title: Characterization of immune responses caused by bovine leukemia virus envelope peptides in sheep.
abstract: To study the immunomodulative activity caused by bovine leukemia virus envelope (BLV Env) peptide, sheep were immunized with two kinds of Th-epitope peptides, peptide 98 (BLV Env 98-117), and 61 (BLV Env 61-78). Four of eight immunized sheep showed specific proliferative responses against both of the peptide stimulations. To characterize the cells responding to the peptides, peptide-specific cells were established from the responding sheep by the continuous stimulation of peripheral blood mononuclear cells (PBMCs) with either peptide 98 or 61 in vitro. The peptide 98-specific cells consisted of CD4-positive cells, whereas the peptide 61-specific cells consisted of CD8-positive cells and MHC class II-positive cells. In addition, cytokine profile analysis indicated that the peptide 98-stimulated cells expressed IFN-gamma but not IL-10, although the peptide 61-stimulated cells expressed IL-10 but not IFN-gamma. These results show that BLV envelope peptides 98 and 61 can modulate immune responses of sheep lymphocytes in different ways and may contribute to the pathogenesis of BLV infection.
authors.affiliation: Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kabeya
authors.forename: K
authors.initials: K
authors.lastname: Ohashi
authors.forename: C
authors.initials: C
authors.lastname: Sugimoto
authors.forename: M
authors.initials: M
authors.lastname: Onuma
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002417:Cattle; D016207:Cytokines / Q000235:genetics*; D000939:Epitopes / Q000276:immunology; D015967:Gene Expression Regulation, Viral / Q000276:immunology; D015686:Gene Products, env / Q000737:chemistry / Q000276:immunology*; D001909:Leukemia Virus, Bovine / Q000276:immunology*; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics; D012756:Sheep; D014158:Transcription, Genetic
chemical_list: D016207:Cytokines; D000939:Epitopes; D015686:Gene Products, env; D010446:Peptide Fragments; D012333:RNA, Messenger