A minimal medium for the cultivation of infective Trypanosoma cruzi epimastigotes.

In a culture medium containing bovine liver catalase, but lacking exogenous free amino acids, only two vitamins (choline and folic acid) were found to be essential for the continuous in vitro multiplication of seven different infective strains of Trypanosoma cruzi. The provision of additional vitamins or sugars had no stimulatory effect under these culture conditions. These, and previous studies, have allowed the design of a trypanosomal minimal medium composed only of bovine liver catalase, choline, folic acid, glucose and inorganic salts. This was able to support the continuous cultivation of T. cruzi for more than 12 consecutive passages (i.e. about 160 d of culture). By several criteria, namely morphological features as seen by electron microscopy, infectivity for vertebrate and invertebrate hosts, glucose utilization and protein biosynthesis, this medium (which is the simplest so far described) proved to be nutritionally adequate for Trypanosoma spp. In addition, the medium appeared to be relatively specific for T. cruzi, as it did not support the growth of T. rangeli and American isolates of leishmania.