Rapid methods for purification of human recombinant interleukin-5 (IL-5) using the anti-murine IL-5 antibody-coupled immunoaffinity column.

A large scale production of human recombinant IL-5 (hIL-5) was performed by way of recombinant DNA technology. In this study, we transfected Chinese hamster ovary cells with pdKCR-hIL-5gene-dhfr plasmid and selected a cell line, with the use of methotrexate, producing large amounts of hIL-5. The recombinant hIL-5 thus obtained induced IgM production of murine B cell leukemia BCL1, and its activity was inhibited by TB13 anti-mouse IL-5 monoclonal antibody. hIL-5 could be purified from the cell-free supernatants of the transfectants with high recoveries by using anti-mouse IL-5 antibody-coupled immunoaffinity column in combination with a gel permeation column chromatography. N terminal amino acid sequence analysis of purified hIL-5 revealed that a single amino-terminal amino acid (isoleucine) is detected and hIL-5 consists of 115 amino acid residues.