Promotion of synthetic amyloid beta-peptide fibrillization by cell culture media and cessation of fibrillization by serum.

Dulbecco's modified Eagle's medium promotes aggregation and fibrillization of the synthetic amyloid beta 1-40 and beta 1-42 peptides more than RPMI and OPTI media. Fibrillization in all of these media is faster than in phosphate-buffered saline and Tris buffer. Normal and heat-inactivated fetal bovine and human serum abolish amyloid fibril formation in buffers and cell culture media. Fibrillar amyloid formed during 2-day-long incubation in cell culture media and buffers is defibrillized by 1-day-long treatment with human and bovine serum. This study indicates that amyloid beta fibrillogenesis in cell culture should be studied in serum-free media or in media with a low concentration of serum.