Innate Immune Stimulation as a Pathogen Countermeasure

描述（由申请人提供）：本项目的总体目的是研究和开发一种新型免疫刺激剂，可用于引发针对可能用于生物恐怖袭击的病原微生物的非特异性保护。该产品由阳离子脂质体-质粒DNA复合物（CLDC）组成，是一种非常有效的激活先天免疫的刺激物，特别是用于释放干扰素和其他细胞因子。CLDC相对于常规免疫刺激剂的主要优点是它们是更有效的干扰素释放激活剂，它们可以通过气雾剂或粘膜递送施用，它们可以冻干并保留活性，并且它们的制造相对简单和便宜。拟定研究旨在检验CLDC可快速引发足够的保护性先天免疫的假设，以在气溶胶细菌攻毒啮齿动物模型中在胃肠外或粘膜后有效。在初步研究中，我们观察到CLDC给药后先天免疫的有效激活和结核分枝杆菌气雾剂攻击后的疗效。在用土拉弗朗西斯菌LVS进行致死性鼻内攻毒前48小时，腹膜内和鼻内给予CLDC后也观察到完全保护作用。因此，我们将检查通过其他给药途径CLDC介导的免疫激活的有效性，特别是在粘膜递送至肺和上呼吸道后，以评价对致病性更高的F.土拉菌4.本项目的具体目标是（1）确定CLDC的给药途径和给药方案如何影响先天免疫激活的幅度、质量和持续时间，以及（2）确定CLDC诱导的免疫对抗F.土拉菌挑战。我们相信这些研究将为CLDC以易于管理的形式快速激活有效和一致的先天免疫反应的能力提供基础，这在生物防御和民用应用中至关重要。

DESCRIPTION (provided by applicant): The overall purpose of this project is to investigate and develop a novel immune stimulant that can be used to elicit non-specific protection against pathogenic microorganisms that might be deployed in bioterrorist attacks. The product, comprised of cationic liposome-plasmid DNA complexes (CLDC), is an extremely potent stimulus for activation of innate immunity, particularly for release of interferons and other cytokines. The major advantages of CLDC relative to conventional immunostimulants are that they are more potent activators of interferon release, they can be administered by aerosol or mucosal delivery, they can be lyophilized and retain activity, and they are relatively simple and inexpensive to manufacture. The proposed studies are designed to test the hypothesis that CLDC can rapidly elicit sufficient protective innate immunity to be efficacious after parenteral or mucosal in an aerosol bacterial challenge rodent model. In preliminary studies, we have observed potent activation of innate immunity after administration of CLDC and efficacy after aerosol challenge with Mycobacterium tuberculosis. Complete protection has also been observed following intraperitoneal and intranasal administration of CLDC 48 hours prior to lethal intranasal challenge with Francisella tularensis LVS. We will, therefore, examine the effectiveness of CLDC-mediated immune activation by other routes of administration, particularly after mucosal delivery to the lungs and upper airways to evaluate protection against aerosol challenge with the more pathogenic F. tularensis Schu4. The specific goals of this project are (1) to determine how the route of administration and dosing regimen of CLDC affects the magnitude, quality, and duration of innate immune activation, and (2) determine the impact of CLDC-induced immunity on protection against F. tularensis challenge. We believe these studies will provide the basis for the CLDC's ability, in an easily administered format, to rapidly activate potent and consistent innate immune responses that will be essential in biodefense and civilian applications.