced the development of Th1/Tc1 cells, but had no effect on their maturation and endocytic activity. CONCLUSION: The blockade of B7-H1 on immature DCs increases its immune stimulation activity. It is valuable to investigate the antitumor immune responses of DCs vaccine with B7-H1 blockade.     

Effects of progesterone on the maturation and immunologic function of dendritic cells from human peripheral blood

AIM: To study the effects of progesterone (P₄) on the maturation and immunologic function of dendritic cells (DCs) from human peripheral blood. METHODS: Cultured DCs were treated with P₄ at doses of 10-7 mol/L and 10-6 mol/L. The morphologic changes were observed under the scanning electronic microscope. The immunophenotypes of DCs in control and treated groups were analyzed by flow cytometry. IL-10 and IL-12 production in culture supernatant was examined by ELISA assay. The capability of the stimulatory activity of the DCs on allogeneic T cells in mixed reaction was tested by incorporation of ［3H］-TdR. RESULTS: Compared with control group, cultured DCs in the presence of P₄ displayed less dendritic pseudopod, expressed low levels of MHC-II, CD40, CD80 and CD86, and exhibited weakly activity in stimulating the proliferation of allogeneic T cells. Increase in IL-10 production and decrease in IL-12 production were observed. CONCLUSION: P₄ exerts negative effect on the maturation and immunologic function in dendritic cells from human peripheral blood.     

Effects of 17β-estradiol on the maturation and immunologic function of dendritic cells from human peripheral blood

AIM: To investigate the effects of 17β-estradiol (E2) on the maturation and immunologic function of dendritic cells from human peripheral blood. METHODS: Cultured DCs were treated with E2 at doses of 10-7 mol/L and 10-6 mol/L. The morphologic changes were observed under the scanning electronic microscope. The immunophenotype of DCs in control and treated groups was analyzed by flowcytometry. IL-12 production in culture supernatant was examined by ELISA assay. The capability of the stimulatory activity of the DCs on allogeneic T cells in mixed reaction was tested by incorporation of ［3H］-TdR. RESULTS: Compared with control group, DCs cultured in the presence of E2 displayed less dendritic pseudopod, expressed low levels of MHC-II, CD40, CD80 and CD86, and exhibited weakly activity in stimulating the proliferation of allogeneic T cells and reduction of IL-12 production. CONCLUSION: E2 exerts a negative effect on the maturation and immunologic function of dendritic cells from human peripheral blood.     

Study on the immunological function of sodium butyrate-induced immature human monocyte-derived dendritic cells

AIM: To investigate the immunological function of sodium butyrate-induced immature dendritic cells in vitro.METHODS: The human monocyte-derived dendritic cells were induced in the presence of human granulocyte macrophage-colony stimulating factor(GM-CSF) and interleukin-4 (IL-4), combined with sodium butyrate. The immunological function of sodium butyrate-induced dendritic cells was detected by the FCM, endocytic activity, T cells stimulatory proliferation capacity, and interleukin-12 (IL-12) production.RESULTS: Sodium butyrate could down-regulate the major histocompatibility complex(MHC) class II and costimulatory molecules of dendritic cells, increase the endocytic activity, induce a stage of T-cell anergey, and inhibit the T helper cell type 1-skewing factor IL-12 production. CONCLUSION: Sodium butyrate inhibits the maturation of dendritic cells and induces production of immature dendritic cells, which may help to explore the machenism of its epigenitic modification.     

Effect of monoclonal antibody to CD47 molecule on dendritic cell differentiation and function

AIM: To explore the influence of CD47 molecules on the maturation and function of cultured dendritic cells (DCs). METHODS: Monocyte cell-derived DCs were propagated in granulocyte-macrophage colony-stimulating factor (GM-CSF) and lipopolysaccharide (LPS) plus interleukin (IL)-4, in the presence or absence of anti CD47 monoclonal antibodies (anti-CD47 mAbs). Flow cytometry was used to detect the cell surface phenotype. The concentration of IL-12P70 in supernatant was measured by ELISA technique. The antigen-presenting functions of DCs were determined in one-way mixed leukocyte reaction by Brdu-ELISA. Electrophoretic mobility shift assays (EMSA) was used to examine NF-κB activity. RESULTS: The anti-CD47 mAbs markedly suppressed the expression of CD80,CD86,CD83,CD1a,HLA-DR on the surface of DCs (P＜0.05). The data of mixed leukocyte reaction and IL-12P70 production were consistent with the flow cytometry results (P＜0.01). Nuclear extracts from the anti-CD47 mAb-treated DCs revealed a decrease in NF-κB binding activity. CONCLUSION: The anti-CD47 mAb exerts a negative effect on the maturation and function of in vitro cultured DCs via inhibiting of NF-κB binding activity.     

A dynamic observation on the levels of TNF-α、IL-6 and IFN-γ produced by human dendritic cells infected with Dengue virus

AIM: To study the dynamic levels of tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and gamma interferon （IFN-γ） produced by human dendritic cells infected with Dengue virus. METHODS: Monocytes isolated from healthy human peripheral blood were incubated in medium with GM-CSF and IL-4 for more than 7 days. DCs were then collected and identified by scanning electron microscope, immunohistochemistry and lymphocytes stimulatory ability. Human dendritic cells （DC) were infected with Dengue-2 virus (DV-2) in vitro， culture supernatants were collected in different time postinfection (6 h, 12 h, 24 h, 48 h and 72 h)， DV antigen in human dendritic cells were demonstrated by an indirect immunofluorescent assay （IFA）, production of TNF-α, IL-6 and IFN-γ in the culture supernatants were evaluated by ELISA. RESULTS: After 7 days, typical dendritic cells could be obtained. Virus antigen were detected in infected DC by IFA. Dengue virus induces TNF-α and IL-6 secretion from DC and does not induce IFN secretion. CONCLUSION: Human dendritic cells are target of dengue virus infection. TNF-α， IL-6 production from DC are increased with DV infection. Dendritic cells may play an important role in DV pathogenicity and immunity.     

Effect of glucocorticoid-treated dendritic cells on asthmatic Th2 response

AIM: To investigate the effect of dexamethasone-treated dendritic cells (DCs) on Th2 cytokine production from autologous T cells in asthmatic patients and explore the mechanisms by studying the effect of dexamethasone on differentiation, maturation and function of DCs from patients with asthma. METHODS: Human peripheral blood monocyte-derived DCs generated from asthmatic patients and healthy subjects were cultured in the absence or presence of dexamethasone. The phenotypic characterization of DCs was analyzed by flow cytometry. The mature DCs were harvested, washed, and then cocultured in vitro with autologous T cells purified by a nylon cotton column. The DC-T coculture supernatants were collected after 72 h incubation and analyzed for levels of IL-5 and IFN-γ by ELISA. RESULTS: The concentrations of IL-5 in the culture supernatants of DC-T coculture were significantly up-regulated in patients with asthma compared with that in healthy controls ［(145.13±89.76) ng/L vs (50.28±22.37) ng/L, P<0.01］. The level of IFN-γ in the DC-T coculture supernatants tended to be decreased in asthmatic patients than that in healthy controls, although this difference did not achieve statistical significance ［(197.58±76.32) ng/L vs (220.46±65.34) ng/L, P>0.05)］. There were significantly decreased levels of IL-5 by autologous T cells primed by dexamethasone-treated mature DCs from asthmatic patients ［(45.39±19.61) ng/L vs (145.13±89.76) ng/L, P<0.01］, alterations not observed from healthy controls (P>0.05). IFN-γ production was decreased by autologous T cells primed by dexamethasone-treated mature DCs from both asthmatic patients and healthy controls ［asthma group: (40.21±22.89) ng/L vs (197.58±76.32) ng/L, P<0.01; healthy controls: (56.78±20.37) ng/L vs (220.46±65.34) ng/L, P<0.01］. Dexamethasone-treated DCs exhibited decreased expression of CD83 (P<0.01) and increased expression of CD14 (P<0.01) in both asthmatic patients and healthy controls. CONCLUSION: DCs of asthmatic patients induce a Th2-skewed cytokine production from autologous T cells. Dexamethasone-treated DCs inhibit the Th2 reactions, and this effect is probably mediated through the pathway that dexamethasone inhibits DCs maturation and skews the macrophage/DC balance towards the macrophage side and thus directs the development more towards the macrophage lineage.     

Effects of interferon-γ, tumor necrosis factor-α and interleukin-1β on apoptosis of human airway smooth muscle cellsin vitro

AIM:To clarify if interferon-γ(IFN-γ), tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)can induce apoptosis of human airway smooth muscle cells (ASMCs) in vitro.METHODS:Human ASMCs were isolated and cultured in DMEM containing 10% fetal bovine serum. Passage 4-6 cell was used in the experiment. IFN-γ,TNF-α and IL-1β, were used separately or together in the treatment of human ASMCs. The effects of IFN-γ,TNF-α and IL-1β on the growth of the cells was detected by MTT method at the hour 0,24,48 and 72. Light microscopy and electron microscopy were used to examine the morphological change. DNA fragmentation was analyzed by agarose gel electrophoresis. SP immunohistological staing method was performed to detect the change of expressions of p 53, bcl- 2 and bax gene. The apoptosis cell percentage were detected by in situ end labeling technique (TUNEL)of fragmental DNA. RESULTS:(1)IFN-γ or IFN-γ together with TNF-α and IL-1β decreased the number of viable cells in a time dependent manner. (2) Light and electron microscopic examination showed cell shrinkage, membrane blebbing, nuclear contraction, chromatin condensation and nuclear fragmentation in human ASMCs. (3) Agarose gel electrophoresis showed a characteristic"ladder"of DNA bands representing integer multiples of the internucleosomal fragments (about 180-200 bp) in cytokine cotreated human ASMCs. (4)The expression of p 53 and bax gene in cytokine cotreated group was significantly higher than in control group, but the expression of bcl-2 gene was lower than in control group. (5)Stimultaneous treatment with IFN-γ(4×10⁵ U/L),TNF-α(4×10⁵ U/L)and /or IL-1β (10×10⁴ U/L) induced apoptosis of human ASMCs. Apoptotic index of human ASMCs in cytokine co-treated group was significantly higher than in control group (P＜0.01).CONCLUSION:Stimultaneous treatment with IFN-γ,TNF-α and /or IL-1β induced apoptosis of human ASMCs. These immune cytokines may play an important role in airway remodeling of asthma and of chronic obstructive pulmonary disease.     

Influence of stimulation by LPS and CD40 ligandization in vitro on the TLR4-MD2 expression and IL-12 production in DCs modified by sCD40 gene

AIM: To study the influence of stimulation by LPS and CD40 ligandization in vitro on the TLR4-MD2 expression and IL-12 production in dendritic cells (DCs) modified by sCD40 gene and provide the experimental clues of inducing dornor-specific immune tolerance.METHODS: Plasmid pEGFP-N1/sCD40 and pEGFP-N1 was transfected into DC2.4 cell line with lipofectamine.After 6 h of treatment with LPS and anti-CD40mAb,the expression of TLR4-MD2 on DCs was determined with flow cytometry (FCM) and RT-PCR.IL-12p70 protein was detected by ELISA.RESULTS: LPS treatment of DCs down-regulated surface expression of TLR4-MD2,LPS treatment along with anti-CD40mAb significantly up-regulated TLR4-MD2 surface expression.CD40 ligandization did not affect TLR4-MD2 mRNA expression in DCs but partly increased its low level induced by LPS and markly enhanced IL-12p70 secretion after LPS stimulation.DCs modified by sCD40 gene inhibited the above effect.CONCLUSION: After treatment with LPS and anti-CD40mAb,DCs modified by sCD40 gene down-regulate surface expression of TLR4-MD2 and IL-12p70 secretion decreases significantly,which might be linked with the interruption of TLR4-MD2 transportation from cytoplasm.     

Effect of recombinant rat CC16 protein on LPS-induced expression of TNF-α, IL-6 and IL-8 in rat tracheal epithelial cells

AIM: To explore the effect of recombinamt rat CC16 protein (rCC16) on LPS-induced expression of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-8 in the rat tracheal epithelial (RTE) cells.METHODS: The RTE cells were incubated with rCC16 at concentrations of 0.5, 1.0 and 2.0 mg/L in serum-free media for 2 h prior to LPS (0.1 mg/L) treatment for further 24 h. The cells were harvested for assessing the mRNA levels of TNF-α, IL-6 and IL-8 by RT-qPCR. The cell culture supernatants were collected for analyzing the protein levels of TNF-α, IL-6 and IL-8 by ELISA. In addition, the nuclear translocation of nuclear factor-κB (NF-κB) p65 was tested by Western blot.RESULTS: rCC16 inhibited LPS-induced IL-6 and IL-8 expression at both mRNA and protein levels in the RTE cells in a concentration-dependent (0~2 mg/L) manner, as demonstrated by RT-qPCR and ELISA. However, no concentration-dependent manner between the dose of rCC16 and TNF-α expression was observed, and rCC16 inhibited LPS-induced TNF-α expression at lower concentration (0.5 mg/L). rCC16 concentration-dependently inhibited the effects of LPS on the level of nuclear translocation of NF-κB p65.CONCLUSION: rCC16 suppresses LPS-mediated TNF-α, IL-6 and IL-8 production through inactivation of NF-κB activity in RTE cells.[KEY WORDS] CC16 protein; Airway inflammation; LPS; Inflammatory mediators; Nuclear factor-κB     

TGF β1 inhibits the maturation of dendritic cells and down-regulates TLR4 expression

AIM: To investigate the effects of transforming growth factor β1 (TGF-β1) on murine-derived dendritic cells (DC). METHODS: Murine bone marrow cells were cultured with GM-CSF and TGF-β1 to develop TGF β-DC. Then they were stimulated by lipopolysaccharide (LPS). Their phenotypes were assessed by flow cytometry (FCM). The allogeneic stimulating capacity of DC was measured by mixed lymphocyte reaction (MLR) using BrdU ELISA method. IL-12 p70 protein was detected by ELISA and the expressions of Toll like receptor 4 (TLR4) on DCs were measured by semi-quantitative RT-PCR and FCM. RESULTS: Compared to immature DC (imDC) cultured with GM-CSF alone, the expressions of CD80, CD86, I-Ab and CD40 in TGF β-DC were lower. The TGF β-DC was resistant to maturation by LPS. Maturation resistance was evident from a failure to up-regulate CMs, to stimulate larger T cell proliferation and to increase secretion of IL-12 p70. Down-regulation of TLR4 expression on TGF β-DC was also found. CONCLUSION: TGF-β1 inhibits the expression of co-stimulatory molecules on DC. It is resistant to maturation stimulus (LPS) and might be linked with TLR4 down-regulation.     

Effects of miR-155 over-expression on expression of inflammatory factors and indolamine 2, 3-dioxygenase in microglial BV-2 cells

AIM:To explore the effect of microRNA-155(miR-155)over-expression on the expression of inflammatory factors and indolamine 2, 3- dioxygenase (IDO) in the microglial BV-2 cells. METHODS:For over-expression of miR-155, the BV-2 cells were transfected with lentiviral vector carrying mmu-miR-155. The expression of inflammatory factors was detected by cytometric bead array system (CBA). The mRNA expression of inflammatory factors and IDO was analyzed by real-time PCR. The protein levels of suppressor of cytokine signalling 1 (SOCS1), p-p38 MAPK and IDO were determined by Western blot. RESULTS:The expression of miR-155 was up-regulated in the BV-2 cells transfected with lentiviral vector carrying mmu-miR-155 compared with LPS treatment group (P<0.01). The miR-155 over-expression promoted the secretion of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1) and IL-10, and inhibited the secretion of IL-12. The miR-155 over-expression increased the mRNA expression of IL-6, TNF-α, IL-10 and IDO, also increased the protein levels of IDO and p-p38 MAPK, but decreased the protein expression of SOCS1 (P<0.01). LPS promoted the secretion of IL-6, TNF-α, MCP-1 and IL-12, also increased the mRNA expression of IL-6, TNF-α and IDO, meanwhile, increased the protein levels of IDO, p-p38 MAPK and SOCS1 (P<0.01). CONCLUSION:Over-expression of miR-155 promotes the secretion of related imflammatory factors and protein expression of IDO in microglial BV-2 cells mediated with SOCS1 and p38 MAPK signaling pathway.     

Therapeutic effect of Jiawei Danzhi Xiaoyao powder combined with intravenous human umbilical cord mesenchymal stem cells on post-stroke depression

AIM: To observe the clinical therapeutic effect of Jiawei Danzhi Xiaoyao powder combined with transplantation of human umbilical cord mesenchymal stem cells (HUC-MSCs) in the treatment of post-stroke depression (PSD) patients and to detect the changes of the serum cytokine levels of the tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, norepinephrine (NE), 5-hydroxytry-ptamine (5-HT) and brain derived neurotrophic factor (BDNF). METHODS: The patients with PSD (n=60) were randomly divided into observation group and control group. The patients in observation group was given Jiawei Danzhi Xiaoyao powder combined with HUC-MSCs, and the patients in control group was given Jiawei Danzhi Xiaoyao powder combined with fluoxetine. The course of treatment was 8 weeks. The effects of the treatments on the patients were evaluated with Hamilton Depression Scale (HAMD). The serum levels of IL-1β, IL-6, TNF-α, 5-HT, NE and BDNF were measured by ELISA. RESULTS: After 8 weeks of treatment, the total effective rate in observation group was significantly higher than that in control group (P<0.05). Compared with the same group before treatment, the HAMD scores and the serum levels of TNF-α, IL-1β, IL-6 of the 2 groups were significantly decreased after treatment (P<0.05), while 5-HT, NE and BDNF were significantly increased (P<0.05). After 8 weeks of treatment, the HAMD scores in observation group was significantly lower than that in control group (P<0.05), and the serum levels of TNF-α, IL-1β, IL-6 were significantly decreased in observation group (P<0.05), while 5-HT, NE and BDNF were significantly increased (P<0.05). CONCLUSION: Jiawei Danzhi Xiaoyao powder combined with human umbilical cord mesenchymal stem cells is effective in the treatment of post-stroke depression. The mechanism may be related to the effects of HUCMSCs such as anti-inflammatory effect, increased release of monoamine neurotransmitters, and stimulation of secretion of neurotrophic factors in the brain.     

Effects of NF-κB "decoy" oligodeoxynucleotides on TNF-α and IL-6 expression in LPS-induced mouse macrophages

AIM: To study the effect of NF-κB "decoy" oligodeoxynucleotides on TNF-α and IL-6 expression in LPS-induced mouse macrophages. METHODS: Mouse macrophage cell line J774.1 cells were cultured with LPS and liposome-mediated oligodeoxynucleotides, and the levels of TNF-α and IL-6 measured in the different culture supernatant by enzyme linked immunosorbent assay. RNA was extracted from macrophages, and the mRNA expression of TNF-α and IL-6 in macrophages was observed by RT-PCR. RESULTS: NF-κB "decoy" oligodeoxynucleotides decreased the expression of TNF-α and IL-6 in LPS-induced macrophages and inhibited generation of TNF-α and IL-6. The level of TNF-α and IL-6 did not change in control group. CONCLUSIONS: NF-κB "decoy" oligodeoxynucleotides inhibit the expression of TNF-α and IL-6 in LPS-induced macrophages, which is probably due to the specific inhibition of activated NF-κB binding sites .     

Effects of oxidized low density lipoprotein and vitamin E on the levels of IL-6,IL-8 and TNF-α in cultured human umbilical vein endothelial cells

AIM:To investigate effects of OX-LDL and VitE on the levels of IL-6,IL-8 and TNF-α in human umbilical vein endothelial cells(HUVEC).METHODS: Human umbilical vein endothelial cells were obtained by in vitro culture. HUVEC treated with or without Vit E was incubated with OX-LDL, and the levels of IL-6, IL-8 and TNF-α were determined by enzyme-linked immunosorbent assy technique. RESULTS:50 μg/L,100 μg/L, 200 μg/L OX-LDL induced the release of IL-6,IL-8 and TNF-α by HUVEC in a dose-dependent manner. Compared with the control group , the levels of IL-6 and IL-8 were significantly increased at 6-12 h of stimulation with OX-LDL . Maximal levels of IL-6 and IL-8 occurred after 24-36 h, reaching a plateau maintained for at least 48 h. TNF-α rose after 2-6 h in HUVEC, and reached a maximum after 12 h. In contrast to IL-6 and IL-8, TNF-α declined after 48 h. However, when VitE (50 mg/L,100 mg/L,200 mg/L)was added, it can significant inhibited the release of IL-6, IL-8 and TNF-α in a dose-dependent manner, and after 48 h these cytokines have no diference between OX-LDL+VitE groups and OX-LDL groups. CONCLUSION: OX-LDL can obviously stimulate the production of IL-6,IL-8 and TNF-α in vascular endothelial cells, which can significantly be inhibited by VitE in a short time.