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Objective To prepare a mouse anti-human B7-2 monoclonal antibody ( McAb) and to study its effect on the induction of death-related molecules on the surface of tumor cells. -ethods Trans-genic cells, L929-B7-2, were used as the immunogen to immunize BALB/c mice. Through cell fusion, mul-tiple screening by immunofluorescence labeling and continuous subcloning, the hybridoma secreting B7-2 McAb was obtained. Biological characteristics of the McAb were analyzed using Ig subclass identification test strip, antigenic site competition inhibition assay and specific cell membrane molecules binding test. McAb was prepared through inducing ascites in vivo and then purified by protein G affinity chromatography. The purified McAb was co-cultured with 8266 cells, naturally expressing B7-2 molecules, to observe the expres-sion of Fas and FasL on cell surface by flow cytometry ( FCM) . Results The prepared B7-2 McAb labeled as 12G4 was successfully obtained with a titer of 0. 1 μg/5×105 cells. Its heavy and light chains were IgG2b and κ, respectively. The concentration of the purified ascites-derived antibody was 1. 61 mg/ml. FCM re-sults showed that the 12G4 McAb recognized cell membrane molecules well with a positive binding rate of 89. 6％ to 8266 cells. The mean value of the Fas molecule on the cell surface increased after incubating with 20 μg/ml of 12G4 McAb for 12 h and reached the peak of 62575. 8 at 48 h, which was significantly higher than the maximum value of 57135. 4 in the IgG control group (P<0. 05). After culturing the cells with 20μg/ml of 12G4 McAb for 12 h, the expression of FasL on the cell surface also increased and reached the maximum of 7. 98％ at 48 h, which was significantly higher than the 1. 10％ in the IgG control group ( P<0. 05). Conclusions B7-2 McAb was successfully prepared. It could be used to induce the expression of some death-related molecules on the surface of tumor cells.
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Objective To evaluate the protective effect of epigallocatechin gallate (EGCG) on lipopolysaccharide (LPS) -induced acute kidney injury (AKI) in rats and its underlying mechanisms. Methods Sprague-Dawley rats were randomly divided into the Sham group, AKI group, EGCG group and TLR4 group (n = 10 each). To establish the rat model of endotoxemia, serum creatinine (Cr) and urea nitrogen (BUN) levels were detected by biochemical assays; serum interlukin (IL) -6, IL-1β, IL-10, and TNF-α levels were detected by ELISA; kidney histopathology was examined by hematoxylin and eosin (HE) staining method; and expression of TLR4, Myd88 and nuclear factor-kappa B (NF-κB) in rat kidneys at both protein and mRNA levels was detected by Western blotting and qRT-PCR, respectively.Results Kidney injury increased significantly in AKI group compared to the sham group. Serum Cr, BUN, IL-6, IL-1β, and TNF-α levels significantly increased whereas IL-10 levels significantly decreased in AKI group compared to the sham group. Expression levels of TLR4, Myd88, and NF-κB also significantly increased at both protein and mRNA levels in AKI group compared to the sham group. Treatment with EGCG prior to induction of LPS-mediated AKI conferred protection against AKI by significantly reducing the expression of inflammatory markers such as, TLR4, Myd88, and NF-κB. Given TLR4 inhibitor based on this, the protective effect of EGCG on AKI was via inhibition of the TLR4/Myd88/NF-κB pathway. Conclusion EGCG exhibited a protective effect against LPS-induced AKI by inhibiting the activation of TLR4/Myd88/NF-κB pathway.
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Objective To study the therapeutic effect of anti-CD80 bivalent antibody on mouse lu-pus nephritis and to explore the possible molecular mechanism. Methods A mouse model of lupus nephritis was established through intraperitoneal injection of 0. 5 ml of pristine in female C57BL/6J mice. Appearance of urinary protein and significantly increased levels of peripheral antinuclear antibody ( ANA) and anti-doub-le-stranded DNA ( anti-dsDNA) antibody in the fourth month after injection indicated that the mouse model was established successfully. Then the mice were divided into two groups including anti-CD80 bivalent anti-body intervention group (injected with 200μg of anti-CD80 bivalent antibody at day 1, 3, 5, 8 and 15, fol-lowed by three times of injection with an interval of one month) and model group ( injected with the same protein using the same strategy). A normal control group was set up accordingly. Albustix test paper was used to monitor the dynamic changes in mouse urinary protein. Flow cytometry was used to analyze the acti-vation of immune-related cells in spleen. Levels of autoantibodies ( ANA and anti-dsDNA) and levels of IFN-γ and IL-4 in serum were detected by indirect immunofluorescence assay. Renal tissue samples were an-alyzed with hematoxylin and eosin ( HE) staining and immunocomplex ( IC) assay. Results Urinary pro-tein level of the anti-CD80 bivalent antibody intervention group was significantly lower than that of the model group (P<0. 05). Activated macrophages, dendritic cells, neutrophils and B cells in spleen tissues of the anti-CD80 bivalent antibody intervention group were significantly less than those of the model group ( P<0. 05), and the numbers of CD4+ and CD154+ T cells were significantly less than those of the model group (P<0. 05). Positive rates and titers of ANA and dsDNA in serum samples of the intervention group were lower than those of the model group (P<0. 05). Levels of IFN-γand IL-4 in serum samples of the interven-tion group were decreased as compared with those of the model group (P<0. 05). HE staining and immuno-fluorescence assay showed that glomerular inflammatory injury and necrosis were alleviated and kidney im-mune complex deposition was reduced after anti-CD80 bivalent antibody intervention. Conclusion Anti-CD80 bivalent antibody specifically binds to the CD80 molecule on antigen presenting cell surface, blocks the CD80/CD28 co-stimulatory signaling pathway and down-regulates the body′s immune response, which al-leviates and reverses the lupus-like nephritis-induced pathological damages in mice.
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Objective To study the therapeutic effect of anti-CD80 bivalent antibody on mouse lu-pus nephritis and to explore the possible molecular mechanism. Methods A mouse model of lupus nephritis was established through intraperitoneal injection of 0. 5 ml of pristine in female C57BL/6J mice. Appearance of urinary protein and significantly increased levels of peripheral antinuclear antibody ( ANA) and anti-doub-le-stranded DNA ( anti-dsDNA) antibody in the fourth month after injection indicated that the mouse model was established successfully. Then the mice were divided into two groups including anti-CD80 bivalent anti-body intervention group (injected with 200μg of anti-CD80 bivalent antibody at day 1, 3, 5, 8 and 15, fol-lowed by three times of injection with an interval of one month) and model group ( injected with the same protein using the same strategy). A normal control group was set up accordingly. Albustix test paper was used to monitor the dynamic changes in mouse urinary protein. Flow cytometry was used to analyze the acti-vation of immune-related cells in spleen. Levels of autoantibodies ( ANA and anti-dsDNA) and levels of IFN-γ and IL-4 in serum were detected by indirect immunofluorescence assay. Renal tissue samples were an-alyzed with hematoxylin and eosin ( HE) staining and immunocomplex ( IC) assay. Results Urinary pro-tein level of the anti-CD80 bivalent antibody intervention group was significantly lower than that of the model group (P<0. 05). Activated macrophages, dendritic cells, neutrophils and B cells in spleen tissues of the anti-CD80 bivalent antibody intervention group were significantly less than those of the model group ( P<0. 05), and the numbers of CD4+ and CD154+ T cells were significantly less than those of the model group (P<0. 05). Positive rates and titers of ANA and dsDNA in serum samples of the intervention group were lower than those of the model group (P<0. 05). Levels of IFN-γand IL-4 in serum samples of the interven-tion group were decreased as compared with those of the model group (P<0. 05). HE staining and immuno-fluorescence assay showed that glomerular inflammatory injury and necrosis were alleviated and kidney im-mune complex deposition was reduced after anti-CD80 bivalent antibody intervention. Conclusion Anti-CD80 bivalent antibody specifically binds to the CD80 molecule on antigen presenting cell surface, blocks the CD80/CD28 co-stimulatory signaling pathway and down-regulates the body′s immune response, which al-leviates and reverses the lupus-like nephritis-induced pathological damages in mice.
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Objective:To construct lentiviral vector specific for mouse B7-1 RNA interference and study lentivirus-mediated B7-1 gene silencing effects in L929 fibroblast cells.Methods:Three candidate sequences for B7-1 RNAi selected from coding sequence of mouse B7-1 transcription were used to design short hairpin RNA ( shRNA ) templates and then cloned into lentiviral expression plasmid followed with correctness identification of inserted sequence by DNA sequencing.Recombinant lentivirus were prepared by co-transfecting lentiviral expression vector and packaging plasmids into 293T cells.Then the resulting culture supernatant containing infectious lentiviral particles was pooled and centrifuged via ultra-centrifugation.Infectious titer of the preparations was determined by detecting the expression of GFP in 293T cells after transfected by lentivirus.Cultured L929 cells were transfected with lentivirus to deter-mine transduction efficiency and silencing efficacy of B7-1 expression by flow cytometry.Transducted L929 cells were then screened using puromycin to generate stable cell clones followed by flow cytometry analysis of GFP and B7-1 expression.A mixed reaction system consisting of stable B7-1 silencing L929 cells and mouse splenic T cells was used to analyze ability of the established cell line to trigger T cells proliferation.Results: Lentiviral expression vector for mouse B7-1 RNAi was correctly constructed with inserted sequences as designed.Recombinant RNAi lentivirus were prepared with titers ranging (3-5) ×108 TU/ml and efficacy to mediate GFP transgene expression and B7-1 silencing.B7-1 expression and the ability to trigger T cells proliferation of stable L929 cells were suppressed significantly ( P<0.05 ).Conclusion: We generated lentiviral vector specific for mouse B7-1 RNAi with high performance of transduction efficiency as well as B7-1 silencing efficacy and the recombinant RNAi lentivirus can mediated stable B7-1 gene silencing in L929 cells and inhibition of T cells proliferation induced by B7-1/CD28 co-stimulatory signal.
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Objective:To establish a pristine-induced rheumatoid arthritis model in mice,and to evaluate its histological and immunological distinction.Methods:Thirty female BALB/c mice,6-8 weeks old,were randomly divided into 2 groups,a control group and pristine group.The mice in pristine group were injected intraperitoneally with 0.5 ml pristine three times at 0,9,and 18 weeks, while mice in the control group receiving saline at the same time.Arthritis score and paw thickness were measured and histopathological assessment of joint sections was performed.The expression of phagocytes,dendritic,neutrophils,T and B cells markers in spleen were determined by flow cytometry.Results:In model-marking group,11 mice were presented with macroscopic evidence of arthritis such as erythema or swelling.The paw thickness in pristine-induced mice was significant higher than that in the control groups[(2.90±0.51) mm vs(1.29±0.47 mm),P<0.05].In addition,arthritis score in pristine-induced mice was 9.55±2.80 at 21 weeks after first injection with 0.5 ml pristine.H&E staining revealed a significant increase of synovial inflammation, cartilage and bone destruction after stimulated with pristine.Meanwhile,the expression levels of CD11b,CD11c,GR1,CD4,CD8 and CD154 were obviously increased in model-marking group when compared with that in control group.Conclusion: The pristine-induced model presents the similar histological and immunological distinctions with human rheumatism arthritis,which can mimic the pathogenesis of rheumatism arthritis.
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Objective:On the basis of the use of chemical methods to establish mouse model of lupus nephritis and its biological identification , we investigate the reverse effect of pathological lesions of B 7-1 human-mouse chimeric antibody blockade against B7/D28 signaling pathway in mice with lupus nephritis model.Methods:Pristane was injected intraperitoneally to 6-week-old female C57BL/6J mice at dose of 0.5 ml per mouse in one go,and urine protein,ANA and renal pathological changes were detected on a monthly basis.Mice whose urine protein content reached ++and ANA fluorescence intensity reached ++were randomly devided into three groups ,five each.Antibody intervention group was sequentially injected with B 7-1-mouse chimeric antibody by orbital venous , positive control group was injected with immunosuppressant CTX , negative control group was injected with isotype control IgG.Urine protein and ANA were also detected on a monthly basis.Mice were sacrificed three months after intervention was executed.Kidney was used for H&E dying , IC detection and electric microscope observation.Results: After four-month Pristane induction , urine protein content of 80%mice reached +-+++,meanwhile,serum ANA fluorescence intensity reached ++-+++.Glomerulonephritis infiltrating cells were observed Mice with urine protein and ANA , glomerular inflammatory cell infiltration , tubular epithelial cell degeneration visible edema ,vascular congestion significantly ,fibrosis.After antibody intervention ,urine protein content in antibody intervention group gradually reduced from ++-+++to ±-+++,ANA ++-+++to +-++,and were significantly different from that in the negative control group ( P<0.01 ).Analysis of kidney H&E dying showed that antibody glomerular infiltration of inflammatory cells in the intervention group and tubular congestion and other symptoms were improved significantly.Immunofluorescence staining indicated that fluorescence intensity of IC was significantly reduced in the antibody intervention group.Electron dense deposits reduction and glomerular basement membrane uniformity were observed in antibody intervention group by electric microscope when compared with the negative control group.Conclusion:B7-1 antibodies could downregulate immune response through inhibiting B 7-1/CD28 signaling pathway , reducing the production of autoantibodies and reversing pathological damage caused by autoimmune response .
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Objective To study the effect of acute hypervolemic hemodilution on expression of plasma bac-tericidaL/permeability-increasing protein (BPI) in patients undergoing total hip replacement. Methods Twenty ASA Ⅰ-Ⅱ patients undergoing elective total hip replacement were randomly divided into two groups (n=10 for thesia. The blood loss,blood transfusion and the time of operation were recorded. Venous blood samples were taken before anesthesia (T0) ,at the begining of operation (T1) ,30 min after operation (T2) ,and at the end of operation (T3) for determination of plasma bactericidal/permeability-increasing protein. Results The blood loss and the blood transfusion in HES group were significantly lower than that of LR group[blood loss: (560±90)ml vs (810±110) ml and blood transfusion: (200±100) ml vs (600±200) ml,t=5.562 and 5.657,P<0.001]. The plasma BPI concentrations in HES group were significantly increased at T2～T3 as compared to baseline value at T0 [(8.9±1.6)μg/L,(13.4±1.2)μg/L and (4.9±1.2)μg/L,P<0.05]. The plasma BPI concentrations in LR group were significantly increased at T2～T3 as compared to baseline value at T0 [(7.3±1.2)μg/L,(9.9±0.8) μg/L and (5.0±1.1)μg/L,P<0.05],but were lower than those in HES group (t=2.530 and 7.674,P=0.021 and 0.001 ). Conclusion Acute hypervolemic hemodilution with 200/0.5 hydroxyethyl starch can reduce blood transfusion during total hip replacement operation and also can increase the BPI level which would beneficial for the immunological function.
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Objective To establish the sensitive,specific,stable and convenient immunoradio assay for detecting human soluble IL-6R?.Methods The hybridoma cell lines were obtained by fusing spleen cells of BALB/c mice that had been immunized with soluble IL-6R? protein to mouse myeloma cells sp2/0. Ascites were used to produce the monoclonal antibodies (mAbs). The mAbs were purified by protein G immunoaffinity method. The mAb SI10 was used as coating antibody, the other mAb H126 recognized different epitope from SI10 was labeled by 125I. Results The immunoradio assay for detecting soluble IL-6R? was set up. It has high stability and accuracy. The detecting limit is 10 ng/ml. The serum concentration of soluble IL-6R? is (81.96 ? 7.23) ng/ml in healthy donors and (237.58?70.96) ng/ml in patients with multiple myeloma. Significant difference was founded between two groups (P
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Objective To investigate the levels of IL-2,IL-6and their receptors in patients with systemic lupus erythematosus(SLE)before and after treatment.Methods The levels of IL-2,IL-6and their receptors were detected by ELISA,immunofluorescence labelling technique and flow cytometry analysis,respectively,in peripheral blood taken from SLE patients before and after treatment and normal controls.Results①IL-2was significantly decreased(P
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Aim To prepare the monoclonal antibodies (mAbs) against human CD28 and to study its biological feature. Methods The hybridoma cell lines were obtained by fusing spleen cells of Blab/c mice that had been immunized with murine lymphoma cells transfected with full-length huaman CD28 cDNA to myeloma cells Sp2/0. Ascites were induced to produce the mAbs. The specificity and affinity of the mAb 18G8 was verified by CD28 competitive inhibitory test and FACS. Reactivities of mAb 18G8 to PBTC, U266, 8226, Jurkat and Daudi cell were studied by indirect immunofluorescence staining. mAb 18G8-inducing proliferation of peripheral blood T cells (PBTCs) was determined by [3H]thymidine incorporation test. Results Five hybridoma cell lines were obtained. mAb 18G8 secreted by one of the them, belong to mouse IgG2a. It recognized a epitope different from which recognized by the standard mAb(clone CD28.2). The Reactivitrates of the mAb 18G8 to PBTC, U266, 8266, Jurkat and Daudi cells were 70.2％ , 99.3％ , 98.6％ , 76.4％ and 1.9％ , respectively, similar with CD28.2. It was indicated that different antigen epitopes expressed on all above cells. mAb 18G8 could promote the PBTC proliferation in vitro(SI=7). It was indicated that The substitution of mAb 18G8 for B7-1 molecule could also mediate the costimulatory signals. Conclusion 18G8 is a specific and functional anti-CD28 mAb it may be of significant value in basic studies and clinical application.
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Objective:To obtain a monoclonal antibody(mAb) against human CD80(B7 1) and to study of its biological effects.Methods:The hybridoma cell line was obtained by using the B lymphoma hybridoma technique after immunization of Balb/c mice with XG7 B7 the cells.Ascites were induced to produce the mAb.The specificity and affinity of mAb were verified B7 competition and FACS.Expression of B7 1 in PBLs,DCs,Raji and Daudi were studied by indirect immunofluorescence.Using counting and trypan blue staining,inhibitory effects of mAb on Raji and Daudi cells were analyzed.The neutralization activity of the 4E5 determined by MTT assay using PBLs as response cells.Results:The anti CD80(B7 1) was obtained.The expression of B7 1 in PBLs、DC、Raji ad Daudi was 10 2%,95 1%,96 7% and 89 2%,respectived 4E5 can inhibit the growth in Raji and Daudi cells and block the costimulatory signals of B7/CD28.Conclusion:4E5 is a specific and functional anti CD80(B7 1) and has high affinity for its ligand.It may be of significant value in basic studies and find clinical applications.
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Objective:To prepare the monoclonal antibody(mAb) against human B7 1 and analyse its biological characteristics.Methods:The B lymphocytes hybridization technique was applied by using XG7 B7 cell,a multiple myeloma(MM) cell line transfected with human B7 1 gene,as immunogen;the specificity and the antigen binding activity of mAbs were identified by flow cytometry and Western blot analysis;its biological effects on human PBTC and human B lymphoma cell line were examined by 3H TdR incroporation and annexin V satining.Results:Four mouse anti human B7 1(B7 1) hybridoma(1F11,3H8,6H2,7B10) were obtained.They secrete continuosly and steadily specific anti human B7 1(B7 1) mAb and their subclasses belong to IgG1 and IgM respectively;three of four mAbs could inhibit the proliferation of response cells(the human peripheral blood T lymphocytes),stimulated by costimulatory molecule B7 1.Furthermore,it was found that these mAbs induced the apoptosis of human B lymphoma cell line,Raji,which express naturally human B7 1 molecule,by using annexin V staining analysis after 24 hours of mAb treatment.Conclusion:Sucessefully obtained four mouse anti human B7 1 functional monoclonal antibodies,which have a potential value in anti allogenetic graft rejection and in the therapeutic approach of B lymphoma.
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Objective:To prepare mouse anti human CD40L antigen monoclonal antibody and study its biological characteristics and functions.Methods:Using CD40L transfected cell as antigen,cell fusion,mAb screening,immunofluorescence,Western blot and competitive test,obtain two mouse anti human CD40 mAb.Their biological functions are evaluated by the analysis of the effect of the Daudi cell proliferation and the mixed lymphocyte reaction.Results:On the basis of phenotype analysis and competition test,it was evidenced that 1B1 and 4F1 recognized different epitopes of human CD40L antigen specially,and they could reverse the growth inhibition of Daudi cell mediated by CD40L transfected cells and reduce MLR in different extents.Conclusion:Two stable hybridomas murine anti human CD40L monoclonal antibodies have been obtained and antibodies(1B1?4F1)showed a obviously blocking function for CD40/CD40L signal.
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Objective:To establish the sensitive,specific,stable and convenient sgp130 ELISA kit.Methods:The mAb T2 against human gp130 was used as coating antibody;the other mAb T12 recognized different epitope with T2 was labeled by biotin,then a ELISA kit for detecting sgp130 was set up.Results:sgp130 ELISA kit is successfully established and its sensitivity is 10 ng/ml.After the kit is placed in 4℃ for 3 months,the kit's CV is less than ?7.6% and the retrievable rate is 95%～111%.These indicate that it has highly sensitivity,stability and accuracy.The normal serum concentration of sgp130 in healthy donors is 536.92～287.88(ng/ml),but there is higher in patients with hyperthyroidism(937.16?217.5) and chronic nephritis(806.45?138.47).Significant difference is found comparing with normal control(P