CONSTRUCTION，EXPRESSION AND BIOLOGICAL ASSESSMENT OF BPI23—Fcγ1 RECOMBINANT PROTEIN PROKARYOTIC EXPRESSION VECTOR

INTRODUCTIONGram－negativesepsis（GNS）andinfectiousshockarechallengestocliniciansbecauseofhighmortality（１）．Routineantibiotictherapydoesnotworkwellbe－causeoftheincreasingoccurrenceofresistantstrainsand（２）．Anti－lipopolysaccharide（LPS）monoclonal

Construction, expression and biological assessment of BPI23-Fcgamma1 recombinant protein prokaryotic expression vector.

OBJECTIVE: To construct pBV-BPI600-Fcgamma1(700) recombinant expression vector, to transform it into Escherichia coli DH5alpha, and to induce the expression of BPI23-Fcgamma1 anti-bacterial recombinant protein. METHODS: Genes coding for BPI23 and Fcgamma1 were amplified by RT-PCR from mRNA extracted from HL-60 cell and normal human leukocytes; recombinant cloning vector and recombinant expression vector were then constructed. pBV-BPI600-Fcgamma1(700) recombinant expression vector was transformed into the competent Escherichia coli DH5alpha and BPI23-Fcgamma1 recombinant protein was expressed by a temperature-induced method. RESULTS: (1) Expected amplified products BPI600hp and Fcgamma1(700bp) were obtained by RT-PCR method. (2) pUC18-BPI180, pUC18-BPI420 and pUC18-Fcgamma1(700) recombinant cloning vector were successfully constructed, and sequences were identical with the reported ones. 3) pBV-BPI600-Fcgamma1(700) recombinant expression vector was successfully constructed, and the enzyme digestion analysis showed an expected result. (4) The expression level of BPI23-Fcgamma1 recombinant protein accounted for 20% of total bacterial proteins. (5) The renatured BPI23-Fcgamma1 recombinant protein showed bacteriocidal activity and biological function of complement fixation, and opsonization. CONCLUSION: pBV-BPI600-Fcgamma1(700) recombinant expression vector was successfully constructed, and BPI23-Fcgamma1 recombinant protein with double biological activity of BPI and IgGFc was expresed in Escherichia coli.