Strang B L, Ikeda Y, Cosset F-L, Collins M K L, Takeuchi Y
Department of Immunology and Molecular Pathology, Windeyer Institute of Medical Sciences, University College London, London, UK.
Gene Ther. 2004 Apr;11(7):591-8. doi: 10.1038/sj.gt.3302189.
We have recently described a novel, stable human immunodeficiency virus type 1 (HIV-1) vector packaging system, STAR. High-titre HIV-1 vectors bearing gammaretrovirus envelopes (Env) are continuously produced from STAR cells. Here we compare the properties of such vectors, with the amphotropic murine leukaemia virus (MLV-A) Env, a modified gibbon ape leukaemia virus (GALV) Env and two modified versions of the cat endogenous retrovirus RD114 Env, produced from STAR cells, to transiently produced HIV-1 vectors with vesicular stomatitis virus G protein (VSV-G). Our results indicate that gammaretrovirus pseudotypes from STAR cells are relatively stable at 37 degrees C and are resistant to inactivation by freeze/thaw cycling or incubation with human sera. HIV-1(VSV-G) was, however, sensitive to freeze/thaw when harvested in serum-free media and was readily inactivated in human sera. Furthermore, the titre of 'gamma-retrovirus' pseudotypes, but not HIV-1(VSV-G), could be increased by the use of a combination of polybrene and spinoculation. All pseudotypes could be efficiently concentrated, but soluble gammaretrovirus Env could act as an inhibitor of infection.
我们最近描述了一种新型的、稳定的1型人类免疫缺陷病毒（HIV-1）载体包装系统，即STAR。携带γ逆转录病毒包膜（Env）的高滴度HIV-1载体可从STAR细胞中持续产生。在此，我们将STAR细胞产生的此类载体与嗜异性小鼠白血病病毒（MLV-A）Env、一种修饰的长臂猿白血病病毒（GALV）Env以及猫内源性逆转录病毒RD114 Env的两个修饰版本的特性，与瞬时产生的带有水疱性口炎病毒G蛋白（VSV-G）的HIV-1载体进行比较。我们的结果表明，STAR细胞产生的γ逆转录病毒假型在37℃时相对稳定，并且对冻融循环或与人血清孵育导致的失活具有抗性。然而，HIV-1（VSV-G）在无血清培养基中收获时对冻融敏感，并且在人血清中容易失活。此外，使用聚凝胺和离心接种相结合的方法可提高“γ逆转录病毒”假型的滴度，但对HIV-1（VSV-G）无效。所有假型均可有效浓缩，但可溶性γ逆转录病毒Env可作为感染抑制剂。
