Zhou C F, Abe K, Wang P, Ojima T, Yamamoto K
Department of Virology, Medical Research Institute, Tokyo Medical and Dental University, Japan.
Microbiol Immunol. 1999;43(5):425-36. doi: 10.1111/j.1348-0421.1999.tb02426.x.
The efficient propagation of the OK strain of the B variant of human herpesvirus 6 (HHV-6B) was demonstrated in a line of T cells, TaY, established from the peripheral blood lymphocytes of a patient with adult T-cell leukemia/lymphoma (ATL). Growth of TaY cells depends on the presence of IL-2 and the cells harbor HTLV-I genomes. A severe cytopathic effect (CPE) was observed in many HHV-6B(OK)-infected TaY cells one week after infection. The release of virus from HHV-6B(OK)-infected TaY cells [TaY(OK)] was first detected after three days and increased rapidly for up to seven days after infection, as demonstrated by PCR. The titer of HHV-6B(OK) in the supernatant was comparable to the value of 10(3.5) TCID50/ml obtained with PHA-activated cord blood lymphocytes (CBL) that had been infected with HHV-6B(OK). The replication of the virus was shown to depend to a considerable extent on cell viability. Electron microscopy revealed many herpesvirus-type capsid- and enveloped-viruses in the nuclei and cytoplasm of degenerated cells in TaY(OK) cultures. The U1102 strain of HHV-6A and the Z29 strain of HHV-6B also infected TaY cells productively, as detected by PCR and an immunofluorescence test. These results suggest that the activation of CD4+ T lymphocytes with mitogens such as PHA or IL-2 and the expression of some cellular gene or the HTLV-I gene might be essential for efficient propagation of HHV-6B. TaY cells should play an important role in future investigations of cell-virus interactions and genetic variations or cell tropism of HHV-6 isolates since no cell line that shows propagation of both HHV-6A and HHV-6B has been reported to date.
在从一名成人T细胞白血病/淋巴瘤（ATL）患者外周血淋巴细胞建立的T细胞系TaY中，证实了人类疱疹病毒6型B变体（HHV - 6B）OK株的有效增殖。TaY细胞的生长依赖于IL - 2的存在，且这些细胞含有HTLV - I基因组。感染HHV - 6B(OK)一周后，在许多感染的TaY细胞中观察到严重的细胞病变效应（CPE）。PCR结果显示，感染HHV - 6B(OK)的TaY细胞[TaY(OK)]在感染三天后首次检测到病毒释放，且在感染后长达七天内迅速增加。上清液中HHV - 6B(OK)的滴度与用PHA激活的、感染了HHV - 6B(OK)的脐血淋巴细胞（CBL）获得的10(3.5) TCID50/ml的值相当。结果表明，病毒的复制在很大程度上依赖于细胞活力。电子显微镜显示，在TaY(OK)培养物中退化细胞的细胞核和细胞质中有许多疱疹病毒型衣壳病毒和包膜病毒。通过PCR和免疫荧光试验检测发现，HHV - 6A的U1102株和HHV - 6B的Z29株也能有效感染TaY细胞。这些结果表明，用PHA或IL - 2等丝裂原激活CD4 + T淋巴细胞以及某些细胞基因或HTLV - I基因的表达可能是HHV - 6B有效增殖所必需的。由于迄今为止尚未报道有细胞系能同时支持HHV - 6A和HHV - 6B的增殖，TaY细胞在未来HHV - 6分离株的细胞 - 病毒相互作用、基因变异或细胞嗜性研究中应发挥重要作用。
