A serum-free medium (SFM-MDM) without any animal-driven protein was developed for the production of recombinant antibody in suspension cultures of recombinant Chinese hamster ovary cell line, CS*13-1.00. The formulation of SFM-MDM was based upon the Iscove's modified Dulbecco's medium (IMDM), and Long (TM) R(3)IGF-1 and ferric citrate were supplemented instead of insulin and transferrin. Among various protein hydrolysates, yeast extract was selected as a serum-substituting additive for the improvement cell growth and productivity of recombinant antibody. Through about 3600 h of adaptation period from conventional SFM to SFM-MDM, integral of viable cell density and specific antibody productivity increased from 7.60 x 10(6) cells d and 19.14 mu g (10(6) cells d)(-1) to 7.79 x 10(6) cells d and 54.04 mu g (10(6) cells d)(-1), respectively, resulted in final antibody concentration of 420.98 mg l(-1), which was about three times higher than that obtained from commercial medium, 486F Also, supplementation of various vitamins including biotin, pyridoxal(.)HCl, and ascorbic acid was observed to enhance specific productivity, which led to high final antibody concentration. These results suggested the fundamental and effective strategy for development of a serum-free medium and to enhance cell growth and production of target proteins. (c) 2006 Elsevier Inc. All rights reserved.