title: Trypsin-stimulated transformation of Trypanosoma brucei gambiense bloodstream forms to procyclic forms in vitro.
abstract: The effect of trypsin treatment on the transformation of monomorphic Trypanosoma b. gambiense (Wellcome strain) bloodstream forms to procyclic forms was studied in HEPES-buffered RPMI 1640 medium supplemented with 20% inactivated fetal calf serum in the presence of GA-1 cells as feeder layers at 27 degrees C. In this system, 35%-40% of the bloodstream forms transformed to procyclic forms within 24 h, and over 95% of the trypanosomes changed into procyclic forms by day 3 after initiation of the culture. Established cultures of procyclic forms yielded up to 1.5-2 x 10(7) trypanosomes/ml. However, transformation of nontreated and inhibited trypsin-treated bloodstream forms were prolonged compared to trypsin-treated populations. In this experiment, the first procyclic forms could be detected on day 7 after initiation of the culture and transformation was complete within 15 days. The transformation of T. b. gambiense from bloodstream to procyclic forms required the living GA-1 cells as feeder layer cells, but established cultures of procyclic forms could be maintained in the culture medium without feeder cells for more than 300 days.
authors.affiliation: Department of Medical Zoology, Nagoya City University Medical School, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yabu
authors.forename: T
authors.initials: T
authors.lastname: Takayanagi
mesh_terms: D000818:Animals; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D014347:Trypanosoma brucei gambiense / Q000187:drug effects / Q000254:growth & development* / Q000648:ultrastructure; D014357:Trypsin / Q000494:pharmacology*
chemical_list: D014357:Trypsin