AIM: To construct a phage display library of human singlechain variable fragment (scFv) antibodies associated with esophageal cancer and to preliminarily screen a scFvantibody against esophageal cancer.METHODS: Total ...AIM: To construct a phage display library of human singlechain variable fragment (scFv) antibodies associated with esophageal cancer and to preliminarily screen a scFvantibody against esophageal cancer.METHODS: Total RNA extracted from metastatic lymph nodes of esophageal cancer patients was used to construct a scFv gene library. Rescued by M13K07 helper phage, the scFv phage display library was constructed, esophageal cancer cell line Eca 109 and normal human esophageal epithelial cell line (NHEEC) were used for panning and subtractive panning of the scFv phage display library to obtain positive phage clones. Soluble scFv was expressed in E.coliHB2151 which was transfected with the positive phage clone, then purified by affinity chromatography.Relative molecular mass of soluble scFv was estimated by Western blotting, its bioactivity was detected by cell ELISA assay. Sequence of scFv was determined using the method of dideoxynucleotide sequencing.RESULTS: The size of scFv gene library was approximately 9×10^6 clones. After four rounds of panning with Eca109 and three rounds of subtractive panning with NHEEC cells,25 positive phage clones were obtained. Soluble scFv was found to have a molecular mass of 31 ku and was able to bind to Ecal09 cells, but not to HeLa and NHEEC cells.Variable heavy (VH) gene from one of the positive clones was shown to be derived from the γ chain subgroup IV of immunoglobulin, and variable light (VL) gene from the κ chain subgroup I of immunoglobulin.CONCLUSION: A human scFv phage display library can be constructed from the metastatic lymph nodes of esophageal cancer patients. A whole human scFv against esophageal cancer shows some bioactivity.展开更多
Objective To determine the distribution of HLA-B alleles in the Chinese Yi ethnic group and its association with HIV infection. Methods One hundred and six unrelated healthy HIV negative and 73 HIV positive Chinese Yi...Objective To determine the distribution of HLA-B alleles in the Chinese Yi ethnic group and its association with HIV infection. Methods One hundred and six unrelated healthy HIV negative and 73 HIV positive Chinese Yi ethnic individuals were typed by PCR-SSP. Results The frequency of alleles B*07, B*35, and B*46 were increased in HTV-1 -positive subjects, whereas the alleles B*55, B*44 and B*78 were absent in the HIV-infected persons studied. The B*46 allele was present in a significantly higher gene frequency among HIV-1-positive individuals (P=0.02, OR=3.32, 95% CI=1.13-9.78) compared with control subjects. Conclusion HLA-B*46 may be associated with its susceptibility to HIV-1 infections.展开更多
基金Supported by the National Natural Science Foundation of China,No.30070291 andNo.30213914 Medical Scientific Foundation of Guangdong Province,No.A2000434
文摘AIM: To construct a phage display library of human singlechain variable fragment (scFv) antibodies associated with esophageal cancer and to preliminarily screen a scFvantibody against esophageal cancer.METHODS: Total RNA extracted from metastatic lymph nodes of esophageal cancer patients was used to construct a scFv gene library. Rescued by M13K07 helper phage, the scFv phage display library was constructed, esophageal cancer cell line Eca 109 and normal human esophageal epithelial cell line (NHEEC) were used for panning and subtractive panning of the scFv phage display library to obtain positive phage clones. Soluble scFv was expressed in E.coliHB2151 which was transfected with the positive phage clone, then purified by affinity chromatography.Relative molecular mass of soluble scFv was estimated by Western blotting, its bioactivity was detected by cell ELISA assay. Sequence of scFv was determined using the method of dideoxynucleotide sequencing.RESULTS: The size of scFv gene library was approximately 9×10^6 clones. After four rounds of panning with Eca109 and three rounds of subtractive panning with NHEEC cells,25 positive phage clones were obtained. Soluble scFv was found to have a molecular mass of 31 ku and was able to bind to Ecal09 cells, but not to HeLa and NHEEC cells.Variable heavy (VH) gene from one of the positive clones was shown to be derived from the γ chain subgroup IV of immunoglobulin, and variable light (VL) gene from the κ chain subgroup I of immunoglobulin.CONCLUSION: A human scFv phage display library can be constructed from the metastatic lymph nodes of esophageal cancer patients. A whole human scFv against esophageal cancer shows some bioactivity.
基金This work was supported by the Special Funds for Major State Basic Research Program (973) of China (No.G1999054107) the National Key Technologies R & D Program of China during the 15th Five-years Plan Period (No. 2001BA705B02)
文摘Objective To determine the distribution of HLA-B alleles in the Chinese Yi ethnic group and its association with HIV infection. Methods One hundred and six unrelated healthy HIV negative and 73 HIV positive Chinese Yi ethnic individuals were typed by PCR-SSP. Results The frequency of alleles B*07, B*35, and B*46 were increased in HTV-1 -positive subjects, whereas the alleles B*55, B*44 and B*78 were absent in the HIV-infected persons studied. The B*46 allele was present in a significantly higher gene frequency among HIV-1-positive individuals (P=0.02, OR=3.32, 95% CI=1.13-9.78) compared with control subjects. Conclusion HLA-B*46 may be associated with its susceptibility to HIV-1 infections.
