Innate Immune Protection by Clean Genome E. coli

描述(由申请人提供)：病原体感染引起的并发症在发病率和死亡率(高达50%-60%)以及护理和治疗方面都造成了巨大的社会成本，估计高达数十亿美元。在易受感染的患者中，感染会导致先天免疫系统的失调，最终导致全身炎症、严重疾病和死亡。开发能够抑制或调节这种反应的益生菌将具有巨大的价值和众多的医学应用。圣甲虫基因组公司已经开发出不含所有有害基因序列的清洁基因组(R)大肠杆菌菌株，并且比哺乳动物系统中现有的菌株具有更好的耐受性。这种减少的大肠杆菌菌株可以立即对小鼠体内致命剂量的感染细菌和毒素提供保护，可能是通过抑制极端的炎症反应，或者通过提高先天免疫系统的准备水平，或者两者兼而有之。这种保护作用在临床人群中具有巨大的潜力，既可以作为对包括败血症和感染性休克在内的严重感染的干预，也可以作为预防措施，以减少高危患者的感染机会。理想情况下，这种治疗将提供针对任何病原挑战的普遍保护。在建议的第一阶段，将审查可行性参数，包括给药方案、给药途径和非活性制剂预防脓毒症的能力。在第二阶段，将评估含有膜脂多糖(与天然免疫激活强烈相关的细菌成分)变化的Clean Genome(R)菌株对脓毒症的保护作用。此外，我们将确定减少基因组菌株的保护是否延伸到其他革兰氏阴性细菌菌株。为了确定临床相关性，将使用小鼠模型来演示Clean Genome(R)菌株对致病大肠杆菌菌株的致死剂量的保护作用，包括O157：H7，一种定植的志贺毒素产生菌株。将在这方面进行测试的另一种保护性菌株是大肠杆菌Nissle 1917，它作为益生菌已经使用了几十年，具有在肠道定植的能力。Nissle 1917目前正在Scarab进行基因组减少删除，目的是增强其安全性和稳定性。Nissle 1917作为一种抗感染和败血症的益生菌的开发将导致保护性定植细菌用于口腔递送。我们在定向减少和修饰大肠杆菌方面的核心能力将使我们能够开发用于治疗感染和败血症的益生菌。 与公共健康相关：这些Clean Genome(R)产品对人类健康的影响可能非常显著，可以减少与手术或抗生素治疗相关的并发症。保护可能延伸到许多其他细菌和病毒，提供针对败血症毒性的先天保护和/或改善它们的病理，从而大幅节省医疗保健成本。此外，开发成本将比传统药物低得多，清洁细菌的制药生产将是经济和高效的。

DESCRIPTION (provided by applicant): Complications arising from pathogen infection incur a tremendous societal cost both in morbidity and mortality (as high as 50-60%), as well as in care and treatment estimated in billions of dollars. In susceptible patients, infection induces mis-regulation of the innate immune system that can culminate in systemic inflammation, severe illness and death. The development of probiotics with the capacity to dampen or modulate this response would have enormous value and numerous medical applications. Scarab Genomics has developed Clean Genome(r) E. coli strains that are devoid of all deleterious gene sequences and are tolerated better than existing strains in mammalian systems. Such reduced E. coli strains can provide immediate protection against a lethal dose of infecting bacteria as well as toxins in mice, presumably by suppressing the extreme inflammatory response, or by raising the level of preparedness of the innate immune system, or both. This protective effect has great potential for use in clinical populations, both as an intervention for serious infections including sepsis and septic shock, and as a prophylactic to reduce the chance of infection in at-risk patients. Ideally the treatment would provide universal protection against any pathogenic challenge. In Phase I of the proposal, feasibility parameters including dosing regimen, route of delivery and the ability of non-viable preparations to protect against sepsis will be examined. In Phase 2, Clean Genome(r) strains that contain alterations in membrane lipopolysaccharide (the bacterial component strongly associated with innate immune activation) will be evaluated for protection against sepsis. Further, we will determine whether protection by reduced genome strains extends to other Gram-negative bacterial strains. To establish clinical relevance, a mouse model will be used to demonstrate protection by Clean Genome(r) strains of lethal doses of pathogenic E. coli strains including O157:H7, a colonizing, Shiga toxin-producing strain. An additional protective strain that will be tested in this context is the E. coli strain Nissle 1917, which has been in use as a probiotic for many decades and which has the capacity of colonize the intestine. Nissle 1917 is currently undergoing genome- reducing deletions at Scarab that have been targeted to enhance its safety and stability. The development of Nissle 1917 as a probiotic against infection and sepsis will result in protective colonizing bacteria for oral delivery. Our core competence in the targeted reduction and modification of E. coli will enable us to develop probiotics for the treatment of infection and sepsis. PUBLIC HEALTH RELEVANCE: The impact of these Clean Genome(r) products on human health could be highly significant, reducing complications associated with surgery or antibiotic treatments. Protection is likely to extend to many other bacteria and viruses, providing innate protection against septic toxicity and/or ameliorating their pathology, resulting in substantial savings in health care costs. Further, development costs would be much lower than for conventional drugs, and pharmaceutical production of clean bacteria would be economical and highly efficient.