Expression and Purification of a Novel Influenza Virus Subunit Vaccine / 中国生物工程杂志

The influenza A virus matrix protein2 gene(M2)which deleted transmembrane region was amplified by overlap extending PCR,and the multiepitope gene of hemagglutinin(HA)was PCR amplified with seven continuous synthesized segments by designing primer.The two gene segments were separately cloned into pMD18T vector to sequence analysis and prokarytic expression vector pET28a+ to construct the recombinant plasmid pET28a+M2dHA.The recombinant plasmid was transformed into E.coli BL21(DE3),and the high expression strain was obtained by screening monoclones.The recombinant protein existed as inclusion bodies,which accounted about 45% of the total cellular protein.The inclusion bodies were washed with 1% Triton X100 solution twice,and dissolved in 8 mol/L urea solution.The solution protein was purified by Ni+2 affinity chromatography,and refolded by dilution renaturation,then purified by Q Sepharose FF cation exchange column.The purity of the protein was over 90% by HPLC analysis.The result of Western blot showed it has good antigenicity and specificity.These results strongly supported for the further study of the broadspectrum influenza virus subunit vaccine.

Expression of ITF Gene in Lacococcus lactis / 中国生物工程杂志

To develop an oral drug,ITF gene encoding ITF proein,was expressed in a live delivery vehicle lactococcus lactis.First,the ITF gene was cloned into the prokaryotic expressive vector pNICE:sec.Second,the recombinant vector pNICE:sec-ITF was transformated into Lactococcus lactis strain NZ9000 to express ITF protein.Then the recombinant ITF was induced to express and was identified by SDS-PAGE and Western blot.Rabbits are divided into blank control group,preparation group and therapeutic group which are respectively administrated wih PBS and pNICE:sec-ITF Lactococcus lactis.By grades of ulcer test whether administrated pNICE:sec-ITF Lactococcus lactis protects against HCl-induced gastric injury in rabbits.The results were described as follows.The ITF was amplified and cloned in the vector pNICE:sec successfully.The fusion protein(5.9kDa) was expressed in L.lactis by the induction of the nisin.The quantity of expression accounted for 5% of the total bacterial protein.Western bolt analysis confirmed that fusion protein could be recognized specially by Monoclonal Anti-human TFF3 Antibody.Preparation groups and therapeutic groups do good than control group.Prove that administrated pNICE:sec-ITF Lactococcus lactis is biologically active in an HCl-induced rabbit gastric mucosal injury model.

Expression and Immune Effect Study of Therapeutic Recombinant Protein Vaccine VP22?-mE6?/mE7 / 中国生物工程杂志

In order to investigate the biological effects of the VP22?-mE6?/mE7 built-in adjuvant fusion protein vaccine on the tumor associated with HPV-16 infection.HSV-1 VP22? and HPV-16 mE6?/mE7 genes were cloned,and the pET28a-VP22?-mE6?/mE7 recombinat prokaryotic expression vector was constructed.Vector was transformed into Rosetta(DE3)E.coli string and expressed under the induction of IPTG.The re-naturalized protein was then purified via Ni2+ affinity adsorbent column and identified by SDS-PAGE and Western blot.Purified protein was immunized BalB/C and C57BL/6 mice to evaluate the immunogenicity and anti-tumor activity.The expressed recombinant protein formed as inclusion body with a prediction MW about 34kDa and contained approximately 45% of total somatic protein.The VP22?-mE6?/mE7 immunization induced higher titer of specific IgG against HPV,higher level of lymphocyte proliferation and better effect on suppressing HPV16 positive TC-1 tumor growth than the mice immunized with mE6?/mE7 alone.The results showed that the recombined built-in adjuvant vaccine could induce specific cellular immune response in vitro and inhibit the TC-1 tumor proliferation in vivo,that would be a foundation for further studies and developments of inner adjuvant vaccines.

Preparation and Pegylation of TNF-? Derivative / 中国生物工程杂志

The gene of mutated TNF-?D4 gene was amplified by overlap PCR and cloned into the prokaryotic expressive vector pBV220.TNF-?D4 contains two changes:substitutions of Pro8Arg,Ser9Lys,Asp10Arg,Ile157Phe,Leu29Ser,Arg31Val and a deletion of the N terminal four amino acids.The recombinant vector pBV220-TNF-?D4 was transformated into E.coli strain DH5?,and the high expression strain was obtained by screening monoclones.The level of expression was about 45% of total cell protein.After purification,the purity of fusion protein was above 90% by HPLC and relative ability was 8 ?107.TNF-?D4 was modificated by mPEG-ButyrALD。After purification,the purity of mPEG-TNF-?D4 was above 85% and relative ability was 8.6?107.The in vivo systemic toxicity of mPEG-TNF-?D4,which is indicated by LD50,is lower than that of rhTNF-?.These results strongly supported for the further study and exploitation of TNF-antitumor drug.