Gaertner Frank H, Babiuk Lorne A, Van Moorlehem Elaine A, Beskorwayne Terry K, Lee Stacey L, Shutter Robert W, Armstrong Janna M, Griebel Philip J
J Control Release. 2005 Oct 3;107(2):189-202. doi: 10.1016/j.jconrel.2005.06.008.
Recombinant Pseudomonas fluorescens cells, expressing over 40% protein as bovine interferon-gamma (IFN-gamma), were chemically fixed to sterilize the culture and amend the bacterial cell wall. When killed and fixed recombinant cells, termed here amended-recombinant-cells (ARCs), were assayed for interferon activity, we obtained the following surprising results: 1) sterilization and fixation did not inactivate ARC-encapsulated IFN-gamma; 2) ARC-encapsulated IFN-gamma and soluble, recombinant IFN-gamma were equally active in vitro but proteolysis was required for release of the ARC cytokine; and 3) ARC-encapsulated IFN-gamma was active in vivo with optimal adjuvant activity at a dose about 1000-fold less than previously reported for soluble, recombinant IFN-gamma and 100-fold less than doses which induced adverse systemic effects. The mechanism by which ARC-encapsulation increased IFN-gamma activity in vivo remains uncertain. However, our in vitro results show that sustained release of soluble IFN-gamma is a likely factor. The ARC production and delivery system achieves enhanced adjuvant activity with reduced risk of systemic effects, and the low cost of IFN-gamma production offers new opportunities for the use of this important cytokine.
重组荧光假单胞菌细胞表达超过40%的蛋白质为牛γ干扰素（IFN-γ），经化学固定以对培养物进行灭菌并修饰细菌细胞壁。当对经杀死和固定的重组细胞（在此称为修饰重组细胞，即ARC）进行干扰素活性检测时，我们获得了以下惊人结果：1）灭菌和固定并未使ARC包封的IFN-γ失活；2）ARC包封的IFN-γ和可溶性重组IFN-γ在体外活性相同，但ARC细胞因子的释放需要蛋白水解作用；3）ARC包封的IFN-γ在体内具有活性，其最佳佐剂活性的剂量比先前报道的可溶性重组IFN-γ低约1000倍，比诱导全身不良反应的剂量低100倍。ARC包封增加IFN-γ体内活性的机制尚不确定。然而，我们的体外结果表明，可溶性IFN-γ的持续释放可能是一个因素。ARC生产和递送系统实现了增强的佐剂活性，同时降低了全身效应的风险，并且IFN-γ生产的低成本为使用这种重要细胞因子提供了新的机会。
