Fraiha Ana Luiza Soares, da Silva Santos Beatriz Senra Álvares, Aguilar Nágila Rocha, Gallinari Grazielle Cossenzo, de Mendonça Angelo Ana Luiza Pessoa, Costa Julia Machado Caetano, Correia Paula Angélica, Faustino Lídia Paula, de Souza Silva Thaís Bárbara, Guedes Roberto Maurício Carvalho, Guedes Maria Isabel Maldonado Coelho, de Magalhães Vieira Machado Alexandre, Costa Erica Azevedo, Lobato Zélia Inês Portela
Department of Preventive Veterinary Medicine, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Instituto de Pesquisa René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, MG, Brazil.
Vaccine. 2025 Jan 25;45:126638. doi: 10.1016/j.vaccine.2024.126638. Epub 2024 Dec 22.
In Brazil, at least four lineages of influenza A virus circulate pig population: 2009 H1N1 flu pandemic (pH1N1), human-seasonal origin H3N2, H1N1 and H1N2 (huH1 lineages) viruses. Studies related to the occurrence of swine influenza A virus (SIAV) in Brazilian herds have been detecting an increase of occurrence of huH1 lineages. This study aimed to construct recombinant vaccines against the huH1N1 virus and test the immunogens in a murine model. The virus was constructed by reverse genetics using plasmids encoding the HA and NA sequences from a wild huH1N1 virus isolated from an infected pig. Amplified virus was inactivated, and oil-in-water (OW) and gel polymer (GP) adjuvants were used to formulate the vaccines. C57Bl6 mice received two doses with 3 weeks interval by the intramuscular route. Animals were randomly divided into 8 groups (G1-G8): G1 received OW vaccine and G2 PBS plus OW adjuvant; G3 received GP vaccine and G4 PBS plus GP adjuvant; G5 received the live virus by the intranasal route while G6 only PBS; G7 and G8 did not receive any treatment. Serum samples were collected before vaccination and after the first and second dose. Except for G8, three weeks post boost animals were challenged with a wild huH1N1 virus and observed for weight changes. After infection, bronchoalveolar lavage fluid (BALF) and lungs were collected from animals of each group for viral titers and immunohistochemistry (IHC) analysis, respectively. After booster, vaccinated groups seroconverted and the vaccines induced protection upon challenge. Reverse Genetics technique can be used to produce new and quickly updated swine influenza vaccines which is promising to control the virus in Brazilian herds. Future studies may focus on using the technology to produce multivalent recombinant vaccines against distinct strains of SIAVs circulating in Brazilian pig herds.
在巴西，至少有四种甲型流感病毒谱系在猪群中传播：2009年甲型H1N1流感大流行病毒（pH1N1）、源自人类季节性流感的H3N2、H1N1和H1N2（huH1谱系）病毒。有关巴西猪群中甲型流感病毒（SIAV）发生情况的研究一直在检测到huH1谱系的发生率有所增加。本研究旨在构建针对huH1N1病毒的重组疫苗，并在小鼠模型中测试免疫原。该病毒是通过反向遗传学使用编码从感染猪分离的野生huH1N1病毒的HA和NA序列的质粒构建的。扩增的病毒被灭活，并使用水包油（OW）和凝胶聚合物（GP）佐剂来配制疫苗。C57Bl6小鼠通过肌肉注射途径每隔3周接受两剂疫苗。动物被随机分为8组（G1 - G8）：G1接受OW疫苗，G2接受PBS加OW佐剂；G3接受GP疫苗，G4接受PBS加GP佐剂；G5通过鼻内途径接受活病毒，而G6仅接受PBS；G7和G8未接受任何处理。在接种疫苗前以及第一剂和第二剂后采集血清样本。除G8外，加强免疫后3周，用野生huH1N1病毒对动物进行攻毒，并观察体重变化。感染后，从每组动物中分别收集支气管肺泡灌洗液（BALF）和肺组织用于病毒滴度和免疫组织化学（IHC）分析。加强免疫后，接种疫苗的组出现血清转化，且疫苗在攻毒时诱导了保护作用。反向遗传学技术可用于生产新的、快速更新的猪流感疫苗，有望在巴西猪群中控制该病毒。未来的研究可能集中于利用该技术生产针对在巴西猪群中传播的不同SIAV毒株的多价重组疫苗。
