title: In vitro stimulation of metacyclogenesis in Leishmania braziliensis, L. donovani, L. major and L. mexicana.
abstract: Promastigotes of Leishmania braziliensis, L. donovani, L. major and L. mexicana recently derived from tissue amastigotes were cultured in Schneider's Drosophila medium supplemented with 20% (v/v) heat-inactivated foetal calf serum and 25 micrograms gentamicin sulfate/ml at pH 5.5. These cultures produced more metacyclic promastigotes in their stationary-phase populations than others cultured at pH 7.0. Metacyclic promastigotes possessed a short (< or = 8 microns) and narrow (< or = 1.5 microns) cell body with a flagellum twice or more the length of the cell body. Promastigotes from acidic cultures were more resistant to complement-mediated lysis and more infective in vivo than those grown at neutral pH. These results demonstrate that induction of metacyclogenesis by acidic pH is a response conserved across a variety of species of Leishmania.
authors.affiliation: Liverpool School of Tropical Medicine.
authors.forename: H A
authors.initials: HA
authors.lastname: Zakai
authors.forename: M L
authors.initials: ML
authors.lastname: Chance
authors.forename: P A
authors.initials: PA
authors.lastname: Bates
mesh_terms: D000818:Animals; D003165:Complement System Proteins / Q000276:immunology; D006224:Cricetinae; D006790:Host-Parasite Interactions; D006863:Hydrogen-Ion Concentration; D007891:Leishmania / Q000166:cytology / Q000254:growth & development* / Q000276:immunology / Q000472:pathogenicity; D007892:Leishmania braziliensis / Q000254:growth & development; D007893:Leishmania donovani / Q000254:growth & development; D018320:Leishmania major / Q000254:growth & development; D007894:Leishmania mexicana / Q000254:growth & development; D016773:Leishmaniasis, Cutaneous / Q000469:parasitology; D007898:Leishmaniasis, Visceral / Q000469:parasitology; D008018:Life Cycle Stages; D051379:Mice; D008807:Mice, Inbred BALB C; D013045:Species Specificity
chemical_list: D003165:Complement System Proteins