title: LC16m8, a highly attenuated vaccinia virus vaccine lacking expression of the membrane protein B5R, protects monkeys from monkeypox.
abstract: The potential threat of smallpox as a bioweapon has led to the production and stockpiling of smallpox vaccine in some countries. Human monkeypox, a rare but important viral zoonosis endemic to central and western Africa, has recently emerged in the United States. Thus, even though smallpox has been eradicated, a vaccinia virus vaccine that can induce protective immunity against smallpox and monkeypox is still invaluable. The ability of the highly attenuated vaccinia virus vaccine strain LC16m8, with a mutation in the important immunogenic membrane protein B5R, to induce protective immunity against monkeypox in nonhuman primates was evaluated in comparison with the parental Lister strain. Monkeys were immunized with LC16m8 or Lister and then infected intranasally or subcutaneously with monkeypox virus strain Liberia or Zr-599, respectively. Immunized monkeys showed no symptoms of monkeypox in the intranasal-inoculation model, while nonimmunized controls showed typical symptoms. In the subcutaneous-inoculation model, monkeys immunized with LC16m8 showed no symptoms of monkeypox except for a mild ulcer at the site of monkeypox virus inoculation, and those immunized with Lister showed no symptoms of monkeypox, while nonimmunized controls showed lethal and typical symptoms. These results indicate that LC16m8 prevents lethal monkeypox in monkeys, and they suggest that LC16m8 may induce protective immunity against smallpox.
authors.affiliation: Special Pathogens Laboratory, Department of Virology 1, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan. msaijo@nih.go.jp
authors.forename: Masayuki
authors.initials: M
authors.lastname: Saijo
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ami
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Suzaki
authors.forename: Noriyo
authors.initials: N
authors.lastname: Nagata
authors.forename: Naoko
authors.initials: N
authors.lastname: Iwata
authors.forename: Hideki
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Momoko
authors.initials: M
authors.lastname: Ogata
authors.forename: Shuetsu
authors.initials: S
authors.lastname: Fukushi
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Mizutani
authors.forename: Tetsutaro
authors.initials: T
authors.lastname: Sata
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kurata
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kurane
authors.forename: Shigeru
authors.initials: S
authors.lastname: Morikawa
mesh_terms: D000818:Animals; D000882:Haplorhini; D008562:Membrane Glycoproteins / Q000276:immunology; D045908:Mpox, Monkeypox / Q000517:prevention & control*; D008993:Monkeypox virus / Q000187:drug effects*; D012900:Smallpox Vaccine / Q000008:administration & dosage* / Q000276:immunology; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000276:immunology; D014616:Vaccinia virus / Q000276:immunology*; D014759:Viral Envelope Proteins / Q000276:immunology
chemical_list: D008562:Membrane Glycoproteins; D012900:Smallpox Vaccine; D014613:Vaccines, Attenuated; D014759:Viral Envelope Proteins; C074512:42kDa protein, Vaccinia virus