HUMAN B CELL DIFFERENTIATION FACTOR

摘要

PURPOSE:To identify the gene governing the production of BCDF, to determine the structure of BCDF molecule and to enable mass-production of BCDF using recombinant DNA technique, by separating BCDF mRNA from a human cell having high productivity of BCDF. CONSTITUTION:DNA extracted from normal human placenta is digested with PvuII or PstI. A BamHI-AccI fragment of plasmid pSP6k-mTRF23 cloned with the gene of mouse B cell differentiation factor (BCDF) is used as a probe and a clone hybridizing therewith is selected from the digested DNA. The cloning of human BCDF cDNA is ascertained as to the plasmid of said clone and the base sequence of said DNA is determined. The base sequence of obtained cDNA is compared with that of mouse BCDF gene to determine the region coding human BCDF polypeptide and an amino acid sequence. A human BCDF is produced by using the prepared gene sequence.