ABSTRACT
Objective:To construct and express the recombinant of human soluble TNF receptor I by E coli Methods:The cDNA coded for extracellular region of human TNFRI was amplified by RT PCR and inserted into a expression vector, pET 28a Then, the recombinant sTNFRI/pET 28a was transfected and expressed in E coli Results:After the stimulation with IPTG, sTNFRI fusion protein was effectively produced in E coli BL 21 transfected with the exogenous gene A unique band was found at 27 kD by SDS PAGE and its expression was about 31% of total protein in E coli The purified sTNFRI fusion protein was shown to be able to suppress the cytotoxicity of TNF on L929 cells and found by indirect immune fluorescence to inhibit specifically the binding of TNF with TNFR on target cells Conclusion:The recombinant human soluble TNFR I have been obtained by using the genetic engineering technology