title: Suppression of murine lymphocyte proliferation induced by a small RNA purified from the Taenia solium metacestode.
abstract: A substance from Taenia solium metacestodes that decreases lymphocyte proliferation induced by concanavalin A was isolated. The molecular weight of this substance was estimated to be slightly more than 1,450 Da. Crude metacestode factor was fractionated through a Bio-gel P-6 column. Peak 1 showed suppressive activity. After incubation with RNase the substance lost its activity. Incubation of this material with trypsin or papain increased its suppressive activity. It was stable at boiling temperature for 10 min. The incubation of this substance with murine macrophages had no effect on [3H]-thymidine uptake by cocultured fresh splenic lymphocytes stimulated with concanavalin A. Conversely, cocultures of lymphocytes pretreated with the substance and fresh splenic lymphocytes showed a decreased incorporation of [3H]-thymidine. These results suggest that this substance is a RNA-peptide molecule whose RNA moiety accounts for its suppressive activity. The findings also suggest that in vivo the factor may be a modulator of the immune response.
authors.affiliation: Departamento de Microbiología e Inmunología, Universidad Nacional Autonóma de México, México, D.F.
authors.forename: P
authors.initials: P
authors.lastname: Tato
authors.forename: A M
authors.initials: AM
authors.lastname: Castro
authors.forename: D
authors.initials: D
authors.lastname: Rodríguez
authors.forename: R
authors.initials: R
authors.lastname: Soto
authors.forename: F
authors.initials: F
authors.lastname: Arechavaleta
authors.forename: J L
authors.initials: JL
authors.lastname: Molinari
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006131:Growth Inhibitors / Q000737:chemistry*; D006358:Hot Temperature; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010206:Papain / Q000494:pharmacology; D010446:Peptide Fragments / Q000737:chemistry / Q000276:immunology; D018510:RNA, Helminth / Q000737:chemistry*; D012260:Ribonucleases / Q000494:pharmacology; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology; D013621:Taenia / Q000737:chemistry*; D014357:Trypsin / Q000494:pharmacology
chemical_list: D006131:Growth Inhibitors; D010446:Peptide Fragments; D018510:RNA, Helminth; D012260:Ribonucleases; D014357:Trypsin; D010206:Papain