Astragalus membranaceus ; chemistry ; Cell Line ; Cytokines ; metabolism ; Humans ; Inflammation ; Macrophages ; drug effects ; metabolism ; Monocytes ; drug effects ; metabolism ; Polysaccharides ; pharmacology

OBJECTIVETo investigate the influence of microcystin-LR (MC-LR) on monocytes and lymphocytes in blood of mice and to find a sensitive index of toxic effects.

METHODSSpecific pathogen free Kunming male mice, aging 1 month-old,were randomly divided into 5 groups by weights, 7 mice for each group. The mice in 5 groups were exposed to MC-LR through intraperitoneal injection at 0, 3.125,6.250, 12.500 and 25.000 µg/kg respectively for 7 days. Then cytokine levels in the serum were measured by radioimmunoassay, DNA-protein crosslinks (DPC) was measured by the SDS/KCl precipitation technique, and the phagocytosis and ROS of leukocytes were detected by flow cytometry.

RESULTSThe levels of interleukin 6 in the 6.250, 12.500 and 25.000 µg·kg(-1)·d(-1) dose groups were (346.837 ± 25.536), (360.847 ± 37.886) and (434.245 ± 35.858)pg/ml respectively, which were significantly higher than those in the control group which the value was (232.775 ± 32.816) pg/ml (t values were -7.258, -6.760 and -10.966 respectively, P values were all < 0.05).While the level of tumor necrosis factor-alpha was(10.782 ± 0.966) fmol/ml in 25 µg·kg(-1)·d(-1) dose group was statistically lower than it in the control group which the value was (16.878 ± 3.378) fmol/ml (t value was 4.591, P < 0.05). The DPC levels of lymphocytes in 6.250, 12.500 µg·kg(-1)·d(-1) dose group were (242.576 ± 7.545),(241.472 ± 2.793) ng/ml,higher than it in the control group while the value was (228.657 ± 4.130) ng/ml (t value was -4.282, -6.801, P values were all <0.05). The fluorescence intensity of DCF in lymphocytes in the 4 treated groups were separately 3299.37 ± 120.54, 3281.38 ± 58.34, 3308.06 ± 136.12 and 3346.92 ± 108.69, all significantly lower than 3770.81 ± 131.39 in the control group (t values were 6.995, 9.007, 6.472 and 6.577 respectively, and P values were all <0.05). The fluorescence intensity of DCF in monocytes in the 4 treated groups (3271.51 ± 140.79, 3270.05 ± 117.92, 3326.90 ± 114.39 and 3292.49 ± 145.97 respectively) were also significantly lower than the value in the control group was 3841.72 ± 130.92 (t values were 7.847, 8.584, 7.835 and 7.411 respectively, P values were all <0.05). There was no significant difference in other index among the four experiment groups and the control group.

CONCLUSIONThe MC-LR administered via intraperitoneal injection to mice induced the alterations of some cytokines of monocytes and lymphocytes in blood. By comparison, the ROS of leukocyte was the most sensitive index.

Animals ; Cytokines ; metabolism ; Lymphocytes ; drug effects ; Male ; Mice ; Mice, Inbred Strains ; Microcystins ; pharmacology ; Monocytes ; drug effects ; Reactive Oxygen Species ; metabolism

This study was aimed to explore the killing effect of PBMNC induced by IL-23 alone or combined with IL-2 on K562 cells and its mechanism. The PBMNC were induced in vitro by IL-23 (50 ng/ml) alone or IL-23 combined with IL-2 (100 U/ml) for 72 h, and then were co-cultured with leukemia cell line K562. The CCK-8 method was used to detect the effect of PBMNC induced at different times on K562 cells, the ELISA was performed for detecting IFN-γ level in culture supernatant, and the perforin and granzymes B were detected by RQ-PCR. The results showed that the killing effect of PBMNC induced by IL-23 alone or IL-23 combined with IL-2 on K562 cells was observed, and obviously enhanced with prolonging of time, moreover, there was statistical difference among different time points (P < 0.05). The IFN-γ level in supernatant of PBMNC cultured with cytokines significantly increased, and the IFN-γ levels in group of IL-23 combined with IL-2 were higher than that in other groups (P < 0.05). The mRNA expressions level of perforin and granzymes B of the expanded PBMNC in groups cultured with cytokines were higher than that in control group (P < 0.05), and the mRNA expressions of perforin and granzymes B in group of IL-23 combined with IL-2 were significantly higher than that in others (P < 0.05). It is concluded that IL-23 can promote the killing effect of PBMNC on K562 cells. The combination of IL-2 with IL-23 displays synergic effect and a time-dependent manner. IL-23 also enhances the expression of IFN-γ, perforin and granzyme B in PBMNC. Its combination with IL-2 displays synergistic effect, suggesting that the anti-leukemic activity of IL-23 may be realized through inducing PBMNC to express IFN-γ, perforin and granzyme B.
Granzymes ; metabolism ; Humans ; Interferon-gamma ; metabolism ; Interleukin-2 ; pharmacology ; Interleukin-23 ; pharmacology ; K562 Cells ; Monocytes ; drug effects ; metabolism ; Perforin ; metabolism

The immunocytes microglia in the central nervous system (CNS) were reported to play a crucial role in neurodegeneration. As a member of P2 receptors family, purinoceptor P2Y6 has attracted much attention recently. Previous studies showed that purinoceptor P2Y6 mainly contributed to microglia activation and their later phagocytosis in CNS, while in immune system, it participated in the secretion of interleukin (IL)-8 from monocytes and macrocytes. So there raises a question: whether purinoceptor P2Y6 also takes part in neuroinflammation? Thus, this review mainly concerns about the properties and roles of purinoceptor P2Y6, including (1) structure of purinoceptor P2Y6; (2) distribution and properties of purinoceptor P2Y6; (3) relationships between purinoceptor P2Y6 and microglia; (4) relationships between purinoceptor P2Y6 and immunoinflammation. Itos proposed that purinoceptor P2Y6 may play a role in neuroinflammation in CNS, although further research is still required.
Animals ; Humans ; Inflammation ; immunology ; metabolism ; Microglia ; drug effects ; metabolism ; Monocytes ; metabolism ; Phagocytosis ; physiology ; Receptors, Purinergic P2 ; chemistry ; genetics ; metabolism

OBJECTIVEDendritic cells an hyperinsulinemia are both implicated in the pathogenesis of atherosclerosis. The aim of this study is to explore the effect of high concentration of insulin on the maturation of monocyte-derived dendritic cells (MoDCs) and related signal transduction pathways.

METHODSHuman monocytes were purified (over 98%) using Anti-CD14 micro-beads and cultured for 5 days with DC Cellgro medium containing rhGM-CSF (100 microg/L) and rhIL-4 (20 microg/L). Immature DC were then incubated with insulin of various concentrations (0, 1, 10, 100 nmol/L) for 24 hours in the presence or absence of LY294002 (PI3K inhibitor) or PD98059 (MAPK inhibitor). Immunophenotypic expression of CD86 and CD83 were detected using flow cytometry. Endocytosis function of the MoDCs was evaluated using FITC-Dextran and MoDCs secretion IL-12, IFN-gamma and TNF-alpha were measured by ELISA.

RESULTSInsulin induced significantly higher CD83 and CD86 expressions on MoDCs in a dose-dependent manner. The endocytosis function of MoDCs were significantly inhibited and cytokine secretions of IL-12, IFN-gamma and TNF-alpha significantly increased by 10 nmol/L and 100 nmol/L insulin. These effects could be blocked by the LY294002 and PD98059.

CONCLUSIONHyperinsulinemia contributed to atherosclerosis via stimulating immune maturation of MoDCs via both PI3K and MAPK pathways.

Cell Differentiation ; drug effects ; immunology ; Cells, Cultured ; Cytokines ; metabolism ; Dendritic Cells ; drug effects ; immunology ; metabolism ; Humans ; Insulin ; administration & dosage ; pharmacology ; Monocytes ; cytology ; Phagocytosis ; drug effects ; Signal Transduction

OBJECTIVETo explore the putative effects of Vitamin C (Vit C) on inhibition of human leucocyte antigen class I (HLA-I) expression of human peripheral blood mononuclear cells (HPBMCs) induced by deoxynivalenol (DON) in vitro.

METHODSThe effects of Vit C on the changes of HLA-I expression of HPBMCs induced by DON in vitro were evaluated with cell culture, flow cytometry (FCM), Western blotting and immunocytochemical methods.

RESULTSFCM analysis showed that HLA-I expression of HPBMCs in DON treated cells was significantly lower than that in controls (FI 0.88 +/- 0.02 vs 1.00 +/- 0.03, P < 0.05). As compared with DON group, the HLA-I expressions of HPBMCs in the two Vit C (25 micromol/L and 100 micromol/L) pretreatment groups were all significantly increased (1.15 +/- 0.06 and 1.10 +/- 0.02 vs 0.88 +/- 0.02, P < 0.05). Exposure to different dosage of Vit C alone could dramatically increase the expression of HLA-I of HPBMCs in vitro as compared with that in the normal control (FI for 25 micromol/L and 100 micromol/L Vit C treatment group was 1.28 +/- 0.03 and 1.25 +/- 0.05 respectively, P < 0.05). Immunocytochemical results showed that the percentages of HLA-I positive expression of HPBMCs in Vit C pretreatment groups at different dosages were significantly higher than those in DON group (70.10 +/- 6.90)%, (64.50 +/- 5.50)% vs (42.20 +/- 4.30)%, P < 0.05. Western blotting confirmed the results of FCM and immunocytochemistry.

CONCLUSIONSVitamin C pretreatment at different dosages could reverse at some extent the inhibitive effects of DON on HLA-I expression of HPBMCs.

Ascorbic Acid ; pharmacology ; Cells, Cultured ; Flow Cytometry ; Histocompatibility Antigens Class I ; metabolism ; Humans ; Monocytes ; drug effects ; metabolism ; Trichothecenes ; pharmacology

OBJECTIVETo study the effects of Lipopolysaccharide (LPS) on the maturation and secretion of human peripheral dendritic cells (DCs).

METHODSDCs from healthy human peripheral monocytes (PBMCs) were induced in vitro with rhGM-CSF, rhIL-4, Flt3-L and TNFalpha. The subjects were divided into 3 groups: the long-term group stimulated with LPS 1 microg/ml at day 1, 4, 7, 9 post culture; the short-term group stimulated with LPS 1 microg/ml at day 7 and 8 post culture, and the DCs without LPS stimulation was control group. After 10 days of culture, the morphologic features of DCs were observed by light and electron microscopes, the phenotypic patterns were characterized by flow cytometry, the proliferation of T cell were evaluated with mixed leukocytes reaction (MLR) and the levels of IL-12 and IFNgamma produced by DCs were analyzed with ELISA.

RESULTSCompared with the short-term group, the expressions of HLA-DR (65.81%+/-10.96%), CD86 (48.81%+/-18.13%), CD80 (13.56%+/-5.48%), CD83 (11.52%+/-5.09%), the secretions of IFNgamma(15.60+/-5.83 pg/ml) and IL-12 (51.77+/-11.02 pg/ml) by the DCs in long-term group were decreased obviously (P is less than 0.05) and the proliferation of homogenic lymphocyte cells (1.548+/-0.365) stimulated by DCs was also impaired (P < 0.05).

CONCLUSIONLong-term LPS stimulation can suppress the maturation and secretion of DCs, which might be the reason of poor immunity in the patients with intestinal endotoxemia.

Cells, Cultured ; Dendritic Cells ; cytology ; drug effects ; metabolism ; Humans ; Interleukin-12 ; biosynthesis ; Lipopolysaccharides ; pharmacology ; Monocytes ; cytology ; metabolism

OBJECTIVETo investigate the effect of folic acid on homocysteine (Hcy)-induced chemokine secretion and NADPH oxidase activity in human monocytes.

METHODSHuman monocytes from healthy volunteers were incubated with Hcy (100 micromol/L) with or without folic acid (5 micromol/L) for 24 h; MCP-1 and IL-8 were assessed by ELISA. DCFH-DA was added to monitor intracellular ROS production on confocal microscopy. A cytochrome c reduction assay was used to measure NADPH oxidase activity.

RESULTSThe Hcy-induced secretion of MCP-1 and IL-8 was significantly reduced by folic acid [(1.88 +/- 0.51) ng/ml vs. (4.36 +/- 0.72) ng/ml vs. (2.40 +/- 0.60) ng/ml and (4.9 +/- 1.9) ng/ml vs. (12.7 +/- 1.5) ng/ml vs. (7.2 +/- 1.9) ng/ml, all P < 0.05]. The Hcy-induced production of ROS was also significantly attenuated by folic acid. Moreover, the Hcy-induced NADPH oxidase activity increase was significantly inhibited by cotreatment with folic acid.

CONCLUSIONFolic acid may attenuate oxidative stress induced by Hcy by reducing NADPH oxidase activity in monocytes.

Cells, Cultured ; Chemokines ; secretion ; Folic Acid ; pharmacology ; Homocysteine ; pharmacology ; Humans ; Interleukin-8 ; metabolism ; Monocytes ; drug effects ; secretion ; NADPH Oxidases ; metabolism ; Oxidative Stress ; drug effects ; Receptors, CCR2 ; metabolism

OBJECTIVESerum pregnancy-associated plasma protein A (PAPP-A) is increased in acute coronary syndrome patients and related to prognosis. We investigated the effects of C-reactive protein (CRP) and tumor necrosis factor-alpha (TNF-alpha) on PAPP-A mRNA expression in monocytes.

METHODSMonocytes were isolated by Ficoll density gradient centrifugation from blood of healthy volunteers. The PAPP-A expressions at mRNA level post CRP or rhTNF-alpha stimulation were measured by RT-PCR.

RESULTSPAPP-A mRNA expression in peripheral blood monocytes increased 2 hours (0.2128 +/- 0.0136) and peaked 24 hours (0.6837 +/- 0.1360) after CRP (20 mg/L) stimulation compared with control group (0.1842 +/- 0.0101). PAPP-A mRNA expression increased rapidly, peaked 2 hours (1.2546 +/- 0.0866) and remained elevated up to 24 hours (0.8203 +/- 0.0413) after rhTNF-alpha (100 ng/ml) stimulation. The effects of CRP and TNF-alpha were dose-dependent. PAPP-A mRNA expression of monocytes were 0.2544 +/- 0.0611, 0.4177 +/- 0.1200, 0.5828 +/- 0.0152, 0.6837 +/- 0.1360 after stimulated with CRP (1, 5, 10, 20 mg/L), and 0.2424 +/- 0.1378, 0.3335 +/- 0.0196, 0.5742 +/- 0.0131, 0.6913 +/- 0.0219 and 0.8203 +/- 0.0413 after stimulated with rhTNF-alpha (5, 10, 25, 50 and 100 ng/ml). Actinomycin D, the DNA-directed RNA polymerase inhibitor, completely blocked CRP and TNF-alpha induced PAPP-A expression.

CONCLUSIONSPAPP-A mRNA expression could be stimulated by CRP and TNF-alpha in human peripheral blood monocytes which might be responsible for the increased serum PAPP-A level in patients with acute coronary syndromes.

C-Reactive Protein ; adverse effects ; pharmacology ; Cells, Cultured ; Humans ; Monocytes ; drug effects ; metabolism ; Pregnancy-Associated Plasma Protein-A ; metabolism ; RNA, Messenger ; metabolism ; Tumor Necrosis Factor-alpha ; pharmacology

The study was aimed to investigate the mechanism of mannan-binding lectin (MBL) on bacterial lipopolysaccharide (LPS)-induced human peripheral blood monocyte-derived dendritic cell (DC) maturation. The monocytes were prepared from the peripheral blood of healthy adult volunteers. The immature dendritic cells (imDC) were induced by 5-day-culture in medium supplemented with rhGM-CSF and rhIL-4. FACS was used to investigate the interaction of MBL with imDC and the impact of MBL on LPS binding to imDC. ELISA and Western blot was used to analyze the interaction of MBL with soluble TLR4 ectodomain protein (sTLR4); Western blot was used to detect LPS-induced NF-κB translocation in imDC. The results showed that MBL could directly bind to imDC in the presence of calcium. sTLR4 protein or LPS could competitively inhibit the binding of MBL to imDC. ELISA and Western blot showed that MBL could evidently bind to sTLR4 protein in a concentration-dependent manner. FACS showed that MBL could competitively inhibit the binding of LPS to imDC by binding to imDC directly. Western blot showed that MBL decreased LPS-induced NF-κB translocation in imDC. It is concluded that MBL may competitively inhibit the binding of LPS to imDC by binding to TLR4 expressed on imDC, resulted in inhibition of LPS-induced DC maturation, suggesting that MBL can regulate DC maturation through ligand-binding. This study provides the good foundation to clarify the mechanism of MBL inhibiting the LPS-induced DC maturation.
Cell Differentiation ; Cells, Cultured ; Dendritic Cells ; cytology ; drug effects ; metabolism ; Humans ; Ligands ; Lipopolysaccharides ; adverse effects ; Mannose-Binding Lectin ; pharmacology ; Monocytes ; cytology ; metabolism ; Toll-Like Receptor 4 ; metabolism