[The immunopotentiation of human B lymphocyte stimulator C-terminal peptide].

The cDNA of human B lymphocyte stimulator C-terminal peptide (C-BLyS) was amplified by nested PCR from cDNA library of human fetal brain. The expression plasmid pT7450-C-BLyS was constructed and transformed into E. coli BL21 CodonPlus (DE3) RIL which can recognize many rare codons. The C-BLyS protein was expressed as inclusion body in E. coli BL21 CodonPlus (DE3) RIL and the inclusion body of C-BLyS was denatured and then refolded by dialysis and purified by ion exchange chromatography. The refolded and purified C-BLyS can specifically bind with BCMA-Fc, a fusion protein of BLyS receptor and human IgG1 Fc. Furthermore, C-BLyS is proved to be an effective stimulator in mouse splenocytes proliferation in vitro and effective immunostimulant in vivo.