Application of a new medium supplement for propagation and storage of human cytomegalovirus

A new medium supplement, NU-SERUM, was evaluated for cultivation of human embryonic lung fibroblasts (HEL) and for propagation and storage of human cytomegalovirus (HCMV). NU-SERUM was comparable to fetal bovine serum (FBS) in promoting rapid growth of HEL if they were seeded at a sufficient density. HCMV replicated quite satisfactorily in HEL cultured with media supplemented with NU-SERUM as well as FBS. Inactivation of HCMV at 37 C occurred similarly when the medium contained FBS or NU-SERUM. However, at -70 C, HCMV was less stable in NU-SERUM-containing medium than in FBS-containing medium. Sorbitol added to the NU-SERUM-containing medium improved the unstableness of HCMV at -70 C, and HCMV was storable with such medium. Thus, NU-SERUM is useful as an alternative to FBS not only for growth of HEL but also for propagation and storage of HCMV.