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EB病毒溶裂循環及溶裂基因表現的相關研究，均因缺乏適當的分析系統而
使得工作顯得複雜而且困難。B95-8 細胞株是 EB 病毒的原生型病毒株，
經常被拿來與其它病毒株的溶裂基因表現互相比較。根據前人研究發現，
B95-8 細胞株會受到TPA 誘導，而活化病毒的溶裂循環，其溶裂時期表現
的基因估計在80種以上。然而已知的溶裂基因仍侷現在所知的幾個基因表
現而已。本論文之目的是利用高敏感度的螢光酵素基因做為報導系統，構
築由病毒溶裂基因所驅動的報導基因質體，並且觀察受到TPA 誘導下，病
毒基因表現的時間性及順序性。由病毒極早期基因BZLF1 及晚期基因
VCA 所驅動的報導基因質體表現，均證明受到TPA 的誘導而活化起動子的
表現。並就蛋白的表現層次，分別以免疫染色法及西方墨點法證實病毒溶
裂基因BZLF1 蛋白，EA，VCA 經過誘導表現後，表現量上升的情形與報導
基因所偵測之結果一致。藉著報導基因在不同細胞株中的表現結果，發現
病毒溶裂基因的活化可能與細胞蛋白有密切的關係。綜合報導基因質體
在 EBV﹣ 及 EBV﹢B 淋巴球細胞株，及經過 B95-8 病毒株感染後的細
胞株其螢光觀測值上的差異，發現除了不同細胞蛋白可能對病毒溶裂基因
產生影響外，病毒本身所主導的蛋白也有不容忽視的重要性，並利用抗藥
基因的共同篩選得到可穩定表現螢光酵素的細胞株，提供便利於研究病毒
溶裂基因表現的材料。
Epstein-Barr Virus (EBV) is a human herpesvirus which can enter
a latent or a lytic cycle in B lymphocytes.This virus has a
restricted host range and persists in the B cell in a
nonproductive latent phase. So far, a permissive cell system
for the replication of EBV has not been established and the
mechanism triggering productive cycle from the latent state is
complex. In this thesis, a firefly luciferase luc reporter
system was used for the study of the expression of lytic genes
in B lymphocytes. Studies revealed that transfection with 10 ug
of plasmid DNA into 5*10 cells gave an optimal expression of
luc in the cells. Results also showed that BZLF1 promoter
expression was detectable 24 hours after TPA induction. The
expression reached to the highest level between 36-48 hours.
This result was also confirmed by Western analysis. Contrary to
general belief that VCA gene was a late gene, the VCA promoter
was expressed early and was co-expressed with BZLF1 promoter.
This reporter system was also used to study the lytic
replication of a non-productive EBV-containing B-lymphocyte
cell line, CG3. Results suggested that low-level expression of
the BZLF1 promoter expression may contribute to the low-level
synthesis of viral particles in the cells. The results also
showed that BZLF1 promoter was not expressed in EBV- B
lymphocytes. On the other hand, the activity of the promoter
increased when the BZLF1 promoter was transfected into the
cells immediately after EBV infection, suggesting that unknown
factors encoded by EBV may be required for the expression of
BZLF1. Cell lines with BZLF1-luc, Dp-luc, VCA-luc stably
integrted in the chromosomes of B95-8 cells were also
established. These cells will be useful for the studey of
external factors that may affect the expression of these genes.
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