Maas Riks, van Zoelen Diana, Oei Hok, Claassen Ivo
Central Institute of Animal Disease Control (CIDC) Lelystad, P.O. Box 2004, 8203 AA Lelystad, The Netherlands.
Biologicals. 2006 Sep;34(3):177-81. doi: 10.1016/j.biologicals.2005.09.002. Epub 2005 Oct 28.
International regulations prescribe that the absence of avian leucosis viruses (ALV) in avian live virus vaccines has to be demonstrated. Primary chicken embryo fibroblasts (CEF) from special SPF chicken lines are normally used for detection of ALV. The suitability of the DF-1 cell line for ALV-detection, as alternative for primary CEF, was studied in three types of experiments: (1) in titration experiments without cell passage, (2) in experiments with passages in cell cultures according to European Pharmacopoeia requirements, and (3) in experiments with commercial live avian vaccines that had been spiked with known amounts of ALV. In all tests the sensitivity of ALV-A and ALV-J detections on DF-1 cells was at least as high as on primary CEF. The sensitivity of ALV-B detection was always superior when DF-1 cells were used. ALV were detected earlier in all comparative tests when DF-1 cells were used. ALV-A, ALV-B and ALV-J all induced CPE on DF-1 cells, whereas no clear CPE was seen on CEF-cells. For reasons of sensitivity, standardisation as well as reduction of animal use, the data support the use of DF-1 cells to monitor absence of ALV in vaccine virus seed lots or finished products.
国际法规规定，必须证明禽活病毒疫苗中不存在禽白血病病毒（ALV）。通常使用来自特殊无特定病原体（SPF）鸡系的原代鸡胚成纤维细胞（CEF）来检测ALV。在三类实验中研究了DF-1细胞系作为原代CEF的替代物用于检测ALV的适用性：（1）在无细胞传代的滴定实验中；（2）在根据欧洲药典要求在细胞培养中传代的实验中；（3）在添加了已知量ALV的商业禽活疫苗实验中。在所有测试中，DF-1细胞上检测ALV-A和ALV-J的灵敏度至少与原代CEF上的一样高。使用DF-1细胞时，ALV-B检测的灵敏度始终更高。在所有比较测试中，使用DF-1细胞时能更早地检测到ALV。ALV-A、ALV-B和ALV-J均可在DF-1细胞上诱导细胞病变效应（CPE），而在CEF细胞上未见明显的CPE。出于灵敏度、标准化以及减少动物使用的原因，这些数据支持使用DF-1细胞来监测疫苗病毒种子批或成品中是否存在ALV。
