title: Babesia bovis: effects of cysteine protease inhibitors on in vitro growth.
abstract: In the present study, we examined the effects of four kinds of cysteine protease inhibitors (E64, E64d, leupeptin, and ALLN) on the in vitro asexual growth of Babesia bovis. Of these, only the lipophilic inhibitors, E64d and ALLN, were found to effectively inhibit the growth of B. bovis. In further experiments, E64d, but not ALLN, significantly suppressed the parasite's invasion of host erythrocytes, while both chemicals, especially ALLN, inhibited the parasite's replication within the infected erythrocytes. These data suggested the presence of cysteine protease(s) derived from B. bovis, in which the protease(s) would play important roles in the erythrocyte invasion and/or replication processes of the parasite.
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Okubo
authors.forename: Naoaki
authors.initials: N
authors.lastname: Yokoyama
authors.forename: Yadav
authors.initials: Y
authors.lastname: Govind
authors.forename: Andy
authors.initials: A
authors.lastname: Alhassan
authors.forename: Ikuo
authors.initials: I
authors.lastname: Igarashi
mesh_terms: D000818:Animals; D016793:Babesia bovis / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development; D003546:Cysteine Endopeptidases / Q000502:physiology; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology*; D004912:Erythrocytes / Q000469:parasitology; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D007976:Leupeptins / Q000494:pharmacology
chemical_list: D015853:Cysteine Proteinase Inhibitors; D007976:Leupeptins; C063261:acetylleucyl-leucyl-norleucinal; D003546:Cysteine Endopeptidases; D007930:Leucine; C032854:leupeptin; C108192:aloxistatin; C024974:E 64