[Application of a TRICIN-buffered modification of the CMRL-1969 medium in cell and virus cultivation (author's transl)]

Abstract

CMRL-1969 medium (Healy et al., 1971) was modified by using 0.02 molar N-[Tris-(hydroxymethyl)-methyl]-glycin (= TRICIN) instead of bicarbonate as the buffer substance. Several permanent cell lines and primary cell cultures did not show growth differences in the two medium variants. Like other non volatile buffers TRICIN abolishes the initial increase of the Ph in freshly split or newly fed closed vessel cultures, but in 0.02 M concentration maintains the same buffering capacity of the medium as compared to bicarbonate. Multiplication of Entero-, Adeno-, Herpes-, Influenza-A-, and Vaccinia-viruses was also not altered. The medium allows open vessel methods like microtiter- and plaque-tests to be conducted under normal atmosphere and seems especially useful when initial pH-values are to be set in the rank of 7.5 to 8.6. For microtiter neutralization tests with enteroviruses a medium adjusted to pH 7.6 and a cell density of 10(5) cells/cm2 was found optimal. Plaque formation of Coxsackie-B-viruses reached a maximal plaque-size and -number when the pH of the double concentrated medium was beyond 8.2.