1.Humoral and cellular immune responses induced by DNA vaccine based on major outer membrane protein of chlamydia trachomatis
Zhongyu LI ; Yimou WU ; Minjun YU ; Chaoqun CHEN
Immunological Journal 2005;(6):457-459
Objective To construct DNA vaccine containing MOMP gene of Chlamydia trachomatis and to observe immune response in mice. Methods Mice of 4 - 6 weeks old were immunized with pcDNA3.1-MOMP or pcDNA3.1 intramuscularly at a dose of 100 μg. Booster immunizations were employed at 2-week interval for two times. Specific antibody in the sera of mice and the level of IFN-γ in murine spleen lymphocyte supernatant were detected by ELISA. The proliferation response of spleen cells was detected by MTT assay. Results Significant specific antibody titers were observed and the highest titer was 1: 1 024 in mice after three times immunization with pcDNA3.1-MOMP. The proli-feration response of spleen cells were significantly higher than that of mice injected with pc DNA3.1. IFN-γ reached(532.0 + 45.4)pg/mL in immunized mice. Conclusion Strong responses of humoral and cellular immunity can be evoked by DNA vaccine of pcDNA3.1-MOMP in mice.
2.Construction of Helicobacter pylori Lpp20 DNA vaccine and primary study of its immunocompetence in mice
Zhijie LIU ; Yan ZHANG ; Cunyan LI ; Hong QIU ; Minjun YU
Chinese Journal of Microbiology and Immunology 2008;28(11):1035-1039
Objective To construct an eukaryotic expression plasmid PeDNA3.1 (+)/Lpp20 and to detect its expression in HeLa cells, and to observe the humoral and cellular immune responses in C57BL/6 mice induced by the Helicobacter pylori Lpp20 DNA vaccine injected intramuscularly. Methods The Lpp20 gene was amplified by PCR. PCR product was subcloned into the eukaryotic expression vector pcDNA3.1 (+)/ Lpp20, and the recombinant plasmid was transfected into HeLa cells using Liposome. After verifying that the Lpp20 antigen gene could be expressed in HeLa cells. Six weeks old C57BL/6 mice were immunized with pcDNA3.1 (+)/Lpp20 or pcDNA3.1 (+) or PBS buffer intramuscularly at 2-week interval for four times. ELISA was used for the quantitative detection of the specific IgG antibody in the sera of C57BL/6 mice and the cytokine IFN-γ in mice spleen lymphocyte culture medium after stimulating by Lpp20. The proliferation response of spleen cells was detected by MTT assay. The Lpp20 gene in muscle was identified by PCR. Results The significant specific antibody titers were detected by ELISA in DNA vaccine groups and the highest titer was 1:1024 after 6 weeks. The cytnkine IFN-γ in mice inoculated with pcDNA3.1 (+)/Lpp20 was increased and reached (410.36±56.23) pg/ml. A significant difference was tested between the experiment group and the control group[(25.26±10.85)pg/ml] ,P <0.01. The proliferation response of spleen cells of DNA vaccine group(SI: 2.37±0.22) was significantly higher than those of mice injected with pcDNA3.1 (+) (SI:1.53+0.47) ,P<0.01. Lpp20 gene could exist constantly in musculature cells of mice. Conclusion The eukaryotic expression recombinant pcDNA3.1 (+)/Lpp20 was successfully constructed. Strong humoral and cellular im-munity can be induced by DNA vaccine of pcDNA3.1(+)/Lpp20 in C57BL/6 mice, which might be helpful for further investigation concerning the immunoprotection of DNA vaccine.
3.Helicobacter pylori VacA up-regulates secretion of macrophages by activating nuclear factor kB
Cunyan LI ; Yan ZHANG ; Minjun YU ; Zhijie LIU ; Wen YU
Chinese Journal of Microbiology and Immunology 2009;29(5):454-459
Objective To study the effect of VacA on the secretion of THP-1 macrophages as an individual virulence determinant, and the effect of NF-kB on the secretion of THP-1 macrophages. Methods The recombinant plasmid pDsRed-Monomer-Cl/vacA was transfected into macrophages. The cytokine con-tent of TNF-α or IL-1β in the culture medium was tested quantitatively with ELISA kit, respectively. The content of NO or ROS in the culture medium was tested with Griess reagent or DCFH-DA fluorescent probe. The apoptosis rate of macrophages was tested by flow cytometry. The effect of PDTC, an inhibitor of NF-kB, on the secretion and apoptosis of macrophages transfected with the recombinant plasmids, was also studied. The activity of NF-kB was examined in THP-1 cells by electrophoretic mobility gel shift assay(EMSA). Re-suits At 6 h after transfection, the level of TNF-α and IL-1 β in macrophages transfected with the recombi-nant plasmids was significantly higher than that of the control group (P <0.05). At 6 h or 12 h after trans-fection, the level of NO and ROS in macrophages transfected with the recombinant plasmids was significantly higher than that of the control group (P <0.05). At 16 h after transfection, the apoptosis rate of macropha-ges transfected with the recombinant plasmids was significantly higher than that of the control group (P < 0.05). PDTC decreased the production of TNF-α, IL-1 β, NO, ROS and apoptosis rate induced by VacA. VacA was found to trigger NF-kB activation. Conclusion The over-expression of VacA fusion protein can up-regulate secretion and apoptosis of macrophages. Activation of NF-kB is probably involved in the produc-tion of TNF-α, IL-1β, NO, ROS and apoptosis induced by VacA.
4.Expression and Identification of Major Outer Membrane Protein of Chla mydia trachomatis in Escherichia coli
Zhongyu LI ; Yimou WU ; Chaoqun CHEN ; Minjun YU
Chinese Journal of Dermatology 2003;0(12):-
Objective To construct the recombinant plasmid containing the major outer membrane protein(MOMP) gene of Chlamydia trachomatis and expres s MOMP protein in E.coli BL21. Methods The MOMP gene was amplified by polymera se chain reaction from the genome of Chlamydia trachomatis serovar D. The amplif ied fragment was directly inserted into pUCm-T vector and verified by DNA sequen cing. MOMP gene was then subcloned into the prokaryotic expression vector pET-22 b(+). The recombinant protein of MOMP was purified by Ni-NTA affinity chromatogr aphy and identified by SDS-PAGE and Western blot. Results The MOMP gene, which is about 1 200 bp, was successfully amplified and cloned. The DNA sequence of t he cloned MOMP gene was the same as that published by the GenBank. SDS-PAGE anal ysis showed that the relative molecular weight of this fusion protein was about 47 kDa which was consistent with the theoretically predicted value, and the spec ificity of this recombinant protein was confirmed by Western blot. Conclusions The MOMP gene of Chlamydia trachomatis was successfully cloned and expressed in the prokaryotic expression system, which may lay the foundation for the developm ent of Chlamydia trachomatis vaccine.
5.Continuous Axenic Cultivation of Pneumocystis carinii Isolated from the Bronchoalveolar Lavage Fluid of Infected Rat
Minjun HUANG ; Yijun AN ; Shuzhen LI ; Siqi LU ; Zengzhu GUO
Chinese Journal of Parasitology and Parasitic Diseases 1987;0(02):-
Objective To establish axenic cultivation of Pneumocystis carinii (P.c). Methods The organisms of P.c were isolated from the bronchoalveolar lavage fluid (BALF) of the rats with Pneumocystis carinii pneumonia (PCP) and cultured in a medium which was based on IMDM (GIBCO) supplemented with S-adenosyl-L-methionine, putrescine, N-acetyl glucosamine, putrescine, L-cysteine and L-glutamine, and newborn calf serum. The organisms cultured in the system were identified by observing the morphology of cysts in smears stained with Gomori's methenamine silver nitrate stain (GMS). Ultrastructure of the cysts/trophozoites was examined by transmission electron microscopy. The sequences of mitochondria] large ribosomal DNA subunit of the cutured organisms were compared with the Pneumocysti carinii f.sp. ratti variant isolate (GenBank No U20173) and Pneumocystis carinii f.sp.hominis (GenBank No M58605). Results Five isolates of P.carinii received from BALF of 8 rats with PCP were cultured axenically and continuously in the system. The cultured organisms could be stored in frozen condition and used to reinitiate culture, and were amplified by 19-22 times within 72 h. The morphology, ultrastructure and gene sequencing of the cultured organisms confirmed that the isolated organisms were P.carinii. Conclusion Five continuously and axenicly cultured isolates of P.carinii have been received.
6.Significance of preoperative carbohydrate loading and postoperative enteral nutrition in patients with gastric cancer operation
Lianghui LI ; Qi LUO ; Liyu WEI ; Minjun MENG ; Songen ZHANG
Parenteral & Enteral Nutrition 1997;0(03):-
Objective: To explore the clinical significance of combination preoperative carbohydrate loading and postoperative enteral nutrition in patients with gastric cancer during perioperative period. Methods: 70 patients were randomly divided into group A(preoperative fasting + postoperative EN,n = 23),group B(preoperative carbohydrate loading + postoperative TPN,n = 23) and group C(preoperative carbohydrate loading + postoperative EN,n = 20).After operation,insulin sensitivity,nutritional status,immune function and clinical outcome were compared among three groups. Results: Compared with the other two groups in insulin sensitivity,nutritional status,immune function and clinical outcome,the group C was better and different(P
7.Immunocompetence and Immunoprotection of a DNA vaccine NMB0315 against N.meningitidis serogroup B in mice
Kaiming LI ; Meihua XIE ; Minjun YU ; Shuangyang TANG ; Lusi ZHANG ; Suhong DENG ; Sihai HU
Chinese Journal of Immunology 2015;31(12):1648-1653,1658
Objective:To construct NMB0315 eukaryotic expression recombinant vector ,detect specific humoral and cellular immune response induced by the recombint DNA vaccine intramuscularly in female BALB /c mice,evaluate the immunocompetence and immunoprotection of the vaccine , so as to provide experimental basis for the development of a novel nucleic acid vaccine against N.meningitidis serogroup B .Methods: The whole NMB0315 gene was amplified by PCR from the standard strains MC 58 genomic DNA,cloned into a plasmid pcDNA3.1(+),identified by double digestion of the recombinant plasmid with restriction enzymes and se -quencing.The recombinant vector pcDNA 3.1 (+)/NMB0315 was transfected into eukaryotic COS-7 cells and RAW264.7 cells, the NMB0315 protein was detected by immunocytochemical method and Western blot respectively .The levels of specific humoral and cellular immune response were detected after inoculating in female BALB /c mice intramuscularly with the recombinant plasmid .The immune protective effect was investigated with the DNA vaccine and the bactericidal titer of the immune serum was deter mined by serum bactericidal assay ( SBA ) in vitro.Results: The recombinant pcDNA3.1 (+)/NMB0315 was effectively transcripted and expressed in eukaryotic cells and the specific humoral and cellular immune responses were induced in the inoculated mice .In the re-combinant pcDNA3.1(+)/NMB0315 group ,the levels of serum IgG,IgG1,IgG2a,IgG2b and IgG3 and genital tract sIgA were significantly higher than in controls ( P<0.001 ) .The stimulation index in the culture supernatant of the spleen lymphocytes of the vaccine group was higher than that of the control group (P<0.05).The ratios of serum IgG2a/IgG1 in the DNA vaccine group were less than 1.The bactericidal titer of the NMB 0315+CpG group reached 1:128 following three immunizations , the protection rate of the vaccine group was 70%against the N.meningitidis strain MC58.Conclusion:The NMB0315 nucleic acid vaccine could induce higher levels of humoral immunity and cellular immunity and showed effective protection against N .meningitidis serogroup B , the immune serum had strong bactericidal activity in vitro .
8.Clinical features of imported schistosomiasis mansoni in Beijing City:a re-port of 6 cases
Yang ZOU ; Lei WANG ; Xiaoli LI ; Xiaojun TIAN ; Wei LI ; Yijun AN ; Zhiqun QI ; Jingjing LI ; Fei WANG ; Minjun HUANG
Chinese Journal of Schistosomiasis Control 2017;29(2):150-154
Objective To analyze the clinical features of 6 patients with imported schistosomiasis mansoni,including the epidemic history,clinical manifestations,laboratory tests and therapeutic effect,so as to provide references for improving the levels of diagnosis and treatment of physicians. Methods The clinical data of 6 patients with imported schistosomiasis mansoni from January 2009 to July 2016 were collected and analyzed. Results All the 6 imported patients with schistosomiasis mansoni had a clear history of cercarial infested water exposure. The main manifestations were continuous fever and eosinophilia. Three (50%)patients were accompanied with diarrhea. Anti-Schistosoma japonicum IgG antibody were cross positive in 2(33.3%)pa-tients,while live eggs of S. mansoni were explored in intestinal mucosa specimens of all the patients. CD3+CD8+T cell ratio was decreased significantly but B cell ratio was elevated in all the patients,and the main immunoglobulin of the patients was IgG. Hydroperitoneum and splenomegaly signs were discovered by abdominal ultrasonography in 16.6%(1/6)of the patients. Multi-ple liver nodules and wall thickening of rectum and sigmoid colon were revealed by pelvic MR scan in 16.6%(1/6)of the pa-tients. Colitis was found in all the patients,and 66.6%(4/6)of the patients were combined with multiple colonic ulcers by the electronic colonoscopy examination. Chronic inflammation and eosinophil infiltration were found in all the patients by rectum pa-thology. All 6 patients were cured with chemotherapy named praziquantel. Conclusion Comprehensive analysis of clinical data including epidemiological history,specific manifestations,laboratory tests and intestinal mucosa pathology may be benefit of the management of schistosomiasis mansoni.
9.Construction of DNA vaccine with Neisseria gonorrhoeae porin B fused with B subunit of Escherichia coli heat-labile enterotoxin and study on its immune responses in mouse
Min CHEN ; Sihai HU ; Yufeng WANG ; Zhibing DAI ; Yukuai ZHANG ; Minjun YU ; Zhongyu LI ; Cuiming ZHU ; Chunxue LU
Chinese Journal of Infectious Diseases 2011;29(4):199-205
Objective To investigate the specific humoral immune response and cellular immune response induced by DNA vaccine with Neisseria gonorrhoeae porin B (PorB) fused with B subunit of Escherichia coli heat-labile enterotoxin B (LTB) in mice. Methods Target genes of porB, ltB and ltB-porB were amplified by polymerase chain reaction (PCR) and cloned into eukaryotic vector pcDNA3.1(-). The recombinants were identified by PCR, enzyme digestion and DNA sequencing.The vectors were transfected into Hela cells, and expressed proteins were checked by cytoimmunofluorescence. Female BALB/c mice were intranasally immunized with recombination vectors. The humoral immune response and cellular immune response were detected by enzyme linked immunosorbent assay (ELISA) and methyl thiazolyl tetrazolium (MTT) colorimetric assay. The expressions of recombination vectors in intranasal mucosal tissues of the immunized mice were detected by immunohistochemistry. The means between groups were compared by analysis of variance. Results All the three recombinants were expressed in Hela cells and intranasal mucosal tissues. The PorB specific IgG in serum and sIgA in vaginal secretions in DNA vaccine immunized mice were significantly higher than those in controls (P<0.01 ; P<0.05). Moreover, the sIgA level in pcDNA3.1 (-)/ltB-porB group was higher than that in peDNA3, 1(-)/porB group (P=0. 002). The levels of interferon-gamma (IFN-γ) and interleukin-4 (IL-4) in the supernatants and stimulation index (SI) of spleen lymphocyte culture in pcDNA3, 1(-)/porB group were (170.04±23.89) pg/mL, (114.68±14.27) pg/mL and 1. 68±0.19, respectively; and those in pcDNA3, 1(-)/ltB-porB group were (161.42±27.50) pg/mL, (124.16±19.04) pg/mL and 1.73±0.28, respectively; which were both higher than those in pcDNA3.1(-)/ phosphate buffered saliae (PBS) group (P<0. 01; P<0.05) and pcDNA3.1 (-)/ltB group (all P<0.05), while there was no significant difference between pcDNA3.1 (-)/ltB-porB group and pcDNA3. 1 (-)/porB group (0. 998, 0. 696, 0. 994; all P>0.05). Conclusions The constructed DNA vaccines are all successfully expressed in Hela cells and murine intranasal mucosal tissues. The mucosal immunization of the vaccines [pcDNA3. 1 (- )/porB and pcDNA3.1 ( -)/ltBporB] could induce humoral immune response and cellular immune response, especially mucosal immune response. It is confirmed that mucosal adjuvant LTB could promote PorB to induce higher level of mucosal immune response in mice.
10.Experimental study on the migration of vascular endothelial cells stimulated by IL-8.
Minjun ZOU ; Xiaoheng LIU ; Yi LI ; Yi LAI
Journal of Biomedical Engineering 2006;23(5):1013-1016
To investigate the influence of different concentrations of IL-8 on the migration of vascular endothelial cells and find out the best IL-8 concentration, the transwell chamber motility assay and the scrape motility assay were applied to observe the migration of vascular endothelial cells induced by IL-8. The results demonstrated that the migration of vascular endothelial cells was increased significantly under different IL-8 concentrations, while the best effect occurred when IL-8 concentration was 100 ng/ml.
Cell Movement
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drug effects
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Cells, Cultured
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Dose-Response Relationship, Drug
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Endothelial Cells
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cytology
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drug effects
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Endothelium, Vascular
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cytology
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Humans
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Interleukin-8
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administration & dosage
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pharmacology