Near-infrared laser to replace chemical vaccine adjuvant

描述(申请人提供)：这项建议探索了无组织损伤的连续波(CW)近红外(NIR)激光增强适应性免疫反应的细胞和分子机制，并开发了一种安全有效的皮肤和粘膜疫苗免疫佐剂。这样做的最终目的是取代同时使用的化学或生物疫苗佐剂。虽然免疫佐剂对于目前的疫苗通常是必不可少的，但许多获得许可的和开发阶段的佐剂会产生显著的副作用。这就需要开发新的安全有效的佐剂。以前已经证明，用纳秒脉冲波(PW)可见光照射皮肤可以增强人类和小鼠对疫苗接种的免疫反应。然而，这些激光需要联合使用另一种化学佐剂来诱导充分增强的免疫反应。此外，绿色或黄色光谱中的激光被黑色素吸收，导致不同皮肤照片类型的光吸收高度不同，从而限制了其临床应用。我们首次证明，在不使用任何额外试剂的情况下，对皮肤小区域进行短时间曝光的非组织破坏性近红外激光可以增加对流感抗原的广泛免疫反应。这发生在与授权佐剂相当的程度上，并导致在致死挑战小鼠模型中提高存活率。使用低功率的CW近红外激光器比PW可见光激光器以及获得许可的化学疫苗佐剂有几个优势。由于水是近红外激光的主要发色团，不同皮肤的光吸收没有明显的变化。激光降低了潜在的佐剂反应性和毒性，因为它不会诱导长期的炎症细胞因子反应，不会促进过敏性，而且与化学佐剂不同，它不会在暴露的组织中持续存在。由于激光位于疫苗的外部，它不会像传统疫苗-化学佐剂组合那样造成任何稳定性问题。这些具有挑衅性的发现提出了我们将在这项建议中解决的下列三个重要领域的进一步研究：1)利用已建立的小鼠和雪貂流感感染动物模型，探讨皮肤中的近红外激光是否能增强对以皮肤为基础的流感疫苗的长期免疫应答；2)阐明近红外激光佐剂在体外和体内的细胞学和分子作用机制；以及3)探索这项技术在小鼠和雪貂黏膜疫苗接种中的应用。在这项提议达到顶峰后，我们的目标是证明近红外激光佐剂在皮肤和粘膜疫苗接种方面的有效性和作用机制。这一发现的可译性因目前成熟、安全、紧凑和相对简单的低瓦数连续波近红外激光技术的可获得性而得到增强，从而有可能经济地生产一种便携式(手持)低成本设备，在足够的疫苗接种量下，可以取代化学佐剂。这种设备可能会对当前的临床实践产生立竿见影的巨大影响。

DESCRIPTION (provided by applicant): This proposal explores the cellular and molecular mechanisms of a non-tissue damaging continuous wave (CW) near-infrared (NIR) laser to enhance adaptive immune responses, and develops a safe and effective immunologic adjuvant for skin and mucosal vaccination. The ultimate purpose of this is to replace a concurrent chemical or biological vaccine adjuvant. Although immunologic adjuvants are often essential for current vaccines, many licensed and development-stage adjuvants cause significant side effects. This necessitates the development of new safe and effective adjuvants. Illumination of the skin with nanosecond-pulsed wave (PW) visible range laser light has previously been shown to enhance immune responses to vaccination in humans and mice. However, these lasers require co-administration of an additional chemical adjuvant to induce a sufficiently increased immunological response. In addition, laser light in the green or yellow spectrums is absorbed by melanin, resulting in highly variable light absorption across different skin phototypes and therefore limiting its clinical utility. We have shown, for the first time, that that non-tissue damaging NIR laser light given in short exposures to small areas of the skin, without the use of any additional agents, increases a broad spectrum of immune responses to influenza antigen. This occurs at a magnitude comparable to licensed adjuvants, and results in improved survival in a lethal challenge murine model. Use of a low-power CW NIR laser has several advantages over PW visible light lasers, as well as licensed chemical vaccine adjuvants. Since water is the predominant chromophore for NIR laser light, light absorption is not significantly altered across different skin phototypes. The laser reduces potential adjuvant reactogenicity and toxicity, as it does not induce a prolonged inflammatory cytokine response, does not promote allergenicity, and unlike chemical adjuvants, does not persist in exposed tissues. Since the laser is external to a vaccine it does not pose any stability issues that conventional vaccine-chemical adjuvant combinations do. These provocative findings raise the following three important areas for further investigation that we will address in this proposal: 1) To explore whether NIR laser light in the skin enhances a long-term recall immune response to skin-based influenza vaccination using established animal models of influenza infection in mice and ferrets, 2) Elucidation of the cellula and molecular mechanisms of action of the NIR laser adjuvant in vitro and in vivo, and 3) Exploration of the use of this technology in mucosal vaccinations in mice and ferrets. Upon the culmination of this proposal, we aim to demonstrate the efficacy and mechanisms of action of the NIR laser adjuvant in the context of skin and mucosal vaccination. The translatability of this discovery is enhanced by the current availability of mature, safe, compact and relatively simple low-wattage CW NIR laser technology, making it possible to economically produce a portable (handheld) low cost device that, at sufficient vaccination volumes, could replace chemical adjuvants. Such a device could have an immediate and tremendous impact on current clinical practice.