Comparative positions of kinetoplasts in Trypanosoma musculi and Trypanosoma lewisi during development in vitro

Abstract

The development of Trypanosoma musculi and Trypanosoma lewisi were studied in vitro in the presence of adherent splenic cells. Both parasites developed only when attached by their flagellar tips to adherent splenic cells. During the proliferation of T. musculi, the kinetoplast migrated towards the nucleus, and once in the vicinity of the nucleus, the nuclear division was triggered. The kinetoplast of T. lewisi did not migrate towards the nucleus, but remained at its original location. The nucleus and kinetoplast divided at the same time in both parasites, and parasites started dividing from their flagellar ends and T. musculi and T. lewisi daughter cells were formed within 48 h. The unavailability of the adherent splenic cells in vitro led the parasites to transform into round/oval nonviable forms.

Cell cycle and cleavage events during in vitro cultivation of bloodstream forms of Trypanosoma lewisi, a zoonotic pathogen

“…Epimastigote stages with multiple divisions forming rosette shaped structures were described in early studies [13,16,17], while the expected proliferation in trypomastigotes was rarely observed and it was suggested that they may require transformation to epimastigotes [1]. In a later study, proliferation of trypomastigotes was observed when it was cultured in vitro [18]. However, detailed information regarding the cell cycle events was not provided.…”

“…Several investigators have cultured Herpetosoma trypanosomes in association with various mammalian cell lines [12][13][14][15]. In the early studies, T. lewisi had been maintained continuously [11] and morphological polymorphism was observed during in vitro cultivation [16][17][18]. However, there has been no systematic analysis, to date, that resolves these morphological cell types and relates them to the corresponding cell cycle events.…”