Stim T B
Appl Microbiol. 1970 May;19(5):757. doi: 10.1128/am.19.5.757-762.1970.
Dengue type 2 virus, strain New Guinea B, plaqued with equal facility and titer under overlays containing six different grades of commercial agar in the LLC-MK(2) cell system. Doubling the agar volume on LLC-MK(2) cell monolayers increased the plaque development time of dengue type 1, strain Hawaii. Storage of agar at 56 C reduced or totally abolished dengue type 4, strain H-241, plaque titer in LLC-MK(2) cells. The influence of six known virus plaque-enhancing compounds on plaque development of all dengue virus serotypes was studied in two continuous simian kidney cell lines, LLC-MK(2) and Vero. In the absence of any chemical additive, plaque development of all dengue serotypes was more rapid (4 to 10 days) in the LLC-MK(2) line than in the Vero line (6 to 13 days). Increased plaque development time of type 1, strain Hawaii, by pancreatin and plaque-size doubling of dengue types 1 and 4 was the only advantage conferred by the addition of six chemical additives in the LLC-MK(2) cell system. Dengue types 1 and 6 failed to plaque in the Vero cell system unless aided by a plaque-enhancing compound; plaques of dengue types 2, 3, 4, and 5 appeared sooner (2 days) and were increased in plaque diameter. The optimal DEAE concentration for plaquing dengue type 1, strain Hawaii, was 100 mug/ml; plaque development either failed at lower concentrations or was inhibited at higher (200 mug/ml) concentrations.
在LLC-MK(2)细胞系统中，2型登革病毒新几内亚B株在含有六种不同等级商业琼脂的覆盖物下，能以相同的难易程度和滴度形成蚀斑。在LLC-MK(2)细胞单层上使琼脂体积加倍，可延长1型夏威夷株登革病毒的蚀斑形成时间。将琼脂储存在56℃会降低或完全消除4型H-241株登革病毒在LLC-MK(2)细胞中的蚀斑滴度。在两种连续的猴肾细胞系LLC-MK(2)和Vero中，研究了六种已知的病毒蚀斑增强化合物对所有登革病毒血清型蚀斑形成的影响。在没有任何化学添加剂的情况下，所有登革病毒血清型在LLC-MK(2)细胞系中的蚀斑形成速度更快（4至10天），而在Vero细胞系中则较慢（6至13天）。在LLC-MK(2)细胞系统中添加六种化学添加剂，唯一的优势是胰蛋白酶可延长1型夏威夷株的蚀斑形成时间，以及1型和4型登革病毒的蚀斑大小加倍。1型和6型登革病毒在Vero细胞系统中无法形成蚀斑，除非有蚀斑增强化合物的辅助；2型、3型、4型和5型登革病毒的蚀斑出现得更早（2天），且蚀斑直径增大。用于1型夏威夷株登革病毒蚀斑形成的最佳二乙氨基乙基（DEAE）浓度为100微克/毫升；浓度较低时蚀斑形成失败，浓度较高（200微克/毫升）时蚀斑形成受到抑制。
