REDUCTION OF AMMONIA FORMATION IN CELL-CULTURES BY L-ALANYL-L-GLUTAMINE REQUIRES OPTIMIZATION OF THE DIPEPTIDE CONCENTRATION

In cell culture media, glutamine (Gln) decomposes progressively into a mmonia and 5-pyrrolidone carboxylic acid. Ammonia is toxic and reduces cell growth. The formation of ammonia is strongly decreased by using the Gin dipeptide L-alanyl-L-glutamine (L-Ala-L-Gln). However, the eff ects of this dipeptide on the amount of ammonia originating from cellu lar Gin metabolism are not known. Growing microglial BV-2 cells in a m edium containing either Gin or L-Ala-L-Gln showed that the replacement of Gin by L-Ala-L-Gln, at concentrations much below those present in commercial media, was beneficial to the cell growth. Our approach coul d prove advantageous in culturing various types of cells. (C) 1998 Els evier Science B.V. All rights reserved.