title: Microbicidal power of alpha radiation in sterilizing germinating Bacillus anthracis spores.
abstract: Radioimmunotherapy (RIT) takes advantage of the specificity and affinity of the antigen-antibody interaction to deliver microbicidal radioactive nuclides to a site of infection. In this study, we investigated the microbicidal properties of an alpha particle-emitting 213Bi-labeled monoclonal antibody (MAb), EA2-1 (213Bi-EA2-1), that binds to the immunodominant antigen on Bacillus anthracis spores. Our results showed that dormant spores were resistant to 213Bi-EA2-1. Significant spore killing was observed following treatment with EA2-1 labeled with 300 μCi 213Bi; however, this effect was not dependent on the MAb. In contrast, when spores were germinating, 213Bi-EA2-1 mediated MAb-specific killing in a dose-dependent manner. Dormant spores are very resistant to RIT, and RIT should focus on targeting vegetative cells and germinating spores.
authors.affiliation: Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA.
authors.forename: Johanna
authors.initials: J
authors.lastname: Rivera
authors.forename: Alfred
authors.initials: A
authors.lastname: Morgenstern
authors.forename: Frank
authors.initials: F
authors.lastname: Bruchertseifer
authors.forename: John F
authors.initials: JF
authors.lastname: Kearney
authors.forename: Charles L
authors.initials: CL
authors.lastname: Turnbough
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Dadachova
authors.forename: Arturo
authors.initials: A
authors.lastname: Casadevall
mesh_terms: D000512:Alpha Particles / Q000627:therapeutic use*; D000911:Antibodies, Monoclonal; D001408:Bacillus anthracis / Q000528:radiation effects*; D001729:Bismuth; D008858:Microscopy, Phase-Contrast; D011868:Radioisotopes; D013171:Spores, Bacterial / Q000528:radiation effects*
chemical_list: D000911:Antibodies, Monoclonal; D011868:Radioisotopes; D001729:Bismuth