Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Shanghai, China; Quantitative Veterinary Epidemiology, Animal Sciences Group, Wageningen University & Research, the Netherlands.
Shanghai Veterinary Research Institute, Chinese Academy of Agriculture Sciences, Shanghai, China.
Vet Immunol Immunopathol. 2023 May;259:110590. doi: 10.1016/j.vetimm.2023.110590. Epub 2023 Mar 23.
Maternal-derived antibodies (MDAs) are one of reasons why vaccination with the H9N2 inactivated whole virus (IWV) vaccine failed in poultry. Unmethylated CpG motif-containing oligodeoxynucleotides (CpG ODN) shows great potential to overcome MDAs interference in mammals, but whether it has similar characteristics in poultry is still unknown. In the present study, different classes and various copies of CpG ODN motifs were cloned into two different plasmids (pCDNA3.1 or T vector). Immunomodulatory activities and immunoadjuvant efficacy of these CpG ODN plasmids were tested in vitro and in vivo in the presence of passively transferred antibodies (PTAs) that were used to mimic MDAs. Results showed that the T vector enriched with 30 copies of CpG-A ODN and 20 copies of CpG-B ODN (T-CpG-AB) significantly up-regulated mRNA expression of chicken-interferon-α (ch-IFN-α), chicken-interferon-β (ch-IFN-β) and chicken-interleukin-12 protein 40 (ch-IL-12p40). When administered as adjuvant of the H9N2 IWV vaccine, the minimal dose of T-CpG-AB plasmid was 30 µg per one-day-old chicken, which could induce strong humoral immune responses in the presence of PTAs. Furthermore, T-CpG-AB plasmid-based vaccine triggered both strong humoral immune responses and cytokines expression in the presence of PTAs in chickens. Overall, our findings suggest that T-CpG-AB plasmid can be an excellent adjuvant candidate for the H9N2 IWV vaccine to overcome MDAs interference in chickens.
母源抗体（MDAs）是导致 H9N2 灭活全病毒（IWV）疫苗在禽类中免疫失败的原因之一。未甲基化的 CpG 基序含有寡脱氧核苷酸（CpG ODN）在哺乳动物中显示出克服 MDA 干扰的巨大潜力，但它在禽类中是否具有类似的特性尚不清楚。在本研究中，不同类别的 CpG ODN 基序被克隆到两种不同的质粒（pCDNA3.1 或 T 载体）中。在存在被动转移抗体（PTAs）模拟 MDA 的情况下，在体外和体内测试了这些 CpG ODN 质粒的免疫调节活性和免疫佐剂功效。结果表明，富含 30 个拷贝 CpG-A ODN 和 20 个拷贝 CpG-B ODN 的 T 载体（T-CpG-AB）显著上调了鸡干扰素-α（ch-IFN-α）、鸡干扰素-β（ch-IFN-β）和鸡白细胞介素-12 蛋白 40（ch-IL-12p40）的 mRNA 表达。当作为 H9N2 IWV 疫苗的佐剂使用时，T-CpG-AB 质粒的最小剂量为每只 1 日龄鸡 30µg，在存在 PTAs 的情况下可以诱导强烈的体液免疫反应。此外，在存在 PTAs 的情况下，T-CpG-AB 质粒疫苗可在鸡中引发强烈的体液免疫反应和细胞因子表达。总的来说，我们的研究结果表明，T-CpG-AB 质粒可以成为 H9N2 IWV 疫苗的优秀佐剂候选物，以克服 MDA 对鸡的干扰。
