PDF(Pubmed)
Abstract：
Newcastle disease (ND) remains a critical disease affecting poultry in sub-Saharan Africa. In some countries, repeated outbreaks have a major impact on local economies and food security. Recently, we developed an adenovirus-vectored vaccine encoding the Fusion protein from an Ethiopian isolate of Newcastle disease virus (NDV). The adenoviral vector was designed, and a manufacturing process was developed in the context of the Livestock Vaccine Innovation Fund initiative funded by the International Development Research Centre (IDRC) of Canada. The industrially relevant recombinant vaccine technology platform is being transferred to the National Veterinary Institute (Ethiopia) for veterinary applications. Here, a manufacturing process using HEK293SF suspension cells cultured in stirred-tank bioreactors for the vaccine production is proposed. Taking into consideration supply chain limitations, options for serum-free media selection were evaluated. A streamlined downstream process including a filtration, an ultrafiltration, and a concentration step was developed. With high volumetric yields (infectious titers up to 5 × 109 TCID50/mL) in the culture supernatant, the final formulations were prepared at 1010 TCID50/mL, either in liquid or lyophilized forms. The liquid formulation was suitable and safe for mucosal vaccination and was stable for 1 week at 37 °C. Both the liquid and lyophilized formulations were stable after 6 months of storage at 4 °C. We demonstrate that the instillation of the adenoviral vector through the nasal cavity can confer protection to chickens against a lethal challenge with NDV. Overall, a manufacturing process for the adenovirus-vectored vaccine was developed, and protective doses were determined using a convenient route of delivery. Formulation and storage conditions were established, and quality control protocols were implemented.
摘要：
新城疫（ND）仍然是影响撒哈拉以南非洲地区家禽的危重疾病。在一些国家,反复爆发对当地经济和粮食安全产生重大影响。最近,我们从新城疫病毒（NDV）的埃塞俄比亚分离株中开发了编码融合蛋白的腺病毒载体疫苗。设计了腺病毒载体，在加拿大国际发展研究中心（IDRC）资助的家畜疫苗创新基金倡议的背景下开发了制造工艺。工业相关的重组疫苗技术平台正在转移到国家兽医研究所（埃塞俄比亚）用于兽医应用。这里,提出了一种使用在搅拌罐生物反应器中培养的HEK293SF悬浮细胞用于疫苗生产的制造方法。考虑到供应链的局限性，评估了无血清培养基选择的选择.流线型的下游过程，包括过滤，超滤，并开发了浓缩步骤。培养上清液中的高体积产量（感染滴度高达5×109TCID50/mL），最终制剂以1010TCID50/mL制备，液体或冻干形式。该液体制剂适合并安全用于粘膜疫苗接种，并且在37°C下稳定1周。液体和冻干制剂在4°C储存6个月后都是稳定的。我们证明，通过鼻腔滴注腺病毒载体可以保护鸡免受NDV的致命攻击。总的来说,开发了腺病毒载体疫苗的生产工艺，使用方便的递送途径确定保护剂量。建立配方和储存条件，并实施质量控制方案。
