title: Therapy of murine pulmonary aspergillosis with antibody-alliinase conjugates and alliin.
abstract: Aspergillus fumigatus is an opportunistic fungal pathogen responsible for invasive aspergillosis in immunocompromised individuals. The high morbidity and mortality rates as well as the poor efficacy of antifungal agents remain major clinical concerns. Allicin (diallyl-dithiosulfinate), which is produced by the garlic enzyme alliinase from the harmless substrate alliin, has been shown to have wide-range antifungal specificity. A monoclonal antibody (MAb) against A. fumigatus was produced and chemically ligated to the enzyme alliinase. The purified antibody-alliinase conjugate bound to conidia and hyphae of A. fumigatus at nanomolar concentrations. In the presence of alliin, the conjugate produced cytotoxic allicin molecules, which killed the fungus. In vivo testing of the therapeutical potential of the conjugate was carried out in immunosuppressed mice infected intranasally with conidia of A. fumigatus. Intratracheal (i.t.) instillation of the conjugate and alliin (four treatments) resulted in 80 to 85% animal survival (36 days), with almost complete fungal clearance. Repetitive intratracheal administration of the conjugate and alliin was also effective when treatments were initiated at a more advanced stage of infection (50 h). The fungi were killed specifically without causing damage to the lung tissue or overt discomfort to the animals. Intratracheal instillation of the conjugate without alliin or of the unconjugated monoclonal antibody significantly delayed the death of the infected mice, but only 20% of the animals survived. A limitation of this study is that the demonstration was achieved in a constrained setting. Other routes of drug delivery will be investigated for the treatment of pulmonary and extrapulmonary aspergillosis.
authors: Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
authors: Elena
authors: E
authors: Appel
authors: Alexandra
authors: A
authors: Vallon-Eberhard
authors: Aharon
authors: A
authors: Rabinkov
authors: Ori
authors: O
authors: Brenner
authors: Irina
authors: I
authors: Shin
authors: Keren
authors: K
authors: Sasson
authors: Yona
authors: Y
authors: Shadkchan
authors: Nir
authors: N
authors: Osherov
authors: Steffen
authors: S
authors: Jung
authors: David
authors: D
authors: Mirelman
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry*; D000935:Antifungal Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D001232:Aspergillus fumigatus / Q000187:drug effects / Q000502:physiology; D013437:Carbon-Sulfur Lyases / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D016867:Immunocompromised Host; D053208:Kaplan-Meier Estimate; D051379:Mice; D008813:Mice, Inbred ICR; D055732:Pulmonary Aspergillosis / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality
chemical_list: D000911:Antibodies, Monoclonal; D000935:Antifungal Agents; D013437:Carbon-Sulfur Lyases; C019243:alliin lyase