ISTAb- A novel therapy to target staphylococcal toxins at the site of infections

ISTAb - 一种针对感染部位葡萄球菌毒素的新型疗法

• 批准号: 9890989
• 负责人: Rajan P Adhikari
• 金额: $ 30万
• 依托单位: INTEGRATED BIOTHERAPEUTICS, INC.
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9890989
• 关键词: Advanced Development; Affinity; Air; Antibiotics; Antibodies; Antigen-Antibody Complex; Bacillus anthracis; Bacteria; Bacterial Infections; Bacterial Toxins; Bacteriophages; Binding; Biochemical; Bioinformatics; Biological Assay; Biophysics; Blood Circulation; Businesses; Capital; Cell Surface Proteins; Cell Wall; Cells; Cessation of life; Clinical; Clinical Trials; Clostridium difficile; Complex; Computer-Aided Design; Data; Diphtheria; Disease; Distant; Endocarditis; Engineering; Exotoxins; Failure; Generations; Genus staphylococcus; Grant; Growth; Hemolysin; Hospitalization; Immune; Immune Evasion; Immune response; Immunoglobulin G; Immunotherapeutic agent; Immunotherapy; In Vitro; Individual; Infection; Joint Prosthesis; Life; Lymphocyte; Lysostaphin; Mammalian Cell; Mediating; Microbial Biofilms; Modeling; Modification; Monoclonal Antibodies; Mus; Mutation; National Institute of Allergy and Infectious Disease; Organ; Oryctolagus cuniculus; Pathogenesis; Patients; Pertussis; Phagocytes; Pharmaceutical Preparations; Phase; Phase I Clinical Trials; Play; Pneumonia; Polysaccharides; Preventive; Property; Prophylactic treatment; Proteins; Recording of previous events; Resistance; Role; Sepsis; Site; Skin Tissue; Small Business Innovation Research Grant; Soft Tissue Infections; Species Specificity; Staphylococcal Infections; Staphylococcal Protein A; Staphylococcus aureus; Staphylococcus aureus infection; Structure; Superantigens; Superbug; Surface; Surface Antigens; Surgical Wound Infection; Technology; Testing; Tetanus Vaccine; Time; Tissues; Toxin; Toxoids; Treatment Efficacy; Vaccinated; Vaccines; Virulence Factors; Wound Infection; alpha Toxin; anthrax toxin; antitoxin; bacteriolysin; clinical development; commercialization; efficacy study; experience; experimental study; human monoclonal antibodies; human pathogen; immunopathology; improved; in vivo; in vivo evaluation; interest; joint infection; leukotoxin; macrophage; monocyte; mouse model; mutant; neutralizing monoclonal antibodies; neutrophil; new technology; novel; novel strategies; novel therapeutics; pathogen; pathogenic bacteria; pneumonia model; preclinical efficacy; prevent; product development; prototype; response; skin disorder; vaccine development; vaccine immunotherapy; ventilator-associated pneumonia

Project Summary Many bacterial pathogens secrete exotoxins to modify the host-pathogen interactions in a manner that benefits the bacteria. There are several examples of successful prophylaxis and treatment by targeting bacterial toxins as evident by decades-long history of vaccines for tetanus, diphtheria, and pertussis. Staphylococcus aureus (SA) is a major human pathogen responsible for several hundred thousand of hospitalizations and over 12,000 death in the US every year. SA produces a plethora of toxins including pore-forming toxins (PFTs) that play a key role in pathogenesis and immune evasion. While neutralization of these toxins by monoclonal antibodies (mAbs) is expected to reduce clinical disease, it is unlikely to uproot invasive disease, as suggested by recent failure of a PFT mAb cocktail to prevent SA ventilator associated pneumonia (Arsanis clinical trial). We have devised a novel approach to target neutralizing anti-toxin mAbs specifically to the site of infection enabling instant toxin neutralization and mediating opsonophagocytic killing (OPK) at the same time. The approach exploits the cell wall targeting domains (CWT) of a phage-derived bacteriolysin which binds with species-specificity and high affinity to cell wall components of specific bacteria. The CWT is fused to specific anti-toxin mAbs to generate Infection Site Targeted Antitoxin antibodies (ISTAbs). We have successfully applied this to B. anthracis and C. difficile under NIAID support. In this proposal we aim to develop ISTAbs for S. aureus using the isolated CWT of lysostaphin along with potent PFT neutralizing mAbs. ISTAbs are expected to accumulate where they are needed most, i.e. at the site of infection; they capture and sequester the toxins, thus immediately neutralizing the immune suppressive effects of the toxins and preventing their release into circulation. Bacterium-ISTAb-toxin complex is then cleared by phagocytes. Concurrent toxin neutralization and bacterial clearance is a unique advantage of the ISTAb technology over mere antitoxin treatment. In this proposal, we will use a set of broadly neutralizing S. aureus PFT mAbs to generate ISTAbs with lysostaphin CWT. However, because IgG binding to protein A on the surface of S. aureus interferes with opsonophagocytic killing and may even cause immunopathology, we will create and test mutant ISTAbs that do not bind protein A. In Aim 1, these ISTAbs will be generated and characterized for biophysical and functional properties, including neutralization and OPK activity, to select a short list for in vivo efficacy studies. In Aim 2, we will evaluate the efficacy of ISTAbs in different mouse models of S. aureus infection including pneumonia, sepsis and surgical wound infection. Upon completion of the Phase I SBIR we anticipate a Phase II project to expand the efficacy studies to invasive infection models in rabbits including sepsis, prosthetic joint infection, ventilator associated pneumonia, and endocarditis models as well as IND-enabling studies.

项目概要 许多细菌病原体会分泌外毒素，以有利于宿主与病原体的相互作用的方式改变宿主与病原体之间的相互作用。 细菌。有几个针对细菌毒素成功预防和治疗的例子 破伤风、白喉和百日咳疫苗数十年的历史就证明了这一点。金黄色葡萄球菌 (SA) 是一种主要的人类病原体，导致数十万人住院，超过 12,000 人死亡。 美国每年都有人死亡。 SA 产生大量毒素，其中包括成孔毒素 (PFT) 在发病机制和免疫逃避中发挥关键作用。当单克隆抗体中和这些毒素时 （单克隆抗体）有望减少临床疾病，但正如最近的研究表明，它不太可能根除侵袭性疾病 PFT mAb 混合物未能预防 SA 呼吸机相关性肺炎（Arsanis 临床试验）。我们有 设计了一种新方法，将中和抗毒素单克隆抗体专门针对感染部位，从而能够立即 同时中和毒素并介导调理吞噬杀伤（OPK）。该方法利用了 噬菌体来源的溶菌素的细胞壁靶向结构域（CWT），具有物种特异性和高结合力 对特定细菌的细胞壁成分的亲和力。 CWT 与特定的抗毒素单克隆抗体融合以生成 感染部位靶向抗毒素抗体 (ISTAb)。我们已成功地将其应用于炭疽杆菌和炭疽杆菌。 艰难梭菌在 NIAID 的支持下。在本提案中，我们的目标是使用分离的 CWT 开发金黄色葡萄球菌的 ISTAb 溶葡萄球菌素以及有效的 PFT 中和单克隆抗体。 ISTAb 预计会在其所在位置积聚 最需要的，即感染部位；它们捕获并隔离毒素，从而立即中和 毒素的免疫抑制作用并防止其释放到循环中。细菌-ISTAb-毒素 然后复合物被吞噬细胞清除。同时进行毒素中和和细菌清除是一种独特的方法 ISTAb 技术相对于单纯抗毒素治疗的优势。 在本提案中，我们将使用一组广泛中和金黄色葡萄球菌 PFT mAb 来生成 ISTAb 溶葡萄球菌素 CWT。然而，由于 IgG 与金黄色葡萄球菌表面的蛋白 A 结合，会干扰 调理吞噬细胞杀死甚至可能引起免疫病理学，我们将创建并测试突变的 ISTAbs 不结合蛋白 A。在目标 1 中，将生成这些 ISTAb，并对其生物物理和功能进行表征 性质，包括中和和 OPK 活性，以选择用于体内功效研究的简短列表。在目标 2 中， 我们将评估 ISTAb 在不同金黄色葡萄球菌感染小鼠模型中的功效，包括肺炎、 败血症和手术伤口感染。第一阶段 SBIR 完成后，我们预计第二阶段项目将 将功效研究扩展到兔子的侵袭性感染模型，包括脓毒症、假体关节感染、 呼吸机相关性肺炎和心内膜炎模型以及 IND 支持研究。

项目成果

Hyperimmune Targeting Staphylococcal Toxins Effectively Protect Against USA 300 MRSA Infection in Mouse Bacteremia and Pneumonia Models.

• DOI: 10.3389/fimmu.2022.893921
• 发表时间: 2022
• 期刊: Frontiers in immunology
• 影响因子: 7.3

Wall Teichoic Acids Facilitate the Release of Toxins from the Surface of Staphylococcus aureus.

• DOI: 10.1128/spectrum.01011-22
• 发表时间: 2022-08-31
• 期刊: MICROBIOLOGY SPECTRUM
• 影响因子: 3.7
• 作者: Brignoli, Tarcisio;Douglas, Edward;Duggan, Seana;Fagunloye, Olayemi Grace;Adhikari, Rajan;Aman, M. Javad;Masseya, Ruth C.
• 通讯作者: Masseya, Ruth C.