Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, 430064, China.
Hubei Provincial Key Laboratory of Animal Pathogenic Microbiology, Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Wuhan, 430064, China.
Arch Virol. 2023 Jul 7;168(8):203. doi: 10.1007/s00705-023-05832-4.
The hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) is a multifunctional protein with receptor recognition ability that plays an important role in the infection of cells by NDV. An alignment of NDV HN protein sequences of different genotypes showed that vaccine strains of NDV, such as the LaSota strain, generally have an HN protein of 577 amino acids. In comparison, the HN protein of the V4 strain has 616 amino acids, with 39 more amino acids at the C-terminus. In this study, we generated a recombinant NDV (rNDV) with a 39-amino-acid truncation at the HN C-terminus based on the full-length cDNA clone of the V4 strain. This rNDV, named rV4-HN-tr, displayed thermostability similar to that of the parental V4 strain. However, growth kinetics and pathogenicity analysis suggested that rV4-HN-tr is more virulent than the V4 strain. Notably, the C-terminus of HN affected the ability of the virus to adsorb onto cells. Structural predictions further suggested that the C-terminus of HN may obstruct the sialic acid binding site. Immunization of chickens with rV4-HN-tr induced a 3.5-fold higher level of NDV-specific antibodies than that obtained with the V4 strain and provided 100% immune protection against NDV challenge. Our study suggests that rV4-HN-tr is a thermostable, safe, and highly efficient vaccine candidate against Newcastle disease.
新城疫病毒（NDV）的血凝素-神经氨酸酶（HN）蛋白是一种具有受体识别能力的多功能蛋白，在 NDV 感染细胞中发挥重要作用。不同基因型的 NDV HN 蛋白序列比对表明，NDV 的疫苗株，如 LaSota 株，通常具有 577 个氨基酸的 HN 蛋白。相比之下，V4 株的 HN 蛋白有 616 个氨基酸，C 末端多了 39 个氨基酸。在本研究中，我们基于 V4 株全长 cDNA 克隆，构建了一个 HN C 末端缺失 39 个氨基酸的重组 NDV（rNDV）。该 rNDV 命名为 rV4-HN-tr，其热稳定性与亲本 V4 株相似。然而，生长动力学和致病性分析表明，rV4-HN-tr 比 V4 株更具毒力。值得注意的是，HN 的 C 末端影响病毒吸附到细胞上的能力。结构预测进一步表明，HN 的 C 末端可能阻碍唾液酸结合位点。用 rV4-HN-tr 免疫鸡可诱导比 V4 株高 3.5 倍的 NDV 特异性抗体，对 NDV 攻毒提供 100%的免疫保护。我们的研究表明，rV4-HN-tr 是一种耐热、安全、高效的新城疫疫苗候选株。
