甲型肝炎病毒吕8株的快速适应性培养

用12天35℃初步适应培育出一株在KMB17细胞稳定传代、感染性滴度高、增殖周期短的HAV适应株LU8株，其感染性滴度为108．33TCID50／ml，抗原滴度为1：1024，一步生长曲线试验和免疫电镜观察结果表明12天为该株病毒增殖高峰。LUB株和H2减毒株HAV经纯化和灭活后接种豚鼠，第一次接种后4周血清HAV抗体均阳转，第二次接种后滴度为1：13．5和1：4．8（GMT），第三次接种后滴度增至1：16和1：8。提示LUB株抗原性较H2株强。

Culture of Rapid Growth-adapted Hepatitis A Virus LU8 Strain

In order to obtain a rapid growth-adapted HAV strain, LU8 strain was cultured in KMB17 cells at 35C for 12 days. The adapted LU8 strain could be stably passaged in KMB17 cells, and the virulence and antigen titers of it were 108.33 TCID50/ml and 1: 1024respectively. One-step growth curve and immunoelectron microscope observation showed that the virus probagation of the adapted LU8 strain reached peak value at the 12th day. Guinea pigs were immunized with the adapted LU8 strain after being purified and inactivated, using attenuated H2 strain as control. Two groups of guinea pigs were separately immunized with the 2 strains (LU6 and H2): both groups were HAV antibody positive at 4 weeks after the 1st dose, and the antibody titers of them were 1: 13. 5 and 1: 4. 8 respectively after the 2nd dose. However, after the 3rd dose, the titers reached 1: 16 and 1: 8 respectively. It indicated that the antigenicity of LU8 strain was stronger than that of H2 strain.