Porcine epidemic diarrhea virus (PEDV) has been prevalent for many years. The viral spike (S) protein is the major target of neutralizing antibodies. However, there is little understanding of the locations of the neutralizing antibody epitopes in the spike structure. Here, we used a polyclonal antibody (pAb) against PEDV and a neutralizing monoclonal antibody (mAb) to isolate escape mutants of PEDV strain LNCT2. Finally, we isolated an escape mutant strain of PEDV, mutant-1B9, but still neutralized by the pAb. Analysis showed two regions deleted in the S protein which allowed mutant-1B9 to escape neutralization by mAb 1B9. These results suggest the deleted amino acids participate in the formation of conformational epitope and provides valuable information for mapping conformational epitopes. Importantly, no PEDV escape mutants were generated by treatment with pAbs, which suggests the potential utility of pAbs or combination therapies based on several mAbs in controlling PEDV infections.

猪流行性腹泻病毒（PEDV）已经流行了很多年。病毒刺突（S）蛋白是中和抗体的主要目标。但是，对中和抗体表位在刺突结构中的位置了解很少。在这里，我们使用了针对PEDV的多克隆抗体（pAb）和中和性单克隆抗体（mAb）来分离PEDV菌株LNCT2的逃避突变体。最后，我们分离了PEDV的逃生突变株，突变株1B9，但仍被pAb中和。分析显示，S蛋白中缺失了两个区域，这使突变体1B9能够被mAb 1B9中和。这些结果表明，缺失的氨基酸参与构象表位的形成，并提供了用于构象表位的有价值的信息。重要的，