Protection of mice from inhaled ricin by vaccination with ricin or by passive treatment with heterologous antibody

• Published in: Vaccine Vol. 11; no. 7; pp. 743 - 746
• Main Authors: Hewetson, John F., Rivera, Victor R., Creasia, Donald A., Lemley, Paul V., Rippy, Marian K., Poli, Mark A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1993; Elsevier
• Subjects: Aerosols; Analysis of the immune response. Humoral and cellular immunity; Animals; antibody; Antibody production; Biological and medical sciences; Enzyme-Linked Immunosorbent Assay; Freund's Adjuvant; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Immunization, Passive; Immunobiology; inhalation; Mice; protection; Ricin; Ricin - immunology; Ricin - toxicity; Vaccination; inhalation; protection; antibody; Ricin; vaccination; Performance evaluation; Immunoprotection; Immune response; Vaccination; Rodentia; Passive immunity; Blocking antibody; Vertebrata; Mammalia; Castor (seed); Treatment; Mouse; Immunotherapy; Humoral immunity
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/0264-410X(93)90259-Z

Mice were vaccinated subcutaneously with 25 μg kg −1 of ricin in the presence of Freund's complete adjuvant or Ribi™ adjuvant, followed by a boost 14 days later with 50 μg kg −1 ricin in Freund's incomplete adjuvant or Ribi adjuvant, respectively. Three subsequent boosts at 28-day intervals with 25 μg kg −1 ricin yielded high anti-ricin antibody titres as determined by ELISA. Vaccinated animals were exposed to an aerosolized LD 99 dose of ricin. With the exception of one death not attributable to ricin intoxication, all vaccinated mice survived the lethal aerosol exposure. In addition, a passive protection regimen was evaluated in mice pretreated with 100 μg purified goat anti-ricin IgG administered intravenously, and then challenged with ricin intravenously. All were resistant to 125 μg kg −1 of ricin, a dose greater than 25 times the intravenous lethal dose. Mice injected intravenously with 5 mg of the same IgG were protected from a lethal aerosol challenge. These results indicated that it is possible to protect animals from inhaled ricin by vaccination or passive administration of specific antibodies.