Immunological equivalence between mouse brain-derived and Vero cell-derived Japanese encephalitis vaccines

• Published in: Virus research Vol. 121; no. 2; pp. 152 - 160
• Main Authors: Abe, Motoharu, Shiosaki, Kouichi, Hammar, Lena, Sonoda, Kengo, Xing, Li, Kuzuhara, Syoji, Kino, Yoichiro, Cheng, R. Holland
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2006
• Subjects: Adolescent; Adult; Animals; Antibodies, Monoclonal - immunology; Antibodies, Viral - immunology; Antigens, Viral - immunology; Cell system derived whole virus vaccine; Cercopithecus aethiops; Child; Encephalitis Virus, Japanese - immunology; Encephalitis, Japanese - immunology; Encephalitis, Japanese - prevention & control; Enzyme-Linked Immunosorbent Assay; Epitopes, B-Lymphocyte - immunology; Formaldehyde; Fusion protein refolding; Humans; Japanese encephalitis; Japanese Encephalitis Vaccines - immunology; Japanese Encephalitis Vaccines - metabolism; Japanese encephalitis virus; Medicin och hälsovetenskap; Middle Aged; Neutralization Tests; Neutralizing antibodies; Vero Cells; Cell system derived whole virus vaccine; Fusion protein refolding; Neutralizing antibodies; Japanese encephalitis
• ISSN: 0168-1702; 1872-7492
• DOI: 10.1016/j.virusres.2006.05.004

The persistent spread via animal reservoirs urges expanding vaccination programs against pathogens like the Japanese encephalitis virus, JEV. The JEV is spreads to new areas by domestic as well as by wild animals. Although there is a safe and efficient vaccine on the market, this is derived from infected mouse brains, why today's situation requires overcoming the potential risk caused by using animal tissues. To meet this demand we have developed a Vero cell-derived JEV vaccine, using the same virus strain as in the established one. A phase III clinical study of the new vaccine has recently been completed with positive outcome. Like the established mouse brain-derived vaccine, the Vero cell-derived one is a formalin inactivated whole virus vaccine. We here demonstrate the very good agreement in immunological tests between the two antigens. The study includes analyses with two neutralizing monoclonal antibodies that blocks cell entry at a late stage in infection, assumedly interfering with fusion-related refolding in the virus fusion protein. It is obvious that the formalin inactivation treatment, with both virus preparations, retains these essential vaccine epitopes.