In vitro cultivation of Trypanosoma acomys: production of insect stages and bloodstream forms: production of insect stages and bloodstream forms

When Trypanosoma acomys bloodstream forms were cultivated at 37° C in Schneider's Drosphila medium supplemented with 20% (v/v) heat-inactivated foetal calf serum (FCS), with Microtus agrestis embryonic fibroblasts in RPMI 1640 medium supplemented with 20% FCS or in Baltz's medium supplemented with 10% FCS, the parasites transformed and largely remained as epimastigotes. Epimastigotes were also usually the commonest stage observed when the parasites were co-cultivated with a mosquito cell line at 27° C. However, if these cultures were initiated with the supernatant suspensions from fibroblast cultures that had been cryopreserved, trypomastigotes, including blood-stream-like forms, were the predominant stage for the first 4 days of culture. It is suggested that the glycerol supplement or the temperature changes stimulated this unusual morphogenesis. At 27° C, T. acomys was incapable of multiplying and died when cultured in fresh Schneider's Drosophila medium supplemented with 20% FCS, but co-cultivation with the mosquito cell lines or cultivation in cell-free supernatants from 1-week-old mosquito cell cultures was successful at this temperature; most of the parasites multiplied as epimastigotes.