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Objective To explore the antitumor small molecules targeting the ubiquitin–proteasome system (UPS) on the basis of active molecules from traditional Chinese medicine. Methods UbG76V-GFP stably expressing cell line was constructed to screen novel small molecule inhibitors targeting UPS. The fluorogenic substrates of Suc-LLVY-AMC, Z-LLE-AMC, and Boc-LRR-AMC were used to assess the effect of dioscin on the 20S proteasome hydrolase activity. The Ub-AMC substrate was used to evaluate the effect of dioscin on the intracellular deubiquitinating enzyme activity. Western blot was used to detect the effect of dioscin on intracellular ubiquitination levels. CCK-8 and colony formation assays were used to detect the inhibitory effect of dioscin on the tumor cell proliferation. Results Dioscin is a UPS inhibitor discovered through the UbG76V-GFP reporter system. It enhances intracellular ubiquitination and inhibits tumor cell proliferation and colony formation by targeting deubiquitinating enzymes. Conclusion Dioscin could significantly inhibit tumor cell proliferation by targeting ubiquitin–proteasome.
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Objective To investigate the change of circulating follicular helper T cells (cTfh) in patients with anti-neutrophil cytoplasmic myeloperoxidase antibody-associated vasculitis (MPO-AAV), and to analyze the relationship between cTfh and disease activity. Methods Thirty-eight untreated MPO-AAV patients (patient group) and thirty-eight healthy volunteers (control group) were enrolled in this study. cTfh and membrane expression of inducible co-stimulator(ICOS)and programmed cell death protein 1(PD-1) were detected by flow cytometry (FCM). Serum anti-neutrophil cytoplasmic myeloperoxidase antibody (MPO-ANCA) was measured by ELISA. Disease activity was evaluated by Birmingham vasculitis activity score (BVAS). Results Compared with those in control group, the proportions of cTfh, ICOS+Tfh and PD-1+Tfh cells in patient group were significantly higher [(25.9±3.8)％vs. (21.0±5.3)％, P<0.001;(1.8±0.8)％vs. (0.8±0.5)％, P<0.001 and (10.2±2.8)％vs. (8.2±2.2)％, P=0.001, respectively]. Meanwhile, the expression of ICOS and PD-1 on cTfh in patient group was markedly more intensive (59.6±10.0 vs.49.2±6.9, P<0.001 and 532.6±104.2 vs. 485.1±73.4, P=0.025, respectively). In patient group, the proportion of cTfh was positively correlated with the ratio of ICOS+Tfh, the expression of ICOS, the level of MPO-ANCA and BVAS (r=0.407, P=0.011; r=0.705, P<0.001; r=0.737, P<0.001 and r=0.663, P<0.001, respectively). The expression intensity of ICOS on cTfh was positively associated with ICOS+Tfh ratio, serum MPO-ANCA and BVAS (r=0.388, P=0.016; r=0.645, P<0.001 and r=0.653, P<0.001, respectively). Nevertheless, the expression of PD-1 on cTfh was only positively correlated with the ratio of PD-1+Tfh (r=0.473, P=0.003). Conclusions Enhanced cTfh in patients with MPO-AAV might produce MPO-ANCA, which is related to the aggravation of MPO-AAV. Thus, cTfh and its ICOS could be potentially targeted for the treatment of MPO-AAV.
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Objective To investigate the expression of CD55 and myeloperoxidase (MPO) on neutrophils in patients with MPO-specific anti-neutrophil cytoplasmic antibody associated vasculitis(MPO-AAV), and analyze the relationship between the expression and clinical manifestation.Methods Forty untreated patients with active MPO-AAV (patient group) and 30 healthy volunteers (control group) were enrolled in this study.The CD55 on neutrophils and both membrane and cytoplasmic MPO were detected by flow cytometry.Serum fragment-from the activated complement factor B(Ba) and MPO were measured by ELISA.The clinical activity of vasculitis was valued by Birmingham vasculitis activity score-version 3(BVAS-V3).The significance of laboratory data was evaluated by Spearman correlation test and multivariate linear regression analysis.Results (1)The mean fluorescence intensity(MFI) of CD55 expressed on neutrophils was significantly higher than that in control group[4 068.6±2 306.0 vs 2 999.5±1 504.9,P=0.033].Similar results of serum MPO and Ba in patient group were found compared to controls [500.0(381.0, 612.7) IU/L vs 286.9(225.5, 329.1) IU/L,P<0.001;35.2(25.2, 79.5) ng/L vs 18.0(15.0, 28.0) ng/L,P<0.001], respectively.However, MIF of cytoplasmic MPO in patients was significantly lower than that of control group(1 577.1±1 175.9 vs 3 105.3±2 323.0,P=0.003).(2) In patient group, cytoplasmic intensity of MPO was negatively associated with the serum levels of MPO(r=-0.710,P<0.001) and Ba (r=-0.589,P=0.001).Moreover, serum MPO was positively associated with serum Ba(r=0.691,P<0.001).Membrane intensity of CD55 on neutrophils was positively correlated with patient age (r=0.514, P=0.001), C reactive protein (r=0.376, P=0.018), peripheral neutrophils count (r=0.485, P=0.001) and BVAS-V3 (r=0.484, P=0.002), whereas negative correlation between membrane CD55 and disease duration was seen (r=-0.403,P=0.01).(3) The result of multiple linear regression analysis showed there was statistically significant positive correlation between MFI of CD55 expressed on neutrophils and BVAS-V3 (β=0.001,P=0.027).Conclusions In MPO-AAV,CD55 expression on neutrophils is markedly enhanced, which is one of the independent risk factors related to disease activity.It might protect neutrophils from attacking AAV, CD55 expression on neutrophils is markedly enhanced, which is one of the independent risk factors related to disease activity.It might protect neutrophils from attacking by complement alternative pathway.Activated neutrophils release more MPO and lysosome to intensify the inflammation reaction and aggravate the disease.Thus CD55 might become a new potential target for the treatment of this disease in the future.
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Objective To explore preliminarily the role of the E2 subunit of pymvate dehydrogenase (PDC-E2) modified by xenobiotics (e.g.2-octynic acid,2-OA) in the pathogenesis of primary biliary cirrhosis (PBC).Methods Patients of PBC (102 cases),primary sclerosing cholangitis (PSC,34 cases) and healthy controls (HC,50 cases) were selected.The anti-PDC-E2,anti-2-OA and anti-lipoic acid (LA) antibody in the peripheral blood of the 3 groups were tested by enzyme linked immunosorbent assay (ELISA).By inhibitive ELISA (iELISA),30 of the 102 PBC patients with anti-PDC-E2 antibody but without anti-2-OA antibody were selected to detect whether there was any new epitope on the PEC-E2 conjugated with 2-OA.The chi-square test and Fisher exact test were taken to analyze the enumeration data.The two-tailed unpaired t test with Welch's correction was used to compare the measurement data.Spearman rank correlation analysis was also employed for proper test.Results The positive rate of anti-PDC-E2,anti-LA and anti-2-OA antibody in PBC patients was 94.1％(96/102),73.5％(73/102) and 53.9％(55/102) respectively,all of which were statistically significantly higher than those in healthy controls group but were of no significant difference between PSC and healthy controls group.There was no significant relevance between the levels of Anti-LA and anti-2-OA antibody in the PBC group (r=-0.065,P=0.520).The iELISA results showed that the antibody,which only identified the epitopes on 2-OA-PDC-E2 induced by the 2-OA conjugation with PDC-E2,existed in 40％(12/30) of the PBC patients,and more interestingly,this antibody was predominantly appeared in PBC patients at their early clinical stage.Conclusion There are anti-LA antibody and anti-2-OA antibody in PBC patients,which have shown no significant association with each other.It is very likely that new antigenic conformational epitopes on PDC-E2 modified by 2-OA would emerge,which might led to the immune response in the individuals who are susceptible to PBC,and thus contribute for the breaking of PDC-E2 immune tolerance,and PBC occurrence finally.
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The aim of this study is to investigate the critical factor affecting the properties of PLGA microspheres fabricated by a solid-in-oil-in-water (S/O/W) emulsion technique with BSA as a model protein. Prior to encapsulation, the BSA microparticles were fabricated by a modified freezing-induced phase separation method. The microparticles were subsequently encapsulated into PLGA microspheres by S/O/W emulsion method, then Motic BA200 biological microscope, confocal laser scanning microscope, scanning electron microscope were used to observe the structure of S/O/W emulsion and PLGA microspheres. The protein content extracted or released from BSA microspheres was measured by Bradford protein assay method. It was found that NaCl added in the outer aqueous phase effectively suppressed material exchange between the inner and outer phase of S/O/W emulsion. Then, the structure and permeability of obtained microspheres were influenced. As a result, with the increase of NaCl concentration in the outer aqueous phase, the encapsulation efficiency of microspheres significantly increased from 60% to more than 85%, the burst release of microspheres reduced from 70% to 20%, and the particle size decreased from 103 microm to 62 microm. Furthermore, the rehydration of encapsulated protein was also retarded and then integrity of BSA was successfully protected during encapsulation process. In vitro release test showed that BSA released from PLGA microspheres in a sustained manner for more than 30 days.