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Guang-Yu Li

Publications and source records attributed to Guang-Yu Li.

8 recordsLinked to original sources
PubMed2006

Expression of dendritic cell-specific intercellular adhesion molecule 3 grabbing nonintegrin on dendritic cells generated from human peripheral blood monocytes.

AIM: To generate dendritic cells (DCs) from human peripheral blood and to detect the expression of dendritic cell-specific intercellular adhesion molecule 3 grabbing nonintegrin (DC-SIGN; CD209) for the further study of DC-SIGN in hepatitis C virus (HCV) transmission. METHODS: Peripheral blood monocytes were isolated from blood of healthy individuals by Ficoll-Hypaque sedimentation and cultured in complete medium containing rhGM-CSF and rhIL-4. Cells were cultured for seven days, with cytokine addition every two days to obtain immature DCs. Characteristics of the cultured cells were observed under light and scanning microscope, and the expression of DC-SIGN was detected by immunofluorescence staining. RESULTS: After seven-day culture, a large number of cells with typical characteristics of DCs appeared. Their characteristics were observed under light and scanning electron microscope. These cells had a variety of cell shapes such as those of bipolar elongate cells, elaborate stellate cells and DCs. DC-SIGN was detected by immunofluorescence staining and its expression level on cultivated dendritic cells was high. CONCLUSION: DCs with a high expression of DC-SIGN can be generated from human peripheral blood monocytes in complete medium containing rhGM-CSF and rhIL-4.

Animals↗
PubMed2005

Stable inhibition of hepatitis B virus expression and replication by expressed siRNA.

RNA interference might be an efficient antiviral therapy for some obstinate illness. Here, we studied the effects of hepatitis B virus (HBV)-specific 21-nt small interfering RNAs (siRNA) on HBV gene expression and replication in 2.2.15 cells. Seven vectors expressing specific hairpin siRNA driven by the RNA polymerase II-promoter were constructed and transfected into 2.2.15 cells. In the cell strain that can stably express functional siRNA, the HBV surface antigen (HBsAg) and the HBV e antigen (HBeAg) secretion into culture media was inhibited by 86% and 91%, respectively, as shown by an enzyme-linked immunosorbent assay. Immunofluorescence and Western blot indicated similar results. HBV DNA was markedly restrained by 3.28-fold, as assessed by the fluorescent quantitation PCR. Moreover, the HBV mRNA was significantly reduced by 80% based on semiquantitative RT-PCR. In conclusion, the specific siRNA can knock down the HBV gene expression and replication in vitro, and the silence effects have no relationship with interferon response.

Cell Line, Tumor↗
PubMed2005

Effect of anti-tuberculosis therapy on liver function of pulmonary tuberculosis patients infected with hepatitis B virus.

AIM: To observe the effect of anti-tuberculosis therapy on liver function of pulmonary tuberculosis patients with hepatitis B virus (HBV) infection, and to compare the differences of liver function by two treatments of anti-tuberculosis. METHODS: Forty-seven TB patients with HBV infection and 170 TB patients without HBV infection were divided into HPBE(S) and HLAMKO treatment groups. Liver function tests before and after the treatments were performed once in 2 wk or monthly, and their clinical manifestations were recorded. RESULTS: The rate of hepatotoxicity occurred in 26 (59%) TB patients with HBV during anti-TB treatment, higher than that in 40 (24%) TB patients without HBV. Hepatotoxicity occurred in 66 out of 217 patients, and the incidence of liver dysfunction was 46.1% in HPBE(S) group, significantly higher than that in HLAMKO group (12.7%) (P<0.01). CONCLUSION: TB patients with HBV should choose HLAMKO treatment because of fewer hepatotoxicity.

Adult↗
PubMed2005

[Changes of expression of HIF-1alpha in the human retinal pigment epithelium induced by hypoxia].

OBJECTIVE: To investigate the expression of HIF-1alpha in human retinal pigment epithelium (hRPE) induced by hypoxia at different time points and to study the mechanism of choroidal neovascularization. METHODS: hRPE were isolated, cultured and identified. The changes of level of mRNA and protein of HIF-1alpha in hRPE at different time points after exposed to hypoxia were measured by semi-quantitative RT-PCR and immunofluorescence techniques. RESULTS: A significant increase of HIF-1alpha level in cultured hRPE was induced by hypoxia. After 8 hours exposed to hypoxia, the level of HIF-1alpha in the hRPE reached a peak and sustained for more than 16 hours. After a prolonged exposure to hypoxia, the morphology of hRPE began to change and the HIF-1alpha level was decreased. CONCLUSIONS: The level of HIF-1alpha in hRPE rises obviously after exposed to hypoxia. This may play a role in the occurrence of choroidal neovascularization.

Cell Hypoxia↗
PubMed2004

[The relationship between cellular infection by Hantaan virus and expression of beta3 integrin].

OBJECTIVE: To investigate the relationship between cellular entry of Hantaan virus (HTNV) and expression of beta3 integrin in beta3-integrin-deficient and HTNV-insusceptible China hamster ovary (CHO) cells. METHODS: Eukaryotic expression vector encoding human integrin beta3 and eukaryotic expression vector harboring human integrin alphav or alphaIIb subunit cDNA were transfected into HTNV non-permissive CHO cells individually or collectively. Screening for stable transfectant clones was performed using G418 selective (culture medium. The exogenous gene expression was analyzed qualitatively and quantitatively by immunofluorescence assay (IFA) and flow cytometry (FCM). Various modified CHO cells and untransfected CHO cells were infected using HTNV A9. At various time points after infection, HTNV antigens in infected cells were detected qualitatively and quantitatively by IFA, FCM. RESULTS: Highly-effective surface expression of beta3 integrin was measured in CHO/alphavbeta3 and CHO/alphaIIbbeta3, while weaker surface expression was detected in CHO/beta3 (P < 0.05). Expression of alphav or alphaIIb integrin in the individually transfected group was significantly lower than in the cotransfected group (P < 0.01) and the sites of localization changed. In contrast, effective surface expression was not seen when pcDNA3 was transfected alone. The infection rate of CHO/alphavbeta3 (60.1%) and CHO/alphaIIbbeta3 (55. 9%) cells were significantly higher than that of CHO/beta3 (38.7%) cells, while the infection rate of CHO/beta3 was significantly higher than that of CHO/alphav, CHO/pcDNA3 and CHO cells respectively. There was a close relationship between the positive percentage of HTNV A9-infected cells and expression of beta3 integrin. CONCLUSION: These results indicated that cellular entry of HTNV was related to the expression of beta3 integrin.

Animals↗
PubMed2003

HBV DNA vaccine with adjuvant cytokines induced specific immune responses against HBV infection.

AIM: To seek for an effective method to improve the immune responses induced by DNA vaccine expressing HBV surface antigen (pCR3.1-S) in Balb/c mice (H-2(d)). METHODS: The pCR3.1-S plasmid and the eukaryotic expression vectors expressing murine IL-2 (pDOR-IL-2) or IL-12 (pWRG3169) were injected into mice subcutaneously. The immune responses to pCR3.1-S and the adjuvant effect of the cytokines plasmid were studied. Meanwhile the effect of pCR3.1-S on anti-translated subcutaneous tumor of P815 mastocytoma cells stably expressing HBsAg (P815-HBV-S) was also studied. Anti-HBs in serum was detected by enzyme-linked immunoadsorbent assay (ELISA) and HBsAg specific cytotoxic T lymphocytes (CTLs) activity was measured by (51)Cr release assay. After three weeks of DNA immunization, the cells of P815-HBV-S were inoculated into mice subcutaneously and the tumor growth was measured every five days. The survival rate and living periods of mice were also calculated. RESULTS: After 8 wk DNA immunization, the A 450 nm values of sera in mice immunized with pCR3.1, pCR3.1-S and pCR3.1-S codeliveried with IL-2 or IL-12 plasmids were 0.03+/-0.01, 1.24+/-0.10, 1.98+/-0.17 and 1.67+/-0.12 respectively. Data in mice codeliveried pCR3.1-S with IL-2 or IL-12 plasmids were significantly higher than that of mice injected pCR3.1 or pCR3.1-S only. The HBsAg specific CTL activities in mice coinjected with pCR3.1-S and IL-2 or IL-12 eukaryotic expression vectors were (61.9+/-7.1) % and (73.3+/-8.8) %, which were significantly higher than that of mice injected with pCR3.1 (10.1+/-2.1) % or pCR3.1-S (50.5 +/-6.4) %. The HBsAg specific CTL activities in mice injected with pCR3.1, pCR3.1-S, pCR3.1-S combined with IL-2 or IL-12 eukaryotic expression vectors decreased significantly to (3.2+/-0.8) %, (10.6+/-1.4) %, (13.6+/-1.3) % and (16.9+/-2.3) % respectively after the spleen cells were treated by anti-CD8(+) monoclonal antibody, but presented no significant change to anti-CD4(+) monoclonal antibody or unrelated to monoclonal antibody. The HBV-S DNA vaccine (pCR3.1-S) could evidently inhibit the tumor growth, prolong the survival period of mice and improve the survival rate of mice and these effects could be improved by IL-12 gene codeliveried. CONCLUSION: HBV DNA vaccine has a strong antigenicity in humoral and cellular immunities, which can be promoted by plasmid expressing IL-2 or IL-12. CD8+ cells executed the CTL activities. DNA vaccine may be useful for both prophylaxis and treatment of HBV infection.

Adjuvants, Immunologic↗
PubMed2003

[Construction of human integrin beta3 subunit eukaryotic expression vector and efficient surface expression of integrin alphaIIbbeta3].

AIM: To establish efficient surface expression of Homo sapiens integrin alphaIIbbeta3 in beta3-integrin-deficient and HV-insusceptible CHO cells, so as to lay the foundation for the further study of cellular entry of hantavirus mediated by beta3 integrins. METHODS: Eukaryotic expression vector pcDNA3.1-beta3 harboring ORF region of human integrin beta3 subunit cDNA was constructed, then pcDNA3.1-beta3 and eukaryotic expression vector pBJ1-alphaIIb containing human integrin alphaIIb subunit cDNA were transfected into CHO cells alone or together. The expression of exogenous genes were analyzed by indirect immunofluorescence assay (IFA). RESULTS: The eukaryotic expression vector pcDNA3.1-beta3 was constructed successfully. IFA examination showed that surface expression of integrin alphaIIb beta3 was highly effective in cotransfection group, while surface expression was weak on CHO cells transfected with pcDNA3.1-beta3 alone,and no effective surface expression was found in pBJ1-alphaIIb-transfected group. CONCLUSION: Efficient surface expression of integrin alphaIIb beta3 requires expression of both subunits.

Animals↗