Ultrasound-Assisted Gene Transfer of Anti-Biofilm Peptides to the Salivary Gland

描述（由申请人提供）：本提案将优化和应用一种非病毒基因转移到唾液腺的方法。该方法利用低频超声脉冲破坏微泡，引起局部空化，在细胞膜上打开瞬时孔隙，使非病毒载体进入唾液腺细胞。该方法源自现有的超声辅助基因转移（UAGT）技术，我们的研究小组最近表明，这种技术能够稳健、稳定、持久地将基因转移到唾液腺。与其他基因转移方法相比，UAGT有几个重要的优势，特别是假定缺乏免疫原性，因此理论上可以选择重新给药。基因转移到唾液腺提供了实现内源性生产和唾液分泌肽治疗的机会。内源性生产克服了许多挑战，这些挑战迄今为止限制了新兴的抗生物膜肽分子用于靶向牙周菌群中的单个不良分子。这些限制中最主要的是治疗药物本身的制造、稳定性和递送，以及在唾液中实现治疗药物的稳定、持续浓度的挑战。因此，本研究的长期目标是为UAGT在口腔医学中的应用奠定临床前基础。为了实现这一目标，我们将首先将已知的UAGT应用于唾液腺，并对该技术对唾液腺结构和活力的影响进行仔细的组织病理学评估。其次，我们将努力进行初步的原理验证研究，其中我们将在模型微生物（变形链球菌和铜绿假单胞菌）中引入具有已知抗生物膜活性的基因到唾液腺中，并在体外测定治疗动物产生的唾液的生物膜抑制特性。一旦这项技术在啮齿动物模型中被证明是可靠、安全和有效的，我们推测它可能是一种有吸引力的辅助剂，甚至是处理牙周组织中破坏性微生物病原体的主要方法，特别是在身体上无法进行常规口腔卫生的脆弱患者中。

DESCRIPTION (provided by applicant): The present proposal will optimize and apply a method for non-viral gene transfer to the salivary glands. This method utilizes low frequency ultrasound pulses to destroy microbubbles, causing local cavitation and opening transient pores in cell membranes enabling non-viral vectors to enter cells of the salivary gland. This proposed method is derived from existing ultrasound-assisted gene transfer (UAGT) techniques that our group has recently shown is capable of robust, stable, and long-lasting gene transfer to the salivary glands. UAGT has several important advantages over other gene transfer methods, in particular a presumed lack of immunogenicity and therefore the theoretical option to re-dose. Gene transfer to the salivary glands presents the opportunity to achieve endogenous production and salivary secretion of peptide therapeutics. Endogenous production overcomes many of the challenges that have thus far limited the utility of emerging anti-biofilm peptide molecules for targeting individual bad actors in the periodontal flora. Chief among these limitations are manufacturing, stability and delivery of the therapeutics itself, as well as the challenge of achieving a steady-state, sustained concentration of the therapeutic in the saliva. The long-term goal of this research therefore is to lay the pre-clinical groundwork for UAGT to the salivary glands for application in dental medicine. In order to achieve this goal, we will first apply what is already known regarding UAGT to the salivary gland and undertake a careful histopathological evaluation of the effect of this technique on salivary gland architecture and viability. Secondly, we will endeavor an initial proof-of-principle study wherein we will introduce genes with known anti-biofilm activity in model microorganisms (S. mutans and P. aeruginosa) to the salivary glands and assay in vitro the biofilm-inhibiting properties of saliva produced by treated animals. Once this technology has been proven to be reliable, safe and effective in the rodent model, we speculate that it may be an attractive adjuvant or even a primary approach to dealing with destructive microbial pathogens in the periodontium, particularly in vulnerable patients physically incapable of routine oral hygiene. PUBLIC HEALTH RELEVANCE: In this application, we propose to use a non-viral gene therapy approach to address the public health issue of chronic periodontal inflammation and tissue destruction by a subset of oral flora. Specifically, we propose a method of inhibiting biofilm formation, a natural process that is accelerated in the most vulnerable to of dental patients who are unable to maintain routine oral hygiene (i.e. tooth brushing). The immediate application of this technology to public health is to provide a gene therapy-based treatment that may bridge vulnerable patients between episodic periodontal treatments.