Trypanosoma (Schizotrypanum) dionisii: Influence of Mouse Peritoneal Macrophages and Calf Sera on Extracellular Growth in vitro at 37  C

Abstract

27Macrophages and certain batches of sera were essential for extracellular multiplication of Trypanosoma dionisii in vitro in medium 199 with 20 % (v/v) calf serum at 37 "C. In mixtures of ' good ' and ' bad ' batches of sera, multiplication increased as the proportion of the former was increased. Mixtures of 'bad' and 'intermediate' sera permitted virtually no growth. Phagocytosis of parasites by macrophages was unaffected by different batches of sera, though reduced in medium 199 alone. Replacement of supernatant medium by medium containing 'bad' serum reduced the macrophage infection rate no more than did transfer to medium containing 'good' serum. Daily addition of medium conditioned by prior contact with macrophages in vitro to cultures of trypanosomes without macrophages resulted in growth at least as good as that in the presence of macrophages. Extracellular replication in medium 199 at 37 "C apparently required at least two factors:'M factor' provided by macrophages, but not required at 28 " C ; and 'S + factor' present in some batches of calf serum, essential also at 28 "C but not required by intracellular parasites. Some sera appeared to contain an inhibitory ' S -factor'.

Evasion of the oxidative microbicidal activity of human monocytes by trypomastigotes ofTrypanosoma dionisii

“…Culture forms of T. dionisii (stock P2) isolated by Dr J. R. Baker from bats (Baker, 1980) were grown in liquid medium L4 NHS at 28 °C, either for 2 days for epimastigotes or for 9 days for trypomastigotes (Baker, Liston & Selden, 1976;Baker & Selden, 1978). When radioactive trypanosomes were required [5,6-3 H] uridine (0-5 mCi/20 ml) was added to the growth medium at the beginning of the growth period (Sanderson, Bunn Moreno & Lopez, 1978).…”

Trypanosoma dionisii as an experimental model to study anti-Trypanosoma cruzi drugs: A comparative analysis with benznidazole, posaconazole and amiodarone

“…We show that the use of Trypanosoma dionisii, a member of the Trypanosoma genus and Schyzotrypanum subgenus, may constitute an alternative model for drug screening and further biochemical studies on the mechanism of Chagas therapy. Since the classical studies carried out by Baker and Selden [31], bloodstream trypomastigotes have been isolated from bats and shown to infect mammalian cells in vitro. They transform into amastigote forms that proliferate within the host cells and subsequently transform back in trypomastigotes that are released into the extracellular medium and infect new cells.…”

An in vitro comparison of Trypanosoma spp. (subgenus Schizotrypanum) from bats

“…T. vespertilionis and T. dionisii did not develop in chicken fibroblasts, whereas amastigotes of T. hedrieki and T. myoti did. European workers found that T. dionisii developed better in mammalian macrophages than in fibroblasts (Baker et al, 1972a(Baker et al, , 1972bListon, 1975;Baker & Selden, 1978;Liston & Baker, 1978). More recent work (Baker et al, 1980) showed that cultured trypomastigotes of T. dionisii would also develop in 'buffalo lung cells'.…”