Ashraf, M.; Nesbitt, R. A.; Lee, C.* M.*: Positioning of Kinetoplasts in Trypanosoma musculi and Trypanosoma lewisi During the Development in-vitro

ABSTRACT: Trypanosoma musculi is parasitic to mice and Trypanosoma lewisi is parasitic to rats, and both of these parasites are highly specific to their hosts. 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 splenic 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. Trypanosoma musculi divided as epimastigotes. 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. Both parasites started dividing from their flagellar ends and T. musculi and T. lewisi daughter cells were formed within 48 hour. Trypanosoma lewisi did not form rosette-like pattern around the adherent cells and remained as trypomastigote forms. It is also observed that after 48 hour in culture, T. lewisi were able to divide without attaching to the adherent cells. However, the unavailability of the adherent splenic cells in vitro led the parasites to transform into round nonviable forms.