Abstract:
We have previously reported that the recombinant African Swine Fever (ASF) vaccine candidate ASFV-G-Δ9GL/ΔUK efficiently induces protection in domestic pigs challenged with the virulent strain Georgia 2010 (ASFV-G). As reported, ASFV-G-Δ9GL/ΔUK induces protection, while intramuscularly (IM), administered at doses of 104 HAD50 or higher, prevents ASF clinical disease in animals infected with the homologous ASFV g strain. Like other recombinant vaccine candidates obtained from ASFV field isolates, ASFV-G-Δ9GL/ΔUK stocks need to be produced in primary cultures of swine macrophages, which constitutes an important limitation in the production of large virus stocks at the industrial level. Here, we describe the development of ASFV-G-Δ9GL/ΔUK stocks using IPKM (Immortalized Porcine Kidney Macrophage) cells, which are derived from swine macrophages. We show that ten successive passages of ASFV-G-Δ9GL/ΔUK in IPKM cells induced small changes in the virus genome. The produced virus, ASFV-G-Δ9GL/ΔUKp10, presented a similar level of replication in swine macrophages cultures to that of the original ASFV-G-Δ9GL/ΔUK (ASFV-G-Δ9GL/ΔUKp0). The protective efficacy of ASFV-G-Δ9GL/ΔUKp10 was evaluated in pigs that were IM-inoculated with either 104 or 106 HAD50 of ASFV-G-Δ9GL/ΔUKp10. While animals inoculated with 104 HAD50 present a partial protection against the experimental infection with the virulent parental virus ASFV-G, those inoculated with 106 HAD50 were completely protected. Therefore, as was just recently reported for another ASF vaccine candidate, ASFV-G-ΔI177L, IPKM cells are an effective alternative to produce stocks for vaccine strains which only grow in swine macrophages.
摘要:
我们以前曾报道过,重组非洲猪瘟(ASF)疫苗候选物ASFV-G-Δ9GL/ΔUK可有效诱导受到力毒株格鲁吉亚2010(ASFV-G)攻击的家猪的保护。据报道,ASFV-G-Δ9GL/ΔUK诱导保护,而肌肉内(IM),以104HAD50或更高的剂量给药,预防感染同源ASFVg菌株的动物的ASF临床疾病。像从ASFV现场分离物中获得的其他重组疫苗候选物一样,ASFV-G-Δ9GL/ΔUK库存需要在猪巨噬细胞的原代培养物中产生,这构成了在工业水平上生产大型病毒库存的重要限制。这里,我们使用IPKM(永生化猪肾巨噬细胞)细胞描述ASFV-G-Δ9GL/ΔUK库存的发展,来源于猪巨噬细胞。我们表明,IPKM细胞中ASFV-G-Δ9GL/ΔUK的十次连续传代诱导了病毒基因组的微小变化。产生的病毒,ASFV-G-Δ9GL/ΔUKp10在猪巨噬细胞培养物中的复制水平与原始ASFV-G-Δ9GL/ΔUK(ASFV-G-Δ9GL/ΔUKp0)相似。在IM接种104或106HAD50的ASFV-G-Δ9GL/ΔUKp10的猪中评估了ASFV-G-Δ9GL/ΔUKp10的保护功效。虽然接种了104HAD50的动物对毒力亲本病毒ASFV-G的实验性感染具有部分保护作用,接种了106HAD50的人得到了完全保护.因此,正如最近报道的另一种ASF候选疫苗,ASFV-G-ΔI177L,IPKM细胞是产生仅在猪巨噬细胞中生长的疫苗株的储备的有效替代方案。