Guzmán María G, Rodríguez Rayner, Rodríguez Rosmari, Hermida Lisset, Alvarez Mayling, Lazo Laura, Muné Mayra, Rosario Delfina, Valdés Katia, Vázquez Susana, Martinez Rafael, Serrano Teresita, Paez Jorge, Espinosa Raúl, Pumariega Tania, Guillén Gerardo
Virology Department, Pan American Health Organization/World Health Organization Collaborating Center for Viral Diseases, Pedro Kourí Tropical Medicine Institute, Autopista Novia del Mediodía, Havana, Cuba.
Am J Trop Med Hyg. 2003 Aug;69(2):129-34.
A recombinant vaccine that expresses the envelope (E) gene of dengue virus type 4 was tested for immunogenicity and protection in Macaca fascicularis. One hundred micrograms of semipurified recombinant E protein (E4rec) expressed in Pichia pastoris was used to immunize three animals. Neutralizing antibodies to dengue 4 virus with a titer of 1:30 were detected in all immunized monkeys prior to challenge. Animals were challenged with 10(5) plaque-forming units of dengue 4 virus. One vaccine-immunized monkey was protected from viremia, while the other two were partially protected. Monkeys immunized with E4rec elicited the highest neutralizing antibody titers (P < 0.05) ranging from 1:85 to 1:640 at day 30. In both immunized and control animals, the longest duration of viremia correlated with earliest and highest level of IgM antibody to dengue virus. The vaccinated animals showed anamnestic antibody responses upon virus challenge, indicating successful priming by the recombinant vaccine. Our results suggest that E4rec expressed in P. pastoris can provide partial protection against viremia. However, the results were not effective enough to use it as a vaccine candidate. Further work is required to improve the quality of the immunogen.
一种表达登革4型病毒包膜（E）基因的重组疫苗在食蟹猴中进行了免疫原性和保护性测试。用100微克在毕赤酵母中表达的半纯化重组E蛋白（E4rec）免疫三只动物。在攻击前，所有免疫的猴子中均检测到效价为1:30的抗登革4病毒中和抗体。用10⁵个登革4病毒空斑形成单位攻击动物。一只接种疫苗的猴子免受病毒血症影响，而另外两只受到部分保护。用E4rec免疫的猴子在第30天产生了最高的中和抗体效价（P < 0.05），范围为1:85至1:640。在免疫动物和对照动物中，病毒血症的最长持续时间与抗登革病毒IgM抗体的最早和最高水平相关。接种疫苗的动物在病毒攻击后表现出回忆性抗体反应，表明重组疫苗引发成功。我们的结果表明，在毕赤酵母中表达的E4rec可以提供对病毒血症的部分保护。然而，结果还不足以将其用作候选疫苗。需要进一步开展工作以提高免疫原的质量。
