Abstract:
Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) has developed substantial antigenic variability. As the majority of the population now has pre-existing immunity due to infection or vaccination, the use of experimentally generated animal immune sera can be valuable for measuring antigenic differences between virus variants. Here, we immunized Syrian hamsters by two successive infections with one of nine SARS-CoV-2 variants. Their sera were titrated against 16 SARS-CoV-2 variants, and the resulting titers were visualized using antigenic cartography. The antigenic map shows a condensed cluster containing all pre-Omicron variants (D614G, Alpha, Delta, Beta, Mu, and an engineered B.1+E484K variant) and considerably more diversity among a selected panel of Omicron subvariants (BA.1, BA.2, BA.4/BA.5, the BA.5 descendants BF.7 and BQ.1.18, the BA.2.75 descendant BN.1.3.1, the BA.2-derived recombinants XBB.2 and EG.5.1, and the BA.2.86 descendant JN.1). Some Omicron subvariants were as antigenically distinct from each other as the wildtype is from the Omicron BA.1 variant. Compared to titers measured in human sera, titers in hamster sera are of higher magnitude, show less fold change, and result in a more compact antigenic map topology. The results highlight the potential of sera from hamsters for the continued antigenic characterization of SARS-CoV-2.
摘要:
严重急性呼吸道综合征冠状病毒2(SARS-CoV-2)已发展出大量的抗原变异性。由于大多数人现在由于感染或疫苗接种而具有预先存在的免疫力,使用实验产生的动物免疫血清对于测量病毒变体之间的抗原差异可能是有价值的。这里,我们用9种SARS-CoV-2变种中的一种连续两次感染对叙利亚仓鼠进行了免疫接种。他们的血清针对16种SARS-CoV-2变体进行了滴定,并使用抗原制图可视化所得滴度。抗原图谱显示了一个含有所有pre-Omicron变体的凝聚簇(D614G,阿尔法,Delta,Beta,穆,和工程化的B.1E484K变体),并且在选定的一组Omicron亚变体(BA.1,BA.2,BA4/BA.5,BA.5后代BF.7和BQ.1.18,BA.2.75后代BN.1.3.1,BA.2衍生的重组体XBB.2和EG.5.1以及BA.2.86后代JN.1)中具有更大的多样性。一些Omicron亚变体在抗原上彼此不同,因为野生型来自OmicronBA.1变体。与在人血清中测量的滴度相比,仓鼠血清滴度较高,显示较少的折叠变化,并导致更紧凑的抗原图拓扑。结果突出了仓鼠血清对SARS-CoV-2的持续抗原表征的潜力。