Lee Young-Hyeon, Jung Bo-Kyoung, Kim Song-Yi, Kim Dohyun, Jang Min-Kyung, Choe SeEun, An Byung-Hyun, Kim Jae-Jo, Cho Yun Sang, An Dong-Jun
Virus Disease Division, Animal and Plant Quarantine Agency, Gimcheon 39660, Gyeongbuk-do, Republic of Korea.
Department of Virology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea.
Viruses. 2025 Apr 5;17(4):529. doi: 10.3390/v17040529.
A chimeric KD26_E2LOM strain can induce antibodies that can be partially distinguished from antibodies from classical swine fever virus (CSFV) infection. The chimeric vaccine strain was created using bovine viral diarrhea virus as the backbone; however, the entire BVDV E2 gene region was replaced with the E2 gene, which encodes the major target for neutralizing antibodies against CSFV. Pigs were vaccinated once or twice with the chimeric KD26_E2LOM strain, and protective efficacy was evaluated after subsequent challenge with virulent CSFV. Pigs inoculated with the chimeric KD26_E2LOM strain did not have a high temperature or leukopenia, and CSFV neutralizing antibodies (>64-fold) were observed from 28 days postvaccination (dpv). In addition, the level of anti-CSFV E2 antibody positivity was >0.8 (s/ value) from 30 dpv, and there were no antibody-positive individuals among the sentinel pigs. In control pigs, CSF antigen was detected in blood, nasal, and fecal samples at 5, 7, 10, 14, and 21 days postchallenge (dpc) and in several organs; however, no CSFV was detected in the organs of pigs vaccinated with the chimeric KD26_E2LOM strain, and no virus shedding or CSF antigen was detected on any dpc. Thus, the chimeric KD26_E2LOM strain protects pigs against horizontal transmission of virulent CSFV; however, this strain may have only partial potential for the differential detection of CSFV E antibodies.
嵌合KD26_E2LOM毒株可诱导产生能与经典猪瘟病毒（CSFV）感染所产生抗体部分区分开来的抗体。该嵌合疫苗毒株是以牛病毒性腹泻病毒为骨架构建的；然而，整个牛病毒性腹泻病毒E2基因区域被编码针对CSFV中和抗体主要靶点的E2基因所取代。用嵌合KD26_E2LOM毒株对猪进行一次或两次免疫接种，随后用强毒CSFV攻击后评估其保护效力。接种嵌合KD26_E2LOM毒株的猪未出现高温或白细胞减少情况，且在接种后28天（dpv）观察到CSFV中和抗体（>64倍）。此外，从30 dpv起，抗CSFV E2抗体阳性水平>0.8（s/值），且哨兵猪中无抗体阳性个体。在对照猪中，攻毒后5、7、10、14和21天（dpc）在血液、鼻腔和粪便样本以及多个器官中检测到CSF抗原；然而，在接种嵌合KD26_E2LOM毒株的猪的器官中未检测到CSFV，且在任何dpc均未检测到病毒 shedding或CSF抗原。因此，嵌合KD26_E2LOM毒株可保护猪免受强毒CSFV的水平传播；然而，该毒株在CSFV E抗体的鉴别检测方面可能仅具有部分潜力。
