title: Localization of an immunoinhibitory epitope of the cysteine proteinase, cathepsin L.
abstract: Antibodies, raised in chickens (IgY) and rabbits (IgG) against the lysosomal proteinase cathepsin L, targeted the enzyme in an ELISA and Western blot. In contrast to the rabbit IgG, the chicken IgY was immunoinhibitory towards cathepsin L. An epitope that elicits immunoinhibitory antibodies has been localized to an active site-associated peptide sequence. The corresponding free peptide, coated down in an ELISA, is recognised by the chicken IgY, but not the rabbit IgG. This peptide was able to inhibit the immunoinhibition of cathepsin L by chicken anti-cathepsin L IgY, suggesting its complete or partial identity with an immunogenic epitope for chickens in whole cathepsin L.
authors.affiliation: Department of Biochemistry, University of Natal, South Africa.
authors.forename: T H
authors.initials: TH
authors.lastname: Coetzer
authors.forename: R N
authors.initials: RN
authors.lastname: Pike
authors.forename: C
authors.initials: C
authors.lastname: Dennison
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D001665:Binding Sites; D056668:Cathepsin L; D002403:Cathepsins / Q000037:antagonists & inhibitors / Q000276:immunology*; D002645:Chickens; D003546:Cysteine Endopeptidases / Q000276:immunology*; D010450:Endopeptidases; D000939:Epitopes / Q000302:isolation & purification; D007074:Immunoglobulin G; D007136:Immunoglobulins; D010455:Peptides / Q000276:immunology; D011817:Rabbits; D012756:Sheep
chemical_list: D000939:Epitopes; C016512:IgY; D007074:Immunoglobulin G; D007136:Immunoglobulins; D010455:Peptides; D002403:Cathepsins; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; D056668:Cathepsin L