title: Liposome immune lysis assay (LILA) for gelonin.
abstract: A complement-mediated liposome immune lysis assay using entrapped calcein was developed for a plant toxin gelonin. Gelonin was covalently coupled to DPPE, and then adsorbed on to the surface of liposomes. Such antigen-bearing liposomes when incubated with anti-gelonin antibody in the presence of guinea pig complement undergo lysis. The detection range is from 3 ng to 60 ng. The method was used to monitor isolation of gelonin by affinity chromatography. It was observed that a minor peak in addition to the major one comes with gelonin, shared common epitopes/epitope with gelonin in immunological reaction. This was further confirmed by SDS-gel electrophoresis indicating the former being an isoform of gelonin. A comparative study of the immunocross-reactivity of ricin and ricin A chain with anti-gelonin antibody was carried out. It was found that while ricin A chain cross-reacted extensively with gelonin antibody and intact ricin elicited little or no cross-reactivity. It is suggested that the present LILA may be employed for the detection and quantitation of ricin A chain by this LILA method.
authors.affiliation: Department of Biochemistry, University of Delhi, India.
authors.forename: A
authors.initials: A
authors.lastname: Paul
authors.forename: S
authors.initials: S
authors.lastname: Madan
authors.forename: V M
authors.initials: VM
authors.lastname: Vasandani
authors.forename: P C
authors.initials: PC
authors.lastname: Ghosh
authors.forename: B K
authors.initials: BK
authors.lastname: Bachhawat
mesh_terms: D001667:Binding, Competitive; D015153:Blotting, Western; D003429:Cross Reactions; D003601:Cytotoxicity Tests, Immunologic / Q000379:methods*; D005452:Fluoresceins; D005779:Immunodiffusion; D007202:Indicators and Reagents; D008081:Liposomes; D010940:Plant Proteins / Q000032:analysis* / Q000276:immunology; D011500:Protein Synthesis Inhibitors / Q000032:analysis*; D054789:Ribosome Inactivating Proteins, Type 1; D012276:Ricin / Q000276:immunology; D012680:Sensitivity and Specificity
chemical_list: D005452:Fluoresceins; D007202:Indicators and Reagents; D008081:Liposomes; D010940:Plant Proteins; D011500:Protein Synthesis Inhibitors; D054789:Ribosome Inactivating Proteins, Type 1; C025674:GEL protein, Gelonium multiflorum; D012276:Ricin; C007740:fluorexon