Near-infrared photoimmunotherapy (NIR-PIT) is a new cancer therapy that uses NIR light and conjugates of a tumor-targeting monoclonal antibody and phthalocyanine dye. In clinical practice, frontal and cylindrical diffusers are the only options for NIR illumination. However, illumination in a narrow space is technically difficult with such diffusers. Therefore, we evaluated a lateral illumination system using a lateral emitting laser (LEL) fiber. The LEL fiber illuminated a certain area in a lateral direction. NIR-PIT with an LEL fiber reduced luciferase activity in a light-dose-dependent manner in A431-GFP-luc cells in vitro and significantly suppressed tumor proliferation in a xenograft mouse model. To evaluate the usefulness of the LEL fiber in the illumination of a narrow space, a tumor was illuminated from the inside of a cylinder, mimicking a narrow space, and the fluorescence intensity in the tumor was monitored. In the frontal diffuser, NIR light was unevenly delivered and little light reached a distal tumor area from the illuminated side. By contrast, the LEL fiber allowed a uniform illumination of the entire tumor, and a loss of fluorescence was observed even in distal areas. These findings suggested that the LEL fiber can be used for NIR-PIT and is suitable for NIR light illumination in a narrow space.
近红外光免疫疗法（NIR-PIT）是一种新型癌症治疗方法，它结合了近红外光与靶向肿瘤的单克隆抗体-酞菁染料偶联物。在临床实践中，目前仅能使用前向和圆柱形漫射器进行近红外光照射。然而，在狭窄空间内使用此类漫射器进行照射存在技术困难。为此，我们评估了一种采用侧向发射激光（LEL）光纤的侧向照射系统。该LEL光纤可从侧向对特定区域进行照射。在体外实验中，使用LEL光纤的NIR-PIT对A431-GFP-luc细胞的荧光素酶活性产生了光剂量依赖性抑制；在异种移植小鼠模型中，该方法显著抑制了肿瘤增殖。为评估LEL光纤在狭窄空间照射中的适用性，我们模拟狭窄圆柱空间从内部照射肿瘤，并监测肿瘤内荧光强度变化。结果显示：使用前向漫射器时，近红外光分布不均，照射侧远端肿瘤区域几乎无光到达；相比之下，LEL光纤能实现整个肿瘤的均匀照射，即使在远端区域也能观察到荧光减弱现象。这些发现表明，LEL光纤可用于NIR-PIT治疗，尤其适用于狭窄空间的近红外光照射。
Evaluation of a Novel Lateral Emitting Laser Fiber for Near-Infrared Photoimmunotherapy
肿瘤(癌症)患者之家