| 摘要 |
NEW MATERIAL:The title human BCDF where one or both of the aspartic acid at the 140th site and proline at the 141th site from the N-terminal of the factor (BCDF) capable of differentiating natural-type human B-cells into antibody-productive cells replaced by other amino acid(s). USE:A therapeutic agent for immunodeficiency, cancer, thrombocytopenia, autoimmune diseases etc. A hematopoietic. PREPARATION:For example, plasmid pBSF-2D containing a gene coding natural- type human BCDF is cut with restriction enzymes EcoRI and Pvu II and bound to an appropriate DDN fragment and then cut again with restriction enzymes Hind III and Ban II, and bound again to an appropriate DNA fragment. The product is cut with restriction enzymes Pvu II Bam HI and TthHB 81 and bound to an appropriate DNA fragment and cut further with restriction enzyme Pvu II and bound further to a synthesized DNA fragment, thus the aspartic acid at the 140th site from the n-terminal of the natural-type human BCDF is changed to asparagine, and the resulting human BCDF is then introduced into Escherichia coli followed by incubation, thus obtaining the objective variant human BCDF. |
