PDF(Pubmed)
Abstract：
The emergence of SARS-CoV-2 in late 2019 initiated a global pandemic, which led to a need for effective therapeutics and diagnostic tools, including virus-specific antibodies. Here, we investigate different antigen preparations to produce SARS-CoV-2-specific and virus-neutralizing antibodies in chickens (n = 3/antigen) and rabbits (n = 2/antigen), exploring, in particular, egg yolk for large-scale production of immunoglobulin Y (IgY). Reactivity profiles of IgY preparations from chicken sera and yolk and rabbit sera were tested in parallel. We compared three types of antigens based on ancestral SARS-CoV-2: an inactivated whole-virus preparation, an S1 spike-protein subunit (S1 antigen) and a receptor-binding domain (RBD antigen, amino acids 319-519) coated on lumazine synthase (LS) particles using SpyCather/SpyTag technology. The RBD antigen proved to be the most efficient immunogen, and the resulting chicken IgY antibodies derived from serum or yolk, displayed strong reactivity with ELISA and indirect immunofluorescence and broad neutralizing activity against SARS-CoV-2 variants, including Omicron BA.1 and BA.5. Preliminary in vivo studies using RBD-lumazine synthase yolk preparations in a hamster model showed that local application was well tolerated and not harmful. However, despite the in vitro neutralizing capacity, this antibody preparation did not show protective effect. Further studies on galenic properties seem to be necessary. The RBD-lumazine antigen proved to be suitable for producing SARS-CoV-2 specific antibodies that can be applied to such therapeutic approaches and as reference reagents for SARS-CoV-2 diagnostics, including virus neutralization assays.
摘要：
2019年底SARS-CoV-2的出现引发了全球大流行，这导致了对有效治疗和诊断工具的需求，包括病毒特异性抗体.这里,我们研究了在鸡（n=3/抗原）和兔（n=2/抗原）中产生SARS-CoV-2特异性和病毒中和抗体的不同抗原制剂，探索,特别是,用于大规模生产免疫球蛋白Y（IgY）的蛋黄。平行测试来自鸡血清和蛋黄和兔血清的IgY制剂的反应性特征。我们比较了基于祖先SARS-CoV-2的三种类型的抗原：一种灭活的全病毒制剂，S1刺突蛋白亚基(S1抗原)和受体结合域(RBD抗原，氨基酸319-519）使用SpyCather/SpyTag技术涂覆在lumazine合酶（LS）颗粒上。RBD抗原被证明是最有效的免疫原，以及来自血清或蛋黄的鸡IgY抗体，与ELISA和间接免疫荧光以及对SARS-CoV-2变体的广泛中和活性表现出强反应性，包括OmicronBA.1和BA.5。在仓鼠模型中使用RBD-lumazine合酶卵黄制剂的初步体内研究表明，局部应用耐受性良好，无害。然而,尽管有体外中和能力，这种抗体制剂没有显示出保护作用。对盖伦特性的进一步研究似乎是必要的。RBD-lumazine抗原被证明适用于产生SARS-CoV-2特异性抗体，可用于此类治疗方法并作为SARS-CoV-2诊断的参考试剂，包括病毒中和试验。
