ABSTRACT
To construct a scFv library by phage display technique from the spleen cells of mice immunized with B3HM cells. Three mice were immunized with B3HM cells, and their spleen cells were harvested. The genes of VH and Vk were amplified by RT-PCR from the cDNA of the immunized spleen cells and a scFv-phage display antibody library was constructed. The capacity of library was measured,and the variety of the library was analyzed by digesting with restriction endonuclease BstNI.ScFv phage clones were randomly picked and identified phage-scFv clone by binding B3HM cells using immunofluorescein.A scFv library containing 5?106 individual clones which showed different patterns after digested with restriction endonuclease BstNI was produced. Individnal phage-scFv clone showed B3HM cells positive using immunofluorescein. A scFv library of anti-B3HM cell surface molecules has been constructed. It will be useful for finding out some novel genes of causing leukemia, and establishs the infarctate foundation of clarifying the pathogenesis of leukemiagenesis.
ABSTRACT
In the present study, we inserted the core-streptavidin cDNA into downstream of multi-cloning site of plasmid pOPE101-8E5 by DNA gene recombination technology. And then, the variable fragments of heavy and light chain of the scFv-8E5 were replaced by the scFv-C4 variable fragments to construct the expression vector pOPE101-C4∷core-streptavidin. After transformed the vector pOPE101-C4∷core streptavidin into E.coil, the fusion protein C4∷core streptavidin-His-tag can be expressed by inducing with IPTG, and the expression level and activity of the expressed fusion protein analyzed by SDS-PAGE and Western blot. The results show that a scFv-C4∷core-streptavidin fusion protein of 45kDa was obtained, which can bind proteins of 60kDa & 45kDa from the KG1a cells lysate simultaneously. The binding function can be detected by the binding of core-streptavidin and biotin directly.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the in vivo effect of modified platelet factor 4 (PF4)-p17-70 cDNA on tumor angiogenesis in nude mice.</p><p><b>METHODS</b>The p17-70 cDNA was cloned into the AdEasy system to transfect packing cell line 293 and produce viral particles encoding p17-70cDNA (Ad p17-70). The integration of p17-70 cDNA was confirmed by RT-PCR and the P17-40 peptide Western blot. The biological activity of purified recombinant adenovirus was determined by umbilical veinal endothelial cell proliferation assay in vitro and in vivo tumor angiogenesis suppression of nude mice bearing human head and neck carcinoma.</p><p><b>RESULTS</b>p17-70 significantly inhibited in vitro proliferation of endothelial cells being 58% lower than that of empty vector and reduced tumor volume in vivo. The tumor mass was (0.086 +/- 0.054) g, (0.171 +/- 0.076) g and (0.195 +/- 0.067) g, the tumor volume was (16.7 +/- 5.2) mm(3), (36.5 +/- 23.7) mm(3) and (41.5 +/- 12.2) mm(3) in p17-70 cDNA transfected group, empty vector group and PBS group, respectively. Immunohistochemical staining demonstrated a decreased number of blood vessels in the tumors.</p><p><b>CONCLUSION</b>P17-70 peptide mediated by adenoviral vector could inhibit the endothelial proliferation in vitro and the tumor growth in vivo.</p>