http://www.100md.com 2007年10月18日 潘孝本, 韩进超, 魏 来, 高 燕, 丛 旭
潘孝本, 韩进超, 魏来, 高燕, 丛旭, 北京大学肝病研究所 北京大学人民医院 北京市100044
国家自然科学基金资助项目, No. 30700697
国家“973”计划资助项目, No. 2005CB522902
通讯作者: 魏来, 100044, 北京市西城区西直门南大街11号, 北京大学人民医院, 北京大学肝病研究所. firstname.lastname@example.org
电话: 010-88325566 传真: 010-68318386
收稿日期: 2007-08-06 修回日期: 2007-09-25
Dimethyl sulphoxide facilitates the nuclear entry of hepatitis B virus core protein in infected HepG2 cells
Xiao-Ben Pan, Jin-Chao Han, Lai Wei, Yan Gao, Xu Cong
Xiao-Ben Pan, Jin-Chao Han, Lai Wei, Yan Gao, Xu Cong, People’s Hospital of Peking University, Hepatology Institute of Peking University, Beijing 100044, China
Supported by: National Natural Science Foundation of China, No. 30700697 and National Basic Research Program of China, No. 2005CB522902
Correspondence to: Lai Wei, People’s Hospital of Peking University, Hepatology Institute of Peking University, 11 Xizhimen South Street, Beijing 100044, China. email@example.com
Received: 2007-08-06 Revised: 2007-09-25
AIM: To study the effect of dimethyl sulphoxide on the nuclear entry of hepatitis B virus core protein in infected HepG2 cells.
METHODS: In the DMSO and control groups, HepG2 cells were cultured in DMEM with or without 2% DMSO for 4 d. Then the cells were incubated with HBV (1000 copies per cells) for 12 hours at 37℃. Hepatitis B core antigen (HBcAg) in the infected HepG2 cells was stained by fluorescent immunocytochemistry and observed by confocal microscopy. HBcAg in the cytoplasm and nucleus was respectively extracted and analyzed by Western blotting. HBV covalently closed circular DNA (cccDNA) was detected by ploymerase chain reaction, and cell cycle was analyzed by flow cytometry.
RESULTS: In control HepG2 cells, HBcAg was mostly expressed in cytoplasm and almost absent from the nucleus, and it disappeared from the cells at 2 days post infection (PI). No obvious sign of cccDNA was detected in the control group at 2 days. After DMSO administration, compared with that of control group, a higher level of HBcAg was detected in the cytoplasm at 12 hours PI. HBcAg was accumulated around the nucleus at 24 hours PI. The level of HBcAg in the nucleus obviously increased and cccDNA was present at 24 and 48 hours PI. Flow cytometry showed that DMSO increased the ratio of G1/G0 and G2/M phases of HepG2 cells. HBcAg was distributed throughout the cells in mitosis phase HepG2 cells.
CONCLUSION: In HepG2 cells, blocking the entry of core particles to the nucleus might be an important reason for the cells being refractory to HBV infection. DMSO promotes nuclear entry of core protein/core particles and then facilitates HBV infection.
Key Words: HepG2; Hepatitis B virus; Infection; Dimethyl sulphoxide; Western bloting; Flow cytometry
Pan XB, Han JC, Wei L, Gao Y, Cong X. Dimethyl sulphoxide facilitates the nuclear entry of hepatitis B virus core protein in infected HepG2 cells ......