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产生了巨大的社会成本，估计为数十亿美元。在易感患者中，感染诱导先天免疫系统的错误调节，可最终导致全身炎症、严重疾病和死亡。开发具有抑制或调节这种反应能力的益生菌将具有巨大的价值和众多的医学应用。Scarab Genomics开发了Clean Genome（r）E。大肠杆菌菌株缺乏所有有害的基因序列，并且比哺乳动物系统中现有的菌株耐受性更好。这种降低的E.大肠杆菌菌株可以提供针对致命剂量的感染细菌以及小鼠毒素的立即保护，大概是通过抑制极端炎症反应，或通过提高先天免疫系统的准备水平，或两者兼而有之。这种保护作用在临床人群中具有很大的应用潜力，既可作为严重感染（包括脓毒症和脓毒性休克）的干预措施，也可作为预防措施，减少高危患者的感染机会。理想情况下，治疗将提供针对任何病原体挑战的普遍保护。在该提案的第一阶段，将检查可行性参数，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2阶段，将评价含有膜脂多糖（与先天免疫激活密切相关的细菌组分）改变的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。为了建立临床相关性，将使用小鼠模型来证明致死剂量的致病性大肠杆菌的Clean Genome（r）菌株的保护作用。大肠杆菌菌株，包括O 157：H7，一种定殖的、产滋贺毒素的菌株。将在此背景下测试的另一种保护性菌株是E.大肠杆菌菌株Nissle 1917，其已经作为益生菌使用了几十年，并且具有定殖肠道的能力。Nissle 1917目前正在进行基因组减少删除圣甲虫，已针对提高其安全性和稳定性。Nissle 1917作为抗感染和败血症的益生菌的开发将导致用于口服递送的保护性定殖细菌。我们的核心竞争力在有针对性的减少和改造E。大肠杆菌将使我们能够开发用于治疗感染和败血症的益生菌。 公共卫生相关性：这些Clean Genome（r）产品对人类健康的影响可能非常显著，减少了与手术或抗生素治疗相关的并发症。保护很可能延伸到许多其他细菌和病毒，提供先天保护，防止脓毒性和/或改善其病理，从而大大节省医疗保健费用。此外，开发成本将比传统药物低得多，清洁细菌的药物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.