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Xiao-hong Chang

Publications and source records attributed to Xiao-hong Chang.

6 recordsLinked to original sources
PubMed2006

Humoral immune responses induced by anti-idiotypic antibody fusion protein of 6B11scFv/hGM-CSF in BALB/c mice.

BACKGROUND: We have previously developed and characterized a monoclonal anti-idiotype antibody, designated 6B11, which mimics an ovarian carcinoma associated antigen OC166 - 9 and whose corresponding monoclonal antibody is COC166 - 9 (Ab1). In this study, we evaluate the humoral immune responses induced by the fusion protein 6B11 single-chain variable fragment (scFv)/human granulocyte macrophage colony-stimulating factor (hGM-CSF) and 6B11scFv in BALB/c mice. METHODS: The fusion protein 6B11scFv/hGM-CSF was constructed by fusing a recombinant single-chain variable fragment of 6B11scFv to GM-CSF. BALB/c mice were administrated by 6B11scFv/hGM-CSF and 6B11scFv, respectively. RESULTS: The fusion protein 6B11scFv/hGM-CSF retained binding to the anti-mouse F (ab) 2' and was also biologically active as measured by proliferation of human GM-CSF dependent cell TF1 in vitro. After immunization with the 6B11scFv/hGM-CSF and 6B11ScFv, BALB/c mice showed significantly enhanced Ab3 antibody responses to 6B11scFv/hGM-CSF compared with the 6B11scFv alone. The level of Ab3 was the highest after the first week and maintained for five weeks after the last immunization. Another booster was given when the Ab3 titer descended, and it would reach to the high level in a week. CONCLUSION: The fusion protein 6B11scFv/hGM-CSF can induce humoral immunity against ovarian carcinoma in vivo. We also provide the theoretical foundation for the application of the fusion protein 6B11scFv/hGM-CSF for active immunotherapy of ovarian cancer.

Animals↗
PubMed2006

[Study of immunization protocol of ovarian carcinoma associated 6B11 anti-idiotypical minibody].

OBJECTIVE: To probe better immunization dose and interval of anti-idiotypical minibody (6B11 minibody) in animals and to guide the clinical trials of ovarian epithelial cancer treatment. METHODS: Minibody was induced with isopropylthiogalactoside (IPTG) in E.coli and analyzed with direct enzyme linked immunosorbent assay (ELISA). Normal BALB/c mice were randomly divided into groups A, B, C, D, E, F, immunized with the murine monoclonal anti-idiotypic antibody 6B11 minibody 150 microg, 100 microg, 50 microg, and mice IgG 100 microg, human IgG 100 microg, phosphate buffered saline (PBS) 100 microl at d(1), d(14), d(28) respectively. Anti-anti-idiotypic antibody (Ab3) level was tested and antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) effect of mouse spleen cells to human ovarian carcinoma SKOV3 cells were measured using (51)Cr-release assay. UV absorption values were tested at 490 nm. RESULTS: 6B11 minibody was successfully expressed on E.coli and could react with a murine monoclonal antibody COC166-9. Ab3 could not be detected until one week after d(14)'s boost, its level gradually elevated and peaked one week after d(28)'s boost, and maintained at high level for about six weeks then declined dramatically seven weeks after d(28)'s boost. When boosted again at seven weeks after d(28)'s boost, the Ab3 level elevated quickly one week after, and maintained at this level at least for two weeks. The Ab3 level of group B was higher than groups A and C, mean A (absorption) value during six weeks after d(28)'s boost was 1.05 in group A, 1.06 in group B, 0.94 in group C, and there was no significant difference (P > 0.05). At four different effector cell/target cell (E/T) ratios, the ADCC was highest in group A and lowest in group C; when the E/T ratio was 1:125, (51)Cr releasing rate was 23% in group A, 17% in group B, and 12% in group C, the difference between groups A, B, C had statistical significance (P < 0.05). When serum was diluted at 1:50, the CDC effects were higher in group A and B than in group C ((51)Cr releasing rate was 47%, 39%, 26% respectively; P < 0.05), but there was no significant difference between groups A and B (P > 0.05). CONCLUSION: 6B11 anti-idiotypic minibody of ovarian carcinoma can be used as tumor vaccine, the suitable immunization protocol in animals may be: prime at d(1), d(14) and d(28) at a dose of 100 microg; prime interval is six weeks.

Animals↗
PubMed2005

[In vitro study of the antitumor immune responses induced by anti-idiotypic minibody vaccine of ovarian cancer].

OBJECTIVE: To evaluate whether anti-tumor immune response can be induced in vitro with 6B11 anti-idiotypic minibody. and to explore its probability as ovarian cancer vaccine. METHODS: Separated human peripheral blood mononuclear cells (PBMC) were stimulated and cultured by 6B11 minibody. The proliferations of PBMC and cytotoxin were observed by (3)HTdR and (51)Cr release test respectively. ELISA(Enzyme-Linked Immunosorbent Assay) test and Immune Flow Cytometry were used to analyze IFN-gamma in supernatant of the cultured cdlls and the change of T lymphocyte phenotype of PBMC with 6B11 minibody stimulated. RESULTS: 6B11 minibody could stimulate PBMC to proliferate, the best dose was 20 mg/L; it performed cytotoxin function to ovarian carcinoma cell line expressing OC166-9. IFN-gamma maintained at high level after stimulation. It stimulated proliferation of CD3(+) T cell and CD4(+) from PBMC after stimulation respectively. CD8(+) T cell proliferation was not clear. There was significant difference between stimulation and unstimulation in CD4(+)/CD8(+) ratio. CONCLUSION: 6B11 anti-idiotypic minibody can induce both humoral and cellular immunity against ovarian carcinoma in vitro. This paper has provided strong experimental evidence for clinical use of 6B11 minibody as anti-idiotype vaccines against ovarian carcinoma.

Antibodies, Anti-Idiotypic↗
PubMed2003

[Monitoring novel ovarian carcinoma associated genes using cDNA expression microarray].

OBJECTIVE: To explore the gene expression pattern of sample of human ovarian carcinoma. METHOD: The difference in gene expression between normal and neoplastic human ovarian tissues were investigated, we described the assembly and utilization of a 512 member cDNA microarray. RESULT: Thirty-seven genes expressed in ovarian cancer were screened out, 14 genes were up-regulated, 23 genes were down-regulated. CONCLUSION: cDNA microarray for analysis of gene expression pattern is an effective method to identify novel ovarian cancer associated genes.

Female↗
PubMed2003

[Immuno-therapeutic study of anti-idiotype minibody (single chain Fv-CH3) on ovarian carcinoma bearing mice].

OBJECTIVE: An anti-idiotypic minibody with optimal antigenicity which mimicking ovarian cancer antigen was used for therapeutic research in mice model bearing ovarian cancer. METHODS: Using gene engineering technique, prokaryotic expression vector was constructed by genetic fusion of 6B11scFv to human IgG1 hinge and CH3 region. The fusion protein named minibody was induced with IPTG in E. coli and analyzed with Western blot and inhibition ELISA tests respectively. Twenty human-PBL-SCID mice bearing i.p. Skov3.ip1 cells were divided into two groups (10 per-group), 10 mice were immunized repeatedly by minibody every two weeks for three times. Indirect ELISA test was employed for analyzing the characterization of anti-anti-idiotypic scFv (Ab3). The latent period of ascites growth and the mean survival time were observed respectively. CD4+ and CD8+ T cells from the spleen of immunized mice were assayed by flow cytometry. RESULTS: SDS-PAGE gel electrophoresis showed that a protein band with molecular weight of 50,000 appeared as the expected size after transformation and induction the host bacteria BL21 (DE3). The expressed minibody could be reacted with COC166-9 (Ab1 of 6B11) and binding goat anti-human IgG1 antibody in Western blot. Inhibition ELISA showed minibody had the capacity of binding ovarian cancer monoclonal antibody COC166-9 instead of primal antigen. Ab3 could be detected in the sera of immunized mice with minibody by ELISA test. Ab3 reached the highest at the 14th day after last vaccination and lasted for 6 weeks. The ratio of CD4+/CD8+ was the highest at the 13th day after last vaccination. The latent period of ascites growth were (37.7 +/- 5.5) days and (48.6 +/- 14.3) days (P = 0.04) respectively; while the mean survival time were (42.5 +/- 1.8) days and (59.4 +/- 16.8) days (P = 0.011) in the control and minibody group respectively. CONCLUSIONS: These results demonstrate the successful construction and expression minibody with good immune activities of 6B11scFv and human IgG1 molecules function. Antigenicity is increased without adjuvants and partial humanization is realized. Minibody can induce humoral anti-idiotypic immunity responses against ovarian carcinoma in vivo. When ascites formation was delayed or prevented and the survival was prolonged in minibody group. We expect that minibody may be used as tumor vaccine to ovarian carcinoma in the future clinical trails.

Animals↗