Engineer bifunctional antibacterial enzymes for treatment of S. aureus infections

设计双功能抗菌酶来治疗金黄色葡萄球菌感染

• 批准号: 9301389
• 负责人: Karl E Griswold
• 金额: $ 16.2万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-20 至 2019-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9301389
• 关键词: Address; Algorithms; Anti-Bacterial Agents; Antibiotic Resistance; Antibiotics; Antibodies; Antigen-Antibody Complex; Bacteria; Bacterial Infections; Bacteriophages; Binding; Biological Response Modifier Therapy; Bispecific Antibodies; Blood; Blood Circulation; Catalytic Domain; Cause of Death; Cell Wall; Centers for Disease Control and Prevention (U.S.); Cessation of life; Chimera organism; Chimeric Proteins; Clinic; Clinical; Communities; Cytolysis; Dangerousness; Development; Dose; Drug Costs; Drug resistance; Drug-sensitive; Economics; Endopeptidases; Engineering; Enzymes; Exhibits; Eye Infections; Fc Immunoglobulins; Fc domain; Filtration; Frequencies; Genes; Genus staphylococcus; Half-Life; Healthcare Systems; Hospitalization; Hospitals; Human; Hydrolase; Immune response; Immunoglobulin G; Immunologic Surveillance; In Vitro; Incidence; Infection; Kidney; Lung; Lysostaphin; LytA enzyme; Medical; Methicillin Resistance; Molecular; Multi-Drug Resistance; Mutation; Patients; Peptidoglycan; Performance; Phenotype; Prophages; Protein Engineering; Proteins; Radial; Recombinants; Recording of previous events; Recycling; Resistance; Resistance development; Risk; Skin; Staphylococcus aureus; Stream; T-Lymphocyte Epitopes; Technology; Testing; Therapeutic; Toxic effect; Treatment outcome; Ursidae Family; Variant; antibody engineering; bacterial resistance; bactericide; bacteriocin; base; chemotherapy; clinical translation; combat; cost; dalton; design and construction; drug development; drug discovery; drug resistant bacteria; endolysin; enzyme therapy; experience; glomerular filtration; immunogenic; immunogenicity; improved; innovation; killings; lysin; methicillin resistant Staphylococcus aureus; neonatal Fc receptor; next generation; nonhuman primate; pathogen; resistant strain; scaffold; small molecule; synergism; therapeutic candidate

Abstract: Antibiotic resistance complicates the majority of Staphylococcus aureus (S. aureus) infections. A full two thirds of hospital-associated S. aureus infections and ~50% of those acquired in the community are now methicillin-resistant (MRSA). MRSA causes >450,000 infections in the US each year, and it is responsible for half of all deaths caused by drug-resistant bacteria. The high incidence of multi-drug resistance in S. aureus and other bacteria underscores the need for next-generation antibiotics capable of combating these dangerous pathogens. An increasingly compelling therapeutic strategy leverages recombinant enzymes, such as Staphylococcus simulans lysostaphin (LST), which degrade cell wall peptidoglycan causing bacterial lysis and death. LST is a highly potent anti-staphylococcal agent with proven efficacy against both drug-sensitive and drug-resistant strains of S. aureus. While LST holds great potential for combatting dangerous S. aureus infections, its utility as a systemically administered treatment is constrained by specific limitations. First, as a small protein of 26,942 daltons, LST is rapidly cleared from the blood stream by renal filtration. In the clinic, this fact might necessitate frequent, high dosing to achieve complete bacterial clearance. Providing the option to use lower doses and less frequent administration would reduce costs, ease patient burden, and improve treatment outcomes. Second, LST is subject to development of S. aureus resistance by virtue of mutations in the femA gene, which alters the specific peptidoglycan bond targeted by the enzyme. Synergistic 2-agent treatments have been shown to mitigate the risk of LST resistance. We propose here to construct a modular bifunctional lysin platform based on fusions with immunoglobulin Fc domains. The Fc domain is a natural bivalent display scaffold, and we aim to leverage validated knob and hole bispecific Fc engineering strategies to create heterobifunctional Fc-lysin chimeras. Specifically, we will fuse the LST catalytic and cell wall binding domains to one chain of a heterodimeric knob and hole Fc, and we will fuse the SA2 prophage endopeptidase domain to the second chain. The heterologous pairing of the two Fc chains will create a single molecular entity that integrates two complementary cell wall hydrolases known to exert anti-S. aureus synergy. The bifunctional Fc-lysin's two pronged attack on S. aureus cell walls should minimize acquired resistance. Additionally, the Fc domain will serve to extend the bifunctional lysin's circulation half-life by (i) increasing the molecule's size beyond the limit for first-pass glomerular filtration in the kidney, and (ii) engaging the neonatal Fc receptor (FcRn), which actively recycles IgG antibodies and promotes their exceptionally long half-lives. As a whole, this project seeks to develop a modular platform for engineering high performance antibacterial enzymes that capitalize on intramolecular synergy to kill drug-resistant bacterial pathogens.

摘要：抗生素耐药性使大多数金黄色葡萄球菌（金黄色葡萄球菌）感染复杂化。一个完整的 现在，与医院相关的金黄色葡萄球菌感染的三分之二，而在社区中获得的链球菌感染中有约50％ 耐甲氧西林（MRSA）。 MRSA每年在美国引起> 450,000次感染，并负责 一半是由耐药细菌造成的所有死亡。金黄色葡萄球菌中多药抗性的高发病率 其他细菌强调了能够与这些危险作斗争的下一代抗生素的需求 病原体。越来越令人信服的理论策略利用重组酶，例如 葡萄球菌lysostaphin（LST），降解细胞壁辣椒粉，引起细菌裂解和 死亡。 LST是一种高潜在的抗稳定球菌剂，对药物敏感和 金黄色葡萄球菌的抗药性菌株。虽然LST拥有对抗危险的金黄色葡萄球菌的巨大潜力 感染，其作为系统给予的治疗的效用受到特定限制的限制。首先，作为 LST的小蛋白质为26,942 daltons，通过肾脏过滤从血液中迅速清除。在诊所中，这个 事实可能需要经常需要高剂量才能实现完全的细菌清除率。提供选项 使用较低的剂量和较少的管理会降低成本，减轻患者的伯恩伯恩并改善 治疗结果。其次，LST因突变而受到金黄色葡萄球菌抗性的发展 FEMA基因，它改变了由酶靶向的特定的胡椒糖键。协同2代理 已经证明治疗可减轻LST抗性的风险。我们在这里建议构建一个模块化 基于与免疫球蛋白FC结构域的融合的双功能赖氨酸平台。 FC域是自然的 二价展示脚手架，我们的目标是利用经过验证的旋钮和双孔双特异性足球工程策略 创建异常功能的FC-Lysin Chimeras。具体而言，我们将融合LST催化和细胞壁结合 域链和孔FC的一个链，我们将融合SA2PREPAGE内肽酶 第二链的域。两个FC链的异源配对将创建一个分子实体 这整合了已知施加抗S的两个完整的细胞壁水解酶。金黄色协同作用。双功能 FC-Lysin对金黄色葡萄球菌细胞壁的两次抬头攻击应最大程度地减少获得的抗性。此外，FC 域将通过（i）增加分子的大小来延长双功能赖氨酸的循环半衰期 超出了肾脏中第一通通肾小球过滤的极限，（ii）与新生儿FC接收器互动 （FCRN），积极回收IgG抗体并促进其异常长的半衰期。总体而言，这个 项目旨在开发一个模块化平台，用于工程高性能抗菌酶 利用分子内协同作用，以杀死耐药细菌病原体。