- Li Fusheng; Zhang Zhiqing; Shao Hua et al (National Laboratory of Molecular Virology and Genetic Engineering, Beijing 100052)
The structure and function of GM-CSF was studied. The result showed that the amino acids 1～13 at the N-terminal of GM-CSF was not essential for its biological activ-ity, and interfered with the receptor binding. By using PCR technique, the amino acids 1～11 were deleted, and the amino acid 12 (Pro) was retained. The mutant GM-CSF cDNA was verified by whole DNA sequencing, then inserted into pBV220(a high experession prokaryot-ic vector) for expression. The expression level and stability of GM-CSF (12-127) mutant were significantly increased. The final GM-CSF (12-127) mutant protein was extracted from E. coli the inclusion body, and purified by hydrophobic and iron exchange chromatographies.The biological activity of the mutant protein reached 3 × 107U/mg protein, that was signifiantly higher than that cf GM-CSF protein. Receptor competitive binding test showed that the affinity of receptor binding of the mutant was significantly improved.
1996 03 [Abstract][OnlineView][Download 291k] - Pei Jin; Lu Chengyu; Li Zhichao et al (Preclinical Medical College,Norman Bethune Universi-ty of Medical Science, Changchun 130021 )
After mice were intravenously injected with 125I-IL-2 liposome and free 125I-IL-2, the drug distribution in their main organs and drug concentration -time curve were observed. The authors found that most of the IL-2 liposome were distributed in spleens and livers and released slowly. The clearance rate of IL-2 liposome in plasma was significantly lower than that of free IL-2, and the bioavailability of IL-2 liposome was significantly im-proved.
1996 03 [Abstract][OnlineView][Download 192k] -
1996 03 [Abstract][OnlineView][Download 42k] - Han Zhenguo; Ma Chang jin; Jiang W G et al (Third Teaching Hospital,Norman BethuneUniversity of Medical Science,Changchun 130031)
Cell dissociation, colony scattering and basement rnembrane invasion tests demonstrated that the motility and invasion of human lung cancer cells induced hy recombi-nant hepatocyte growth factor could be significantly inhibited by tumor Invasion inhibitingfactor-2 (IIF-2). The inhibition could be blocked by anti-IIF-2. The result showed that IIF-2 might have great significane on prevention and therapy of tumor metastasis-
1996 03 [Abstract][OnlineView][Download 211k] - Fu Pingping; Wang Weizhong; Zhao Hong et al (Third Teaching Hospital, Norman BethuneUniversity of Medical Science, Changchun 130021)
The components Ⅰ～Ⅴ of anti gastric-gland cancer IRNA were analysed by Raman spectrum. The result demonstrated that the Raman spectrums for components Ⅰ and Ⅱ were different from the other components. Under low salt concentration,each of the IRNA Ⅰ and Ⅱ showed both A and Z conformations, however, IRNA Ⅲ～Ⅴ showed A conforma-tion,
1996 03 [Abstract][OnlineView][Download 155k] - Han Liang; Zeng Guohua; Zhao Lixin et al (Changchun Institute of Biological Products,Changchun 130062)
The relationship between the antigenic epitopes of rHu-IFN-α 2a and its an-tiviral effect, as well as the mode of action of it on target cell receptor were studied by neu-tralization test, competitive ELISA and double McAb sandwich ELISA using the McAbs to rHu-IFN-α 2a prepared by the authors from 3 various cell strains. On the basis of the study,the following hypothesises was advanced: (1) IFN-α 2a molecule has only one antiviral active region; (2) There are at least 2 antigenic epitopes in the region; (3) The antiviral activity of IFN is the result of the action of whole active region on target cell receptors, and any single epitope in the region can not play antiviral role alone; (4) Each epitope in the region is very important for the antiviral activity, so any of them is indispensable.
1996 03 [Abstract][OnlineView][Download 150k] - Xue Weigang; Liu Dongsheng et al (Changchun Institute of Biological Products, Changchun 130062)
A recombinant virus strain was constructed by inserting the cDNA coding hu-man IL-4 into the end of polyhedral protein gene promotor of autographa californica nuclear polyhedrosis virus (Ac NPV). The expression level of IL-4 in the cell infected with the virus strain was relatively high, and the expressed IL-4, with a molecular weight of 16KDa,showed high biological activity.
1996 03 [Abstract][OnlineView][Download 315k] - Ren Zhenghua; Cui Jianhua (Third Teaching Hospital, Norman Bethune University of Medical Science, Changchun 130021)
Six cell strains secreting McAbs to IL-2 were obtained by hybridoma tech-nique and their characteristics were investigated. The titers of McAbs secreted by the 6 strains varied from 1∶10 to 10-5. The McAbs secreted by 5 of the 6 strains were IgG, and that secreted by the rest one was IgM. Significant and specific adsorption was found between the McAbs and purified IL-2 (p＜0．01). The McAbs secreted by 4 of the 6 strains have thesame absorption sites, but those secreted by the other 2 strains have at least 3 absorption sites with inconsistent steric hindrance.
1996 03 [Abstract][OnlineView][Download 132k] -
1996 03 [Abstract][OnlineView][Download 44k] - Duan Shumin; Li Fusheng; Yang Xinke ct al (National Laboratory of Molecular Virology and Genetic Engineering, Beijing 100052)
The recombinant human granulocyte-magrophage colony stimulating factor (rhGM -CSF) expressed in E, coli exists in the form of insoluble inclusion bodies. The inclu-sion bodies were separated from cytoplasm by ultrasonication. After denaturation and renatu-ration, they were purified by hydrophobic, ion exchange and gel filtration chromatographies.From SDS-PAGE pattern, the purity of final product reached 97. 8 %,and the specific activi-ty detected by MTT method using TF-1 cell reached 3×107 u/mg protein.
1996 03 [Abstract][OnlineView][Download 241k] - Zhang Yi; Rao Chungming; Ding Xishen (National Institute for the control of Pharmaceutical and Biological Products, Beijing 100050)
After the disulfide bond in rhEGF was reduced by DTT and the sulfydryl was blocked by idoacetanide, it was digested by trypsase treated with TPCK and analyzed by RP -HPLC. The minute difference among the structures of rhEGF expressed in various engi-neered bacterial strains was found. The method showed good sensitivity and repetitivity, andwas suitable for the routine peptide mapping of genetic engineered products.
1996 03 [Abstract][OnlineView][Download 110k]
1996 03 [Abstract][OnlineView][Download 177k] -
1996 03 [Abstract][OnlineView][Download 54k]
1996 03 [Abstract][OnlineView][Download 114k] -
1996 03 [Abstract][OnlineView][Download 241k]
1996 03 [Abstract][OnlineView][Download 183k] -
1996 03 [Abstract][OnlineView][Download 45k] 下载本期数据