Valero Yulema, López-Vázquez Carmen, Souto Sandra, Olveira José G, Cuesta Alberto, Bandín Isabel
Instituto de Acuicultura, Departament of Microbiology and Parasitology, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Immunobiology for Aquaculture Group, Department of Cell Biology and Histology, Facultad de Biología, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", Universidad de Murcia, 30100 Murcia, Spain.
Pathogens. 2021 Nov 30;10(12):1565. doi: 10.3390/pathogens10121565.
Viral encephalopathy and retinopathy caused by nervous necrosis virus (NNV), is one of the most threatening viral diseases affecting marine fish worldwide. In vitro propagation of NNV strains is essential for the design of effective control measures. In the present study we analysed both the susceptibility and the permissiveness of five fish cell lines (E-11, GF-1, SAF-1, DLB-1, and SaB-1) to three NNV strains (one RGNNV, one SJNNV, and one reassortant RGNNV/SJNNV). E-11 and DLB-1 were demonstrated to be highly susceptible to NNV strains, with average adsorption efficiency (AE) values higher than 90%. SAF-1 also showed high susceptibility (AE 88%), whereas GF-1 can be regarded as moderately susceptible (AE around 50%). On the contrary, SaB-1 can be considered a poorly susceptible cell line (AE values below 20%). E-11 and GF-1 cell lines provided the highest production rates for RGNNV and RG/SJ (around 10) and both cell lines can be regarded as fully permissive for these viral types. However, the SJNNV production rate in GF-1 was only 17.8 and therefore this cell line should be considered semi-permissive for this genotype. In SAF-1 cells, moderate viral replication was recorded but differences in intracellular and extracellular production suggest that viral progeny was not efficiently released. In DLB-1 and SaB-1 the final viral titres obtained in E-11 were lower than those of the inoculum. However, RNA1 synthesis values seem to indicate that RGNNV replication in DLB-1 and SAF-1 could have been underestimated, probably due to a poor adaptation of the virus grown in these cell lines to E-11. Based on all these results, E-11 seems to be the most appropriate cell for in vitro culture of RGNNV, SJNNV, and reassortant strains.
由神经坏死病毒（NNV）引起的病毒性脑病和视网膜病是影响全球海洋鱼类的最具威胁性的病毒性疾病之一。NNV毒株的体外增殖对于设计有效的控制措施至关重要。在本研究中，我们分析了五种鱼类细胞系（E-11、GF-1、SAF-1、DLB-1和SaB-1）对三种NNV毒株（一种RGNNV、一种SJNNV和一种重组RGNNV/SJNNV）的敏感性和允许性。结果表明，E-11和DLB-1对NNV毒株高度敏感，平均吸附效率（AE）值高于90%。SAF-1也表现出高敏感性（AE为88%），而GF-1可被视为中度敏感（AE约为50%）。相反，SaB-1可被认为是敏感性较差的细胞系（AE值低于20%）。E-11和GF-1细胞系对RGNNV和RG/SJ的生产率最高（约为10），这两种细胞系可被视为对这些病毒类型完全允许。然而，GF-1中SJNNV的生产率仅为17.8，因此该细胞系对该基因型应被视为半允许。在SAF-1细胞中，记录到适度的病毒复制，但细胞内和细胞外产生的差异表明病毒后代没有有效释放。在DLB-1和SaB-1中，在E-11中获得的最终病毒滴度低于接种物。然而，RNA1合成值似乎表明，RGNNV在DLB-1和SAF-1中的复制可能被低估了，这可能是由于在这些细胞系中生长的病毒对E-11的适应性较差。基于所有这些结果，E-11似乎是体外培养RGNNV、SJNNV和重组毒株的最合适细胞。
