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Prevention of Candida biofilms by localized delivery of aurein analogues

通过局部递送金黄色素类似物预防念珠菌生物膜

基本信息

批准号：
9813824
负责人：
Sean P Palecek
金额：
$ 45.16万
依托单位：
UNIVERSITY OF WISCONSIN-MADISON
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-12-01 至 2021-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9813824
关键词：
Adaptive Immune System Address Adopted Affect Amino Acid Sequence Amino Acids Antibiotics Antifungal Agents Antimicrobial Cationic Peptides Antimicrobial Resistance Biological Assay Candida Candida albicans Catheters Cations Cell Wall Cell membrane Cells Cellular Structures Charge Collaborations Development Device or Instrument Development Devices Disseminated candidiasis Drug Delivery Systems Drug resistance Drug usage Effectiveness Electrostatics Engineering Environment Exhibits Face Film Fungal Components Goals Human Hydrophobic Interactions Hydrophobicity In Vitro Incidence Infection Lead Mammalian Cell Mediating Medical Device Membrane Microbe Microbial Biofilms Minimum Inhibitory Concentration measurement Modeling Molecular Nosocomial Infections Organism Pathogenicity Pattern Peptide Synthesis Peptides Periodicity Pharmaceutical Preparations Pharmacotherapy Phase Physiological Polymers Predisposition Prevention Prevention strategy Proteolysis Rana Rattus Recording of previous events Research Research Personnel Resistance Resistant candida Side Specificity Structure Surface Therapeutic Therapeutic Index Toxic effect Venous Work amphiphilicity analog antimicrobial peptide base candida biofilm candidemia cytotoxicity design drug development drug structure in vitro Model in vivo in vivo Model microbial mimetics mortality natural antimicrobial novel strategies pathogenic fungus pathogenic microbe peptide B peptide analog peptidomimetics prevent protein aminoacid sequence resistant strain side effect success virtual

项目摘要

ABSTRACT Candida spp. are the most common fungal pathogens isolated from humans and are leading causes of hospital-acquired infections, largely due to colonization of indwelling medical devices including catheters. Current strategies to prevent Candida spp. infections associated with medical devices include systemic antifungals, but these drugs suffer from severe toxicity and side effects, and drug-resistant strains have emerged. The goal of our project is to develop a novel strategy to prevent C. albicans biofilm formation on catheters by designing a new antifungal drug structurally templated on the natural broad-spectrum antimicrobial peptide (AMP) aurein 1.2. Like many AMPs, aurein 1.2 adopts a helical structure and selectively permeabilizes microbial membranes via cationic and hydrophobic interactions. However, efforts to develop AMPs into drugs have been largely unsuccessful since these compounds possess low stability in physiologic environments. Here, we propose to synthesize α/β-peptide aurein 1.2 mimetics which exhibit folding patterns that present side chains in virtually identical manner to native AMPs, and thus allow the use of α/β-peptide analogues templated on native antimicrobial peptide sequences as lead compounds. α/β-peptides are much more structurally stable than native antimicrobial peptides and are resistant to proteolytic degradation, offering significant advantages for drug development. Furthermore, we propose to develop a strategy to release this drug from catheter surfaces, localizing the treatment to inhibit biofilm formation. In prior work the PI identified that cationic, amphiphilic oligomers of β-amino acids (called β-peptides) can exhibit high levels of specific activity against C. albicans as compared to mammalian cells, although efforts reached a limit of potency and specificity. Collaborations with co-investigators on this project demonstrated sustained release from catheter surfaces and inhibition of biofilm formation in vitro and in vivo. Here, we will extend our findings and approach to α/β-peptides which are composed of both α− and β-amino acids. In the first two years of this project (R21 phase) we will generate α/β-aurein analogues and determine how varying hydrophobicity, net charge, and helical stability affect activity against drug-resistant C. albicans and specificity for C. albicans vs. mammalian cells. Then we will assess whether release of these compounds from polyelectrolyte multilayer (PEM) polymer films on a catheter surface inhibits C. albicans biofilm formation in vitro and in vivo. The remainder of the project (R33 phase) will further vary α- and β-amino acid sequence and combine features of α/β-aurein analogues identified to affect activity and specificity in C. albicans to optimize broad-spectrum antifungal activity and specificity in additional pathogenic Candida spp. Finally, we will develop polymer film-mediated release of the α/β-aurein analogues for sustained inhibition of Candida spp. biofilms in an in vitro model and then evaluate effectiveness of biofilm prevention in a rat model of central venous catheter infections. Together, these results will develop a novel strategy for prevention of device-associated candidemia.

摘要假丝酵母菌是从人类身上分离出来的最常见的真菌病原体，是导致医院获得性感染，主要是由于包括导管在内的留置医疗设备的殖民。目前预防假丝酵母菌的策略。与医疗器械相关的感染包括系统性感染抗真菌药物，但这些药物具有严重的毒性和副作用，而且耐药菌株出现了。我们项目的目标是开发一种新的策略来防止白色念珠菌生物被膜的形成。通过设计一种以天然广谱为结构模板的新型抗真菌药物抗菌肽(AMP)金黄色1.2。像许多AMP一样，Aurein 1.2采用螺旋结构并选择性地通过阳离子和疏水相互作用渗透微生物膜。然而，努力发展由于AMP化合物在生理上的稳定性较低，因此将其转化为药物在很大程度上是不成功的环境。在这里，我们建议合成呈现折叠图案的α/β-多肽Aurein1.2模拟物以与天然AMP几乎相同的方式呈现侧链，从而允许使用α/β-肽以天然抗菌肽序列为模板的类似物作为先导化合物。α/β-多肽很多在结构上比天然抗菌肽更稳定，并能抵抗蛋白质降解，提供药品研发优势显著。此外，我们建议制定一项战略，以释放这一点来自导管表面的药物，局部治疗以抑制生物被膜的形成。在之前的工作中，PI确定了 β-氨基酸的阳离子、两亲性低聚物(称为β-肽)可以表现出高水平的特异性与哺乳动物细胞相比，对白色念珠菌的活性，尽管努力达到了效力和专一性。在这个项目上与合作研究人员的合作证明了导管的持续释放体外和体内生物膜形成的表面和抑制。在这里，我们将扩展我们的发现和方法到α/β-肽，由α−和β-氨基酸组成。在该项目的前两年(R21 阶段)，我们将生成α/β-Arein类似物，并确定变化的疏水性、净电荷和螺旋稳定性影响对耐药白色念珠菌的活性和对白色念珠菌与哺乳动物的特异性细胞。然后我们将评估这些化合物是否从聚电解质多层(PEM)聚合物中释放导管表面的膜在体外和体内都能抑制白色念珠菌生物膜的形成。的其余部分项目(R33阶段)将进一步改变α-和β-氨基酸序列，并结合α/β-Arein的特征影响白色念珠菌活性和特异性的类似物优化广谱抗真菌药物附加致病念珠菌的活性和特异性。最后，我们将开发聚合物薄膜介体释放α/β-金黄色类似物对念珠菌的持续抑制作用。体外模型中的生物膜和然后在中心静脉导管感染的大鼠模型中评估生物被膜预防的有效性。一起，这些结果将开发一种预防设备相关性念珠菌血症的新策略。