Safety assessments of tissue irradiation with near infrared fs pulses for multi-photon imaging applications

用于多光子成像应用的近红外飞秒脉冲组织照射的安全性评估

• 批准号: 10531610
• 负责人: IRENE GEORGAKOUDI
• 金额: $ 7.8万
• 依托单位: TUFTS UNIVERSITY MEDFORD
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-12-01 至 2024-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10531610
• 关键词: 3-Dimensional; Address; Adoption; Animals; Apoptosis; Architecture; Area; Biopsy; Brain; Cardiovascular Diseases; Cells; Cervical; Cervix Uteri; Characteristics; Contrast Media; DNA Damage; Databases; Dependence; Development; Diagnosis; Diagnostic; Disease; Dose; Early Diagnosis; Engineering; Ensure; Epithelium; Evaluation; Eye; Fibrosis; Freezing; Genomics; Goals; Hamsters; Health; Histology; Human; Human Engineering; Image; Immunofluorescence Immunologic; In Vitro; Label; Lasers; Light; Lighting; Malignant Neoplasms; Medical center; Metabolic; Methods; Modality; Modeling; Monitor; Morphology; Motivation; Nature; Obesity; Optics; Oral; Organ; Photons; Physiologic pulse; Proliferating; Proteomics; Protocols documentation; Reporting; Reproducibility; Resolution; Safety; Sampling; Skin; Source; Specimen; Spottings; Squamous Epithelium; Stains; System; Technology; Testing; Tissue Sample; Tissue imaging; Tissues; Translations; Vagina; accurate diagnosis; clinical translation; comparative; density; experimental study; exposed human population; high-intensity laser; human imaging; human tissue; imaging approach; imaging modality; imaging system; immune function; improved; in vivo; in vivo imaging; insight; interest; irradiation; keratinocyte; meter; monolayer; multiphoton imaging; novel; novel therapeutics; oral cavity epithelium; patient safety; safety assessment; therapy development; translational barrier; treatment response; wound healing

Multiphoton imaging is emerging as a modality with transformative potential for human diagnostic applications, because it can provide morphological and functional tissue information with micron scale resolution, while obviating the need for a biopsy and exogenous contrast agents. However, these imaging systems rely on novel lasers that deliver light to tissue in the form of highly intense, ultrashort pulses, whose interactions with tissues other than the eye and skin are not well-characterized. The lack of established databases that define maximal permissible exposure (MPE) thresholds and a set of methods and protocols that should be used to demonstrate patient safety for a specific set of irradiation conditions presents a critical barrier to the clinical translation of these imaging methods. Our goal is to establish MPE thresholds for NIR, fs pulsed illumination of non-keratinized human squamous oral and cervical epithelia. We will rely initially on engineered human oral and vaginal- ectocervical epithelial tissues that are highly reproducible and commercially available, yet mimic important morphological and functional human tissue characteristics. Using these tissues, we will examine the impact of illumination wavelength, pulse duration, repetition rate, average power, photon density, and total light dose on tissue morphology assessed via histology and proliferation, DNA damage, and apoptosis examined via immunofluorescence. We will also quantify optical metabolic activity using label-free images acquired during tissue illumination with the parameters of interest. We will identify a subset of illumination parameters that yield no, minimal, or moderate damage and we will test these conditions on human cervical tissues (freshly excised and frozen/thawed), human keratinocyte monolayers, and hamster oral epithelia (in vivo, freshly excised and frozen/thawed). Thus, we expect to identify a protocol for the types of specimens that are likely to yield damage assessments that are most relevant to in vivo human squamous epithelial tissues and the combination of a range of light delivery parameters that are not expected to result in any functional damage. We also anticipate that label-free multi-photon imaging-based characterization of tissue morphology and metabolic function will serve as an independent highly sensitive tissue damage indicator. Our findings will be directly relevant to the safe implementation of multi-photon imaging of the human cervix in vivo; however, the approach and MPE conditions we establish will be straightforward to extend to other tissue types and enable translation of this powerful modality to in vivo human imaging.

多光子成像正在成为一种对人类诊断应用具有变革潜力的模式， 因为它可以提供微米级分辨率的形态和功能组织信息，同时 无需活检和外源性造影剂。然而，这些成像系统依赖于新颖的 激光以高强度、超短脉冲的形式将光传送到组织，其与组织的相互作用 除了眼睛和皮肤外，其他部分都没有很好的特征。缺乏定义最大的既定数据库 允许暴露（MPE）阈值以及一组用于证明的方法和协议 特定照射条件下的患者安全对这些技术的临床转化构成了关键障碍 成像方法。我们的目标是建立非角化的 NIR、fs 脉冲照明的 MPE 阈值 人类口腔和宫颈鳞状上皮。我们最初将依靠工程化的人类口腔和阴道- 宫颈外上皮组织具有高度可重复性和市售性，但模拟重要 人体组织的形态和功能特征。使用这些组织，我们将检查 照明波长、脉冲持续时间、重复率、平均功率、光子密度和总光剂量 通过组织学评估组织形态，通过检查增殖、DNA 损伤和细胞凋亡 免疫荧光。我们还将使用在过程中获得的无标记图像来量化光学代谢活动 具有感兴趣参数的组织照明。我们将确定照明参数的子集，从而产生 无、轻微或中度损伤，我们将在人类宫颈组织（新鲜切除的宫颈组织）上测试这些条件 和冷冻/解冻）、人角质形成细胞单层和仓鼠口腔上皮细胞（体内，新鲜切除和 冷冻/解冻）。因此，我们期望为可能产生损坏的样本类型确定一个协议 与体内人类鳞状上皮组织最相关的评估以及一系列的组合 预计不会导致任何功能损坏的光传输参数。我们还预计 基于无标记多光子成像的组织形态和代谢功能表征将发挥作用 作为独立的高灵敏组织损伤指标。我们的研究结果将直接关系到安全 实现人体宫颈活体多光子成像；然而，该方法和 MPE 条件 我们建立的方法将可以直接扩展到其他组织类型并实现这种强大模式的转化 人体体内成像。