Plum Island Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Orient, NY 11957, USA.
National Bio and Agro-Defense Facility, Agricultural Research Service, U.S. Department of Agriculture, Manhattan, KS 66502, USA.
Viruses. 2023 Oct 8;15(10):2064. doi: 10.3390/v15102064.
ASFV vaccine candidate ASFV-G-ΔI177L has been shown to be highly efficacious in inducing protection against challenges with the parental virus, the Georgia 2010 isolate, as well as against field strains isolated from Vietnam. ASFV-G-ΔI177L has been shown to produce protection even when used at low doses (10 HAD) and shows no residual virulence even when administered at high doses (10 HAD) or evaluated for a relatively long period of time (6 months). ASFV-G-ΔI177L stocks can only be massively produced in primary cell macrophages. Alternatively, its modified version (ASFV-G-ΔI177L/ΔLVR) grows in a swine-derived cell line (PIPEC), acquiring significant genomic modifications. We present here the development of ASFV-G-ΔI177L stocks in a swine macrophage cell line, IPKM, and its protective efficacy when evaluated in domestic pigs. Successive passing of ASFV-G-ΔI177L in IPKM cells produces minimal genomic changes. Interestingly, a stock of ASFV-G-ΔI177L obtained after 10 passages (ASFV-G-ΔI177Lp10) in IPKM cells showed very small genomic changes when compared with the original virus stock. ASFV-G-ΔI177Lp10 conserves similar growth kinetics in primary swine macrophage cultures than the original parental virus ASFV-G-ΔI177L. Pigs infected with 10 HAD of ASFV-G-ΔI177Lp10 developed a strong virus-specific antibody response and were completely protected against the challenge with the parental virulent field isolate Georgia 2010. Therefore, IPKM cells could be an effective alternative for the production of ASFV vaccine stocks for those vaccine candidates exclusively growing in swine macrophages.
ASFV 疫苗候选株 ASFV-G-ΔI177L 已被证明在诱导针对亲本病毒（格鲁吉亚 2010 分离株）以及来自越南的田间分离株的保护方面非常有效。即使使用低剂量（10 HAD），ASFV-G-ΔI177L 也能产生保护作用，即使在高剂量（10 HAD）下使用或在较长时间内（6 个月）进行评估，也没有残留毒力。ASFV-G-ΔI177L 株只能在原代细胞巨噬细胞中大量生产。或者，其改良版本（ASFV-G-ΔI177L/ΔLVR）在猪源性细胞系（PIPEC）中生长，获得显著的基因组修饰。我们在此介绍 ASFV-G-ΔI177L 株在猪源巨噬细胞系 IPKM 中的开发及其在国内猪中的保护效力。ASFV-G-ΔI177L 在 IPKM 细胞中的连续传代产生最小的基因组变化。有趣的是，在 IPKM 细胞中传代 10 次（ASFV-G-ΔI177Lp10）获得的 ASFV-G-ΔI177L 株与原始病毒株相比，基因组变化非常小。ASFV-G-ΔI177Lp10 在原代猪巨噬细胞培养物中保持与原始亲本病毒 ASFV-G-ΔI177L 相似的生长动力学。感染 10 HAD 的 ASFV-G-ΔI177Lp10 的猪产生强烈的病毒特异性抗体反应，并完全免受亲本强毒力田间分离株格鲁吉亚 2010 的挑战。因此，IPKM 细胞可能是那些专门在猪巨噬细胞中生长的 ASFV 疫苗候选株生产疫苗的有效替代方法。
