title: Passive immunization with anti-ActA and anti-listeriolysin O antibodies protects against Listeria monocytogenes infection in mice.
abstract: Listeria monocytogenes is an intracellular pathogen that causes listeriosis. Due to its intracellular niche, L. monocytogenes has evolved to limit immune recognition and response to infection. Antibodies that are slightly induced by listerial infection are completely unable to protect re-infection of L. monocytogenes. Thus, a role of antibody on the protective effect against L. monocytogenes infection has been neglected for a long time. In the present study, we reported that passive immunization with an excessive amount of antibodies against ActA and listeriolysin O (LLO) attenuates severity of L. monocytogenes infection. Combination of these antibodies improved survival of L. monocytogenes infected mice. Bacterial load in spleen and liver of listerial infected mice and infected RAW264.7 cells were significantly reduced by administration of anti-ActA and anti-LLO antibodies. In addition, anti-LLO antibody neutralized LLO activity and inhibited the bacterial escape from the lysosomal compartments. Moreover, anti-ActA antibody neutralized ActA activity and suppressed actin tail formation and cell-to-cell spread. Thus, our studies reveal that passive immunization with the excessive amount of anti-ActA and -LLO antibodies has potential to provide the protective effect against listerial infection.
authors.affiliation: Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.
authors.forename: Krisana
authors.initials: K
authors.lastname: Asano
authors.affiliation: Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sashinami
authors.affiliation: Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.
authors.forename: Arihiro
authors.initials: A
authors.lastname: Osanai
authors.affiliation: Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.
authors.forename: Shouhei
authors.initials: S
authors.lastname: Hirose
authors.affiliation: Laboratory of Zoonoses, Kitasato University School of Veterinary Medicine, 35-1 Higashi 23-bancho, Towada, Aomori, 034-8628, Japan.
authors.forename: Hisaya K
authors.initials: HK
authors.lastname: Ono
authors.affiliation: Institute for Animal Experimentation, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.
authors.forename: Kouji
authors.initials: K
authors.lastname: Narita
authors.affiliation: Laboratory of Zoonoses, Kitasato University School of Veterinary Medicine, 35-1 Higashi 23-bancho, Towada, Aomori, 034-8628, Japan.
authors.forename: Dong-Liang
authors.initials: DL
authors.lastname: Hu
authors.affiliation: Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Nakane
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology; D001426:Bacterial Proteins / Q000276:immunology*; D001427:Bacterial Toxins / Q000276:immunology*; D002460:Cell Line; D005260:Female; D006360:Heat-Shock Proteins / Q000276:immunology*; D006460:Hemolysin Proteins / Q000276:immunology*; D007116:Immunization, Passive; D008089:Listeria monocytogenes; D008088:Listeriosis / Q000276:immunology*; D008099:Liver / Q000382:microbiology; D008247:Lysosomes / Q000378:metabolism; D008565:Membrane Proteins / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009500:Neutralization Tests; D000067996:RAW 264.7 Cells; D013154:Spleen / Q000382:microbiology; D037521:Virulence Factors
chemical_list: D057134:Antibodies, Neutralizing; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006360:Heat-Shock Proteins; D006460:Hemolysin Proteins; D008565:Membrane Proteins; D037521:Virulence Factors; C072980:actA protein, Listeria monocytogenes; C038705:hlyA protein, Listeria monocytogenes