title: The use of electroblotted antigens of Trichostrongylus colubriformis to induce proliferative responses in sensitized lymphocytes from sheep.
abstract: Merino sheep were immunized against the intestinal nematode, T. colubriformis, by repeated infections, and proliferative responses of their peripheral blood lymphocytes (PBL) against parasite extracts and excretory-secretory (ES) antigens were monitored over 130 days. Maximal responses occurred 7-14 days after challenge. The ability of soluble proteins and parasite antigens to induce proliferation was compared with that of antigen-bearing particles obtained after antigen was adsorbed onto nitrocellulose. Blank particles increased c.p.m. two- to three-fold above that obtained in medium alone, and to elicit proliferative responses of comparable magnitude between 10 and 100 times more antigen was required when antigen-bearing particles were used instead of soluble extracts or defined proteins. Blood leucocytes as well as T-cell lines established by stimulation with parasite antigens in vitro reacted to moieties of from 5000 to 38,000 mol. wt in ES antigens on nitrocellulose particles. Direct comparisons of T-lymphocyte responses with antibody responses as assessed by immunoblots revealed different profiles of immunogenicity among ES proteins within individual sheep, but the 10,000, 30,000 and 75,000-90,000 mol. wt proteins were immunodominant. These proteins were also those consistently recognized by T-lymphocytes and sera from sheep immunized with ES proteins in adjuvant. Thus, this technique can be applied to identify parasite material which is immunogenic for T-lymphocytes, but the sensitivity of the procedure in sheep is less than reported in human studies.
authors.affiliation: CSIRO Division of Animal Health, McMaster Laboratory, Glebe, New South Wales, Australia.
authors.forename: D L
authors.initials: DL
authors.lastname: Emery
authors.forename: T
authors.initials: T
authors.lastname: Bendixsen
authors.forename: S J
authors.initials: SJ
authors.lastname: McClure
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology*; D015151:Immunoblotting; D008213:Lymphocyte Activation; D012756:Sheep; D012757:Sheep Diseases / Q000276:immunology*; D014253:Trichostrongylosis / Q000276:immunology / Q000662:veterinary*
chemical_list: D000947:Antigens, Helminth