Porcine deltacoronavirus (PDCoV) is an emerging coronavirus that causes vomiting, diarrhea, dehydration, and even death of piglets, resulting in significant losses to the pig industry worldwide. However, the epitopes of PDCoV remain largely unknown. In this study, a monoclonal antibody (mAb) against the PDCoV nucleocapsid (N) protein, termed 9G1, was prepared using the lymphocyte hybridoma technique, and was identified as a type IgG1 with a κ light chain and reacted with the native N protein of PDCoV. Furthermore, the epitope recognized by the 9G1 mAb was subjected to western blot and an ELISA using truncated recombinant proteins and synthetic polypeptides of the PDCoV N protein. The results indicate that 9G1 mAb recognized the epitope, G⁵⁹TPIPPSYAFYY⁷⁰ (EP-9G1), a novel linear B cell epitope of the PDCoV N protein. A comparison analysis revealed that the EP-9G1 epitope was highly conserved among PDCoV strains, in which four residues (G⁵⁹—F⁶⁸YY⁷⁰) were observed among different coronavirus genera. These data demonstrate that the EP-9G1 epitope identified in this study provides some basic information for further characterization of the antigenic structure of the PDCoV N protein and has potential use for developing diagnostic reagents for PDCoV.

猪三角型冠状病毒 (PDCoV) 是一种新兴的冠状病毒，可引起仔猪呕吐、腹泻、脱水甚至死亡，给全球养猪业造成重大损失。然而，PDCoV 的表位在很大程度上仍然未知。在这项研究中，使用淋巴细胞杂交瘤技术制备了一种针对 PDCoV 核衣壳 (N) 蛋白的单克隆抗体 (mAb)，称为 9G1，并被鉴定为具有 κ 轻链的 IgG1 型，并与 PDCoV 的天然 N 蛋白发生反应。 PDCoV。此外，使用截短的重组蛋白和 PDCoV N 蛋白的合成多肽，对 9G1 mAb 识别的表位进行了蛋白质印迹和 ELISA。结果表明 9G1 mAb 识别表位，G ⁵⁹ TPIPPSYAFYY ⁷⁰(EP-9G1)，PDCoV N 蛋白的一种新型线性 B 细胞表位。比较分析表明，EP-9G1表位在PDCoV毒株中高度保守，在不同冠状病毒属中观察到4个残基（G ⁵⁹ —F ⁶⁸ YY ^{70 ）。}这些数据表明，本研究中鉴定的 EP-9G1 表位为进一步表征 PDCoV N 蛋白的抗原结构提供了一些基本信息，并具有开发 PDCoV 诊断试剂的潜在用途。