title: Comparison of the peptidase activity in the oncosphere excretory/secretory products of Taenia solium and Taenia saginata.
abstract: We compared the peptidase activities of the excretory/secretory (E/S) antigens of oncospheres of Taenia solium and related, but nonpathogenic, Taenia saginata. Taenia solium and T. saginata oncospheres were cultured, and the spent media of 24-, 48-, 72-, and 96-hr fractions were analyzed. Activities for serine peptidases (chymotrypsin-, trypsin-, and elastase-like), cysteine peptidases (cathepsin B-, cathepsin L-, and calpaine-like), and aminopeptidase (B-like peptidases) were tested fluorometrically with peptides coupled to 7-amino-4-methylcoumarin. In both species, the E/S antigens showed cysteine, serine, and aminopeptidase activities. Although no particular peptidase had high activity in T. solium, and was absent in T. saginata, or vice versa, different patterns of activity were found. A chymotrypsin-like peptidase showed the highest activity in both parasites, and it had 10 times higher activity in T. solium than in T. saginata. Trypsin-like and cathepsin B-like activities were significantly higher in T. solium. Minimal levels of cathepsin B were present in both species, and higher levels of elastase-like and cathepsin L-like activity were observed in T. saginata. Taenia solium and T. saginata have different levels and temporal activities of proteolytic enzymes that could play a modulator role in the host specificity for larval invasion through penetration of the intestinal mucosa.
authors.affiliation: Laboratorios de Investigación y Desarrollo, Facultad de Ciencias, Universidad Peruana Cayetano Heredia, Av. Honorio Delgado 430, SMP, Lima, Perú.
authors.forename: Mirko J
authors.initials: MJ
authors.lastname: Zimic
authors.forename: Jesús
authors.initials: J
authors.lastname: Infantes
authors.forename: César
authors.initials: C
authors.lastname: López
authors.forename: Jeanette
authors.initials: J
authors.lastname: Velásquez
authors.forename: Marilú
authors.initials: M
authors.lastname: Farfán
authors.forename: Mónica
authors.initials: M
authors.lastname: Pajuelo
authors.forename: Patricia
authors.initials: P
authors.lastname: Sheen
authors.forename: Manuela
authors.initials: M
authors.lastname: Verastegui
authors.forename: Armando
authors.initials: A
authors.lastname: Gonzalez
authors.forename: Hector H
authors.initials: HH
authors.lastname: Garciá
authors.forename: Robert H
authors.initials: RH
authors.lastname: Gilman
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology / Q000378:metabolism; D002918:Chymotrypsin / Q000276:immunology / Q000378:metabolism; D004789:Enzyme Activation; D006801:Humans; D010194:Pancreatin / Q000378:metabolism; D010447:Peptide Hydrolases / Q000276:immunology / Q000378:metabolism*; D013379:Substrate Specificity; D041202:Taenia saginata / Q000201:enzymology* / Q000276:immunology / Q000502:physiology; D041201:Taenia solium / Q000201:enzymology* / Q000276:immunology / Q000502:physiology; D013622:Taeniasis / Q000469:parasitology
chemical_list: D000947:Antigens, Helminth; D010194:Pancreatin; D010447:Peptide Hydrolases; D002918:Chymotrypsin