Luo Y, Chen X, Han R, O'Donnell M A
Division of Urology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Clin Exp Immunol. 2001 Feb;123(2):264-70. doi: 10.1046/j.1365-2249.2001.01428.x.
To increase its immunostimulatory properties, BCG was genetically engineered to secrete recombinant human interferon-alpha 2B (rhIFN-alpha) under control of the mycobacterial heat shock protein (hsp)60 promoter and the alpha antigen signal sequence. Expression of rhIFN-alpha was readily detectable by ELISA and on Western blotting. When compared with control BCG, rhIFN-alpha BCG was substantially more active in inducing the production of IFN-gamma and IFN-inducible protein 10 (IP-10) from human peripheral blood mononuclear cells, while IL-10 production was correspondingly decreased. These effects were reversible upon antibody neutralization of rhIFN-alpha. Among 10 patients tested, rhIFN-alpha BCG enhanced IFN-gamma production in all patients ranging from 1.4- to 23.7-fold with a general trend toward greatest enhancement among those with weakest baseline responses to control BCG. Correspondingly, rhIFN-alpha BCG decreased IL-10 production in all patients by 1.2-4.8-fold. The onset of IFN-gamma production induced by rhIFN-alpha BCG was also more rapid, occurring within 4 h after stimulation versus > 24 h with wild-type BCG. The observation that the maximum IFN-gamma induction depends on the simultaneous presence of both IFN-alpha and BCG highlights the advantages of rhIFN-alpha BCG. Taken together, these immunostimulatory properties of rhIFN-alpha BCG suggest that it may be a superior agent for immunotherapeutic protocols involving live BCG in humans.
为增强其免疫刺激特性，卡介苗经基因工程改造，使其在分枝杆菌热休克蛋白（hsp）60启动子和α抗原信号序列的控制下分泌重组人干扰素-α 2B（rhIFN-α）。通过酶联免疫吸附测定（ELISA）和蛋白质印迹法可轻易检测到rhIFN-α的表达。与对照卡介苗相比，rhIFN-α卡介苗在诱导人外周血单个核细胞产生γ干扰素（IFN-γ）和干扰素诱导蛋白10（IP-10）方面活性显著更高，而白细胞介素10（IL-10）的产生相应减少。这些效应在rhIFN-α抗体中和后是可逆的。在接受测试的10名患者中，rhIFN-α卡介苗使所有患者的IFN-γ产生增强了1.4至23.7倍，总体趋势是在对对照卡介苗基线反应最弱的患者中增强最为显著。相应地，rhIFN-α卡介苗使所有患者的IL-10产生减少了1.2至4.8倍。rhIFN-α卡介苗诱导的IFN-γ产生的起始也更快，在刺激后4小时内出现，而野生型卡介苗则超过24小时。最大IFN-γ诱导依赖于IFN-α和卡介苗同时存在这一观察结果突出了rhIFN-α卡介苗的优势。综上所述，rhIFN-α卡介苗的这些免疫刺激特性表明，它可能是人类中涉及活卡介苗的免疫治疗方案的一种更优药物。
