学科分类
/ 1
5 个结果
  • 简介:AbstractBackground:TOSO, also named Fas inhibitory molecule 3 (FAIM3), has recently been identified as an immunoglobulin M (IgM) Fc receptor (FcμR). Previous studies have shown that TOSO is specifically over-expressed in chronic lymphocytic leukemia (CLL). However, the functions of TOSO in CLL remain unknown. The B-cell receptor (BCR) signaling pathway has been reported to be constitutively activated in CLL. Here, we aimed to investigate the functions of TOSO in the BCR signaling pathway and the pathogenesis of CLL.Methods:We over-expressed TOSO in B-cell lymphoma cell lines (Granta-519 and Z138) by lentiviral transduction and knocked down TOSO by siRNA in primary CLL cells. The over-expression and knockdown of TOSO were confirmed at the RNA level by polymerase chain reaction and protein level by Western blotting. Co-immunoprecipitation with TOSO antibody followed by liquid chromatography coupled with tandem mass spectrometry (IP/LCMS) was used to identify TOSO interacting proteins. Western blotting was performed to detect the activation status of BCR signaling pathways as well as B-cell lymphoma 2 (BCL-2). Flow cytometry was used to examine the apoptosis of TOSO-over-expressing B lymphoma cell lines and TOSO-down-regulated CLL cells via the staining of Annexin V and 7-AAD. One-way analyses of variance were used for intergroup comparisons, while independent samples t tests were used for two-sample comparisons.Results:From IP/LCMS, we identified spleen tyrosine kinase (SYK) as a crucial candidate of TOSO-interacting protein and confirmed it by co-immunoprecipitation. After stimulation with anti-IgM, TOSO over-expression increased the phosphorylation of SYK, and subsequently activated the BCR signaling pathway, which could be reversed by a SYK inhibitor. TOSO knockdown in primary CLL cells resulted in reduced SYK phosphorylation as well as attenuated BCR signaling pathway. The apoptosis rates of the Granta-519 and Z138 cells expressing TOSO were (8.46 ± 2.90)% and (4.20 ± 1.21)%, respectively, significantly lower than the rates of the control groups, which were (25.20 ± 4.60)% and (19.72 ± 1.10)%, respectively (P < 0.05 for both). The apoptosis rate was reduced after knocking down TOSO in the primary CLL cells. In addition, we also found that TOSO down-regulation in primary cells from CLL patients led to decreased expression of BCL-2 as well as lower apoptosis, and vice versa in the cell line.Conclusions:TOSO might be involved in the pathogenesis of CLL by interacting with SYK, enhancing the BCR signaling pathway, and inducing apoptosis resistance.

  • 标签: Chronic lymphocytic leukemia TOSO B-cell receptor signaling pathway SYK Apoptosis
  • 简介:AbstractObjective:This study was performed to investigate the effects of honokiol on the activation of transient receptor potential channel V1 (TRPV1) and the secretion of thymic stromal lymphopoietin (TSLP) in a human benign epidermal keratinocyte line (HaCaT).Methods:HaCaT keratinocytes were cultivated and divided into six groups: capsaicin-induced model control group, capsazepine control group, solvent control group, and three honokiol treatment groups (7.81, 15.63, and 31.25 mg/L of honokiol). The effect of honokiol on calcium (Ca2+) influx was measured by a Ca2+ fluorescence imaging system. The fluorescence intensity (F) of cells was measured. The rate of change in F (ΔF/F0) was calculated, and the ΔF/F0-time curve was constructed. HaCaT keratinocytes were stimulated with polyinosinic:polycytidylic acid, recombinant human tumor necrosis factor α, and recombinant human interleukin 4. Different concentrations of honokiol (15.63, 7.81, and 3.91 mg/L) were added to the cells in the respective honokiol groups; 20 mg/L of dexamethasone or 0.5% dimethyl sulfoxide was added to the cells in the positive control group or solvent control group. The TSLP concentration in the HaCaT keratinocytes of each group was detected by enzyme-linked immunosorbent assay. Statistical analysis was performed by one-way analysis of variance and Dunnett t test.Results:The capsaicin-induced Ca2+ fluorescence intensity in HaCaT keratinocytes was significantly inhibited in the 31.25 mg/L honokiol group; ΔF/F0 at 45 second was 0.76 in the model control group and 0 in the 31.25 mg/L honokiol group. The TSLP level in the 15.63 and 7.81 mg/L honokiol groups was lower than that in the solvent control group (t= 7.382, P= 0.003, and t= 2.766, P= 0.023, respectively), while the TSLP level in the 3.91 mg/L honokiol group was not significantly different from that in the solvent control group (t= 1.872, P= 0.124).Conclusions:Honokiol inhibited the Ca2+ influx induced by capsaicin (TRPV1 agonist) in HaCaT keratinocytes. Honokiol has an inhibitory effect on TSLP secretion in HaCaT keratinocytes.

  • 标签: honokiol keratinocytes transient receptor potential channel V1 thymic stromal lymphopoietin
  • 简介:AbstractBackground:Pancreatic stellate cells (PSCs) activation plays a critical role in the development of chronic pancreatitis. Previous studies confirmed that thromboxane A2 receptor (TxA2r) was overexpressed in activated PSCs in rats. The purpose of this study was to investigate the role of TxA2r in the activation of PSCs induced by 8-epi-prostaglandin F2α (8-epi-PGF2α).Methods:TxA2r expression in both quiescent and activated PSCs was detected by immunocytochemistry and immunoblot assay. Isolated PSCs were treated with 8-epi-PGF2α (10-6, 10-7, 10-8 mol/L) for 48 h, and SQ29548 (10-4, 10-6, and 10-7 mol/L), a TxA2r-specific antagonist, for 48 h, respectively, to identify the drug concentration with the best biological effect and the least cytotoxicity. Then isolated PSCs were treated with SQ29548 (10-4 mol/L) for 2 h, followed by 10-7 mol/L 8-epi-PGF2α for 48 h. Real-time polymerase chain reaction was performed to detect the messenger RNA (mRNA) levels of α-smooth muscle actin (α-SMA) and collagen I. Comparisons between the groups were performed using Student’s t test.Results:TxA2r was up-regulated in activated PSCs in vitro compared with quiescent PSCs (all P < 0.001). Compared with the control group, different concentrations of 8-epi-PGF2a significantly increased mRNA levels of α-SMA (10-6 mol/L: 2.23 ± 0.18 vs. 1.00 ± 0.07, t= 10.70, P < 0.001; 10-7 mol/L: 2.91 ± 0.29 vs. 1.01 ± 0.08, t= 10.83, P <0.001; 10-8 mol/L, 1.67 ± 0.07 vs. 1.00 ± 0.08, t= 11.40, P < 0.001) and collagen I (10-6 mol/L: 2.68 ± 0.09 vs. 1.00 ± 0.07, t = 24.94, P < 0.001; 10-7 mol/L: 2.12 ± 0.29 vs. 1.01 ± 0.12, t = 6.08, P < 0.001; 10-8 mol/L: 1.46 ± 0.15 vs. 1.00 ± 0.05, t = 4.93, P = 0.008). However, different concentrations of SQ29548 all significantly reduced the expression of collagen I (10-4 mol/L: 0.55 ± 0.07 vs. 1.00 ± 0.07, t = 10.47, P < 0.001; 10-6 mol/L: 0.56 ± 0.10 vs. 1.00 ± 0.07, t = 6.185, P < 0.001; 10-7 mol/L: 0.27 ± 0.04 vs. 1.00 ± 0.07, t= 15.41, P < 0.001) and α-SMA (10-4 mol/L: 0.06 ± 0.01 vs. 1.00 ± 0.11, t= 15.17, P < 0.001; 10-6 mol/L: 0.28 ± 0.03 vs. 1.00 ± 0.11, t= 11.29, P < 0.001; 10-7 mol/L: 0.14 ± 0.04 vs. 1.00 ± 0.11, t= 12.86, P < 0.001). After being treated with SQ29548 (10-4 mol/L) and then 8-epi-PGF2α (10-7 mol/L), the mRNA levels of a-SMA (0.20 ± 0.08 vs. 1.00 ± 0.00, t= 17.46, P < 0.001) and collagen I (0.69 ± 0.13 vs. 1.00 ± 0.00, t = 4.20, P = 0.014) in PSCs were significantly lower than those of the control group.Conclusions:The results show that 8-epi-PGF2α promoted PSCs activation, while SQ29548 inhibited PSCs activation induced by 8-epi-PGF2α. The result indicated that TxA2r plays an important role during PSC activation and collagen synthesis induced by 8-epi-PGF2αin vitro. This receptor may provide a potential target for more effective antioxidant therapy for pancreatic fibrosis.

  • 标签: Pancreatic stellate cells Thromboxane A2 receptor 8-epi-prostaglandin F2α SQ29548
  • 简介:AbstractBackground:Natural killer (NK) cells play a critical role in suppressing human immunodeficiency virus-1 (HIV-1) infection, but knowledge on whether and how NK cells affect immune reconstitution in HIV-1-infected individuals who receive antiretroviral therapy (ART) is limited.Methods:We performed a case-control study with 35 healthy individuals and 66 HIV-1-infected patients including 32 immunological non-responders (INRs) with poor CD4+ T-cell recovery (<500 cells/μL after 4 years of ART) and 34 immunological responders (IRs) with improved CD4+ T-cell recovery (>500 cells/μL after 4 years of ART). NK cell phenotype, receptor repertoire, and early activation in INRs and IRs were investigated by flow cytometry.Results:A significantly higher proportion of CD56dimCD16dim/- NK cells was observed in INRs than IRs before ART and after 4 years of ART. The number of CD56dimCD16dim/- NK cells was inversely correlated with CD4+ T-cell counts in INRs before ART (r = -0.344, P = 0.050). The more CD69-expressing NK cells there were, the lower the CD4+ T-cell counts and ΔCD4, and these correlations were observed in INRs after ART (r = -0.416, P = 0.019; r = -0.509, P = 0.003, respectively). Additionally, CD69-expressing CD56dimCD16dim/- NK cells were more abundant in INRs than those in IRs (P = 0.018) after ART, both of which had an inverse association trend towards significance with CD4+ T-cell counts. The expression of the activating receptors NKG2C, NKG2D, and NKp46 on CD56dimCD16dim/- NK cell subsets were higher in IRs than that in INRs after 4 years of ART (all P < 0.01). Strong inverse correlations were observed between CD69 expression and NKG2C, NKG2A-NKG2C+, NKG2D, and NKp46 expression on CD56dimCD16dim/- NK cells in INRs after ART (NKG2C: r = -0.491, P = 0.004; NKG2A-NKG2C+: r = -0.434, P = 0.013; NKG2D: r = -0.405, P = 0.021; NKp46: r = -0.457, P = 0.008, respectively).Conclusions:INRs had a larger number of CD56dimCD16dim/ - NK cells characterized by higher activation levels than did IRs after ART. The increase in the CD56dimCD16dim/- NK cell subset may play an adverse role in immune reconstitution. Further functional studies of CD56dimCD16dim/- NK cells in INRs are urgently needed to inform targeted interventions to optimize immune recovery.

  • 标签: HIV-1 infection Immunological non-responders Natural killer cells Immune reconstitution
  • 简介:AbstractObjective:To investigate whether peroxisome proliferator-activated receptor γ (PPARγ) agonists, rosiglitazone and GW1929, activate the phosphatidylinositol 3-kinase (PI3K)-AKT/protein kinase B pathway and the mitogen-activated protein kinase (MAPK) /extracellular signal-regulated kinase1/2 (ERK1/2) pathway by upgrading the expression of chemerin.Methods:The HTR-8/SVneo trophoblastic cells were cultured in vitro in high glucose concentration (25 mmol/L) to mimic gestational diabetic phenotypes. We transfected small interfering RNA into HTR-8/SVneo cells to silence two receptors of chemerin, that are chemokine-like receptor 1 (CMKLR1) and G protein-coupled receptor1 (GPR1). And recombinant human chemerin, PPARγ agonists (rosiglitazone, 10 μmol/L and GW1929, 10 μmol/L) and PPARγ inhibitor (GW9662, 5 μmol/L) were additionally added to the medium, respectively. The existence of chemerin was verified by immunocytochemistry, and the expressions of PPARγ, chemerin, and its receptors as well as insulin signaling-related factors PI3K, AKT2, and MAPK (ERK1/2) were detected by real time quantitative-polymerase chain reaction and western blot.Results:Chemerin existed in the HTR-8/SVneo cells. Effects of chemerin on PI3K-AKT pathway and MAPK (ERK1/2) pathway were dependent on the density of chemerin. When rosiglitazone and GW1929 were added to the medium, the mRNA levels of PI3K, AKT2, and MAPK1 were upregulated (P < 0.05). Conversely, GW9662 downregulated the mRNA levels of AKT2 and MAPK1 (P < 0.05). Rosiglitazone and GW1929 increased the protein levels of PPARγ, chemerin, CMKLR1 and GPR1 (P < 0.05). Rosiglitazone and GW1929 had no effect on the expression of PI3K p110β and phospho-AKT2 without CMKLR1 (P > 0.05). Meanwhile, the expression of phospho-ERK2 remained unaffected in the absence of GPR1 (P > 0.05).Conclusion:Both rosiglitazone and GW1929 have the effect of improving insulin signaling pathways via upgrading the level of chemerin in high glucose treated HTR-8/SVneo cells.

  • 标签: Glucose Chemerin Chemokine-like receptor 1 G protein-coupled receptor 1 GW1929 Phosphatidylinositol 3-kinase PPAR gamma Protein kinase B beta p42 MAPK Rosiglitazone