THE REQUIREMENT FOR HYDROCORTISONE IN ANTIBODY-FORMING TISSUE CULTIVATED IN SERUM-FREE MEDIUM

Abstract

Evidence is presented to show that physiological levels of hydrocortisone (0.01 to 1.0 [mu][image]) can substitute for serum in the culture medium. However, with the omission of serum, serine (0.1 mM) must be included among Eagle''s "essential" amino acids for consistent optimal antibody production. In some experiments the addition of insulin (0.5 unit/ml) and vitamin B12 (0.5 [mu]g/ml) has further enhanced the secondary response in this serum-free medium.