Erythrocyte-derived particles for near infrared phototherapy of port wine stains

 描述(申请人提供)：鲜红斑点(PWSS)是一种先天性和进行性皮肤毛细血管畸形。在组织病理学上，≈的特征是扩张的毛细血管，直径从大约10微米到PWS600微米不等，以及 通常位于皮肤表面以下300-500微米的≈深处。PWS是一种具有潜在破坏性心理和生理并发症的疾病，极大地损害了患者的生活质量。目前，唯一可行的治疗方法是基于激光照射，使用可见光波长，以热破坏异常的血管系统。然而，由于可见的激光照射参数不能达到不可逆转地破坏血管所需的临界核心温度，特别是在较深的皮肤部位(&gt；300微米)，因此可能的斑点对当前的激光治疗方法具有抵抗力，需要多次治疗才能实现完全褪色。此外，很大一部分中度到重度色素沉着的患者(中度棕色到黑色皮肤)由于覆盖表皮的非特异性加热而无法从激光治疗中受益。我们的最终目标是开发一种基于激光的方法，可以用于治疗耐药性斑点，以及所有PWS患者，无论他们的皮肤类型。我们提出的方法是基于使用由FDA批准的近红外(NIR)发色团组成的光学囊泡，吲哚青绿(ICG)由红细胞膜包裹。我们将这些小泡称为近红外类红血球传感器(NETs)。一旦被近红外激光照射激活，这些囊泡就会将光能转化为热量，导致血管的热破坏。我们将这种方法称为激光热疗(LET)。近红外激光照射的优点是，它允许光线更深地穿透皮肤，并减少由于黑素小体吸收减少而导致的非特异性表皮加热的风险。Net作为外源性发色团在血管内增强近红外吸收的潜在优势在于它们在血管内的潜在较长的循环时间，以延长可以进行LET的治疗窗口，以及它们预期的生物相容性。本申请的总体主题是在确定最佳ICG含量、直径和相对数量浓度的基础上，确定适当的Net配方，该ICG含量、直径和相对数量浓度将导致具有适当光学特性的最大血管保留时间，以及将导致深血管的最佳近红外照射参数 对表皮没有非特异性热损伤的损伤。为此，我们的方法将集中在不同配方的Net的物理特征，量化它们的光学特性，它们在健康小鼠中的生物分布，预测由于这些配方引起的近红外激光照射响应的光和温度分布的数学模型，以及最后涉及动物的兔耳垂血管的体内NIR激光照射研究 注射了这种网络配方的PWSS模型。我们还将评估这些制剂对小鼠的潜在毒性和免疫原性。在这个项目完成后，我们将确定合适的NET配方，并能够在申请后的下一个赠款期间使用这些信息来指导我们的人体实验研究。这项多PI应用程序将在加州大学河滨分校(UCR)生物工程教授巴赫曼·安瓦里博士和加州大学欧文分校(UCI)贝克曼激光研究所和医学诊所(BLIMC)医学主任J.S.Nelson博士的领导下进行。安瓦里博士将监督整个项目，并全面负责协调和管理该项目。蚊帐的制造和表征、生物分布、毒性和免疫原性研究将在他的监督下进行。他还将与纳尔逊博士的团队在光学性质的量化、数学模型的开发和体内动物激光照射研究方面密切合作。其他主要合作人员包括David Lo，MD，PhD(加州大学河滨分校)，他将在小鼠免疫原性研究的设计和结果评估方面提供专业知识；王存佳(加州大学欧文分校)，他将参与光学特性的量化、数学模型的开发以及兔的体内激光照射；Stephen Griffey，博士，DVM(加州大学戴维斯分校)，他将支持我们使用血液学特征、血清化学和组织病理学评估对蚊帐的毒性进行评估。

 DESCRIPTION (provided by applicant): Port wine stains (PWSs) are congenital and progressive malformations of dermal capillaries. Histopathologically, PWSs are characterized by ectatic capillaries with diameters that can range from about 10 µm to as large as ≈ 600 µm, and usually located in depths of ≈ 300-500 µm below the skin surface. PWS is a disease with potentially devastating psychological and physical complications that greatly impairs the quality of life for the afflicted individuals. Currently, the only viable treatment approach is based on laer irradiation, using visible wavelengths, to thermally destroy the abnormal vasculature. However, may stains are resistive to current laser treatment methods since the visible laser irradiation parameters do not achieve the critical core temperature necessary to irreversibly destroy blood vessels, particularly at the deeper skin locations (>300 µm), necessitating many therapeutic sessions to achieve complete fading, if at all. Furthermore, a large segment of patients with moderate to heavy pigmentation (moderate brown to black skin) cannot benefit from laser therapy due to non-specific heating of the overlying epidermis. Our ultimate objective is to develop a laser-based approach that can be used to treat resistive stains, and all patients with PWS regardless of their skin types. Our proposed approach is based on the use of optical vesicles composed of the FDA-approved near infrared (NIR) chromophore, indocyanine green (ICG), encapsulated by membranes derived from erythrocytes. We refer to these vesicles as near infrared erythrocyte-mimicking transducers (NETs). Once activated by NIR laser irradiation, these vesicles transduce the light energy to heat, leading to thermal destruction of blood vessels. We refer to this approach as laser- erythro-therapy (LET). The advantage of NIR laser irradiation is that it allows for deeper penetration of light into the skin, and reduces the isk of non-specific epidermal heating due to reduced absorption by melanosomes. The potential advantages of NETs as an exogenous chromophore to enhance NIR absorption within the blood vessels are in their potentially long circulation time within the vasculature to extend the therapeutic window of time during which LET can be performed, and their expected biocompatibility. The overall subject of this application is to determine the appropriate formulations of NETs, based on identifying the optimal ICG content, diameter, and relative number concentration, that will result in maximum vascular retention time with appropriate optical properties, as well as optimal NIR irradiation parameters that will result in deep vascular injury without non-specific thermal injury to the epidermis. To do so, our approach will be centered upon physical characterizations of various formulation of NETs, quantification of their optical properties, their biodistributions in healthy mice, mathematical models to predict light an temperature distributions in response to NIR laser irradiation due to these formulations, and finally in-vivo NIR laser irradiation studies involving the rabbit earlobe vasculature as an animal model of PWSs injected with such NETs formulations. We will also evaluate the potential toxicity and immunogenic effects of these formulations in mice. Upon completion of this project, we will have identified the appropriate formulations of NETs, and be in a position to use that information in guiding our human experimental studies in the next grant period following this application. This Multi-PI application will be performed under the leaderships of Dr. Bahman Anvari, Professor of Bioengineering at University of California, Riverside (UCR), and Dr. J. S. Nelson, Medical Director of the Beckman Laser Institute and Medical Clinic (BLIMC), University of California, Irvine (UCI). Dr. Anvari will oversee the entire project, and have overall responsibiliy to coordinate and administer the project. Fabrication and characterization of the NETs, biodistribution, toxicity, and immunogenicity studies will be performed under his supervision. He will also work closely with Dr. Nelson's group on quantification of the optical properties, development of mathematical models and in-vivo animal laser irradiation studies. Other key collaborating personnel are David Lo, MD, PhD (UC Riverside) who will provide the expertise in the design of the immunogenic studies in mice, and evaluating those results; Wangcun Jia, PhD (UC Irvine) who will be involved in quantification of optical properties, development of the mathematical models, and in vivo laser irradiation of the rabbits; and Stephen Griffey, PhD, DVM (UC Davis) who will support us in our toxicity evaluations of the NETs using hematological profiling, serum chemistry, and histopathological evaluations.