title: Generation of Leishmania donovani axenic amastigotes: their growth and biological characteristics.
abstract: In this report, we describe an in vitro culture system for the generation and propagation of axenic amastigotes from the well characterised 1S-CL2D line of Leishmania donovani. Fine structure analyses of these in vitro-grown amastigotes demonstrated that they possessed morphological features characteristic of L. donovani tissue-derived amastigotes. Further, these axenic amastigotes (LdAxAm) were shown to synthesise and release a secretory acid phosphatase isoform similar to that produced by intracellular amastigotes. Such LdAxAm also expressed surface membrane 3'-nucleotidase enzyme activity similar to that of tissue-derived amastigotes. Moreover, LdAxAm, in contrast to promastigotes, expressed significant levels of the amastigote-specific A2 proteins. In addition, LdAxAm, derived from long term cultures of Ld 1S-CL2D promastigotes, had significant infectivity for both human macrophages in vitro and for hamsters in vivo. Thus, the in vitro culture system described herein provides a useful tool for the generation of large quantities of uniform populations of axenic amastigotes of the L. donovani 1S-CL2D line. The availability of such material should greatly facilitate studies concerning the cell and molecular biology of this parasite developmental stage.
authors.affiliation: Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Bethesda, MD, USA.
authors.forename: Alain
authors.initials: A
authors.lastname: Debrabant
authors.forename: Manju B
authors.initials: MB
authors.lastname: Joshi
authors.forename: Paulo F P
authors.initials: PF
authors.lastname: Pimenta
authors.forename: Dennis M
authors.initials: DM
authors.lastname: Dwyer
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000818:Animals; D006224:Cricetinae; D006790:Host-Parasite Interactions; D006801:Humans; D007893:Leishmania donovani / Q000502:physiology* / Q000648:ultrastructure; D008264:Macrophages / Q000469:parasitology; D008855:Microscopy, Electron, Scanning; D010274:Parasitology / Q000379:methods*; D014774:Virulence
chemical_list: D000135:Acid Phosphatase