State Key Laboratory of Ultrasound Engineering in Medicine Co-Founded by Chongqing and the Ministry of Science and Technology, College of Biomedical Engineering, Chongqing Key Laboratory of Biomedical Engineering; Chongqing Medical University, Chongqing Collaborative Innovation Center for Minimally-Invasive and Noninvasive Medicine, Chongqing, China.
Eur Rev Med Pharmacol Sci. 2020 May;24(10):5714-5725. doi: 10.26355/eurrev_202005_21363.
Anaerobic bacteria can enter the solid tumor in the hypoxic region to colonize and proliferate. Aggregation of nanoparticles in the tumor area can enhance molecular imaging and therapy. It is hypothesized that the combination of the two could possibly achieve better imaging and tumor treatment. This study presents a biocompatible bacteria-based system that can deliver cationic phase-change nanoparticles (CPNs) into solid tumor to achieve enhanced imaging and treatment integration.
Cationic phase-change nanoparticles (CPNs) and Bifidobacterium longum (BF) were mixed to determine the best binding rate and were placed in an agar phantom for ultrasonography. BF-CPNs complex adhesion to breast cancer cells was observed by laser confocal microscopy. In vivo, BF-CPNs and control groups were injected into tumors in breast cancer nude mouse models. Nanoparticles distribution was observed by ultrasound and in vivo fluorescence imaging. HIFU ablation was performed after injection. Gross and histological changes were compared and synergy was evaluated.
Bifidobacterium longum (BF) and CPNs were combined by electrostatic adsorption. The BF-CPNs particles could increase the deposition of energy after liquid-gas phase-change during High Intensity Focused Ultrasound (HIFU) irradiation of tumor.
This study shows a valid method in diagnosis and therapy integration for providing stronger imaging, longer retention time, and more effective tumor treatment.
厌氧菌可进入缺氧区域的实体瘤中定植和增殖。纳米颗粒在肿瘤区域的聚集可以增强分子成像和治疗效果。假设两者结合可能会实现更好的成像和肿瘤治疗效果。本研究提出了一种基于细菌的生物相容性系统，该系统可以将阳离子相变纳米颗粒（CPN）递送至实体瘤中，以实现增强的成像和治疗一体化。
将阳离子相变纳米颗粒（CPN）和长双歧杆菌（BF）混合，以确定最佳结合率，并将其置于琼脂体模中进行超声检查。通过激光共聚焦显微镜观察 BF-CPN 复合物对乳腺癌细胞的黏附作用。在体内，将 BF-CPN 复合物和对照组注射到乳腺癌裸鼠模型的肿瘤中。通过超声和体内荧光成像观察纳米颗粒的分布。注射后进行高强度聚焦超声（HIFU）消融。比较大体和组织学变化，并评估协同作用。
长双歧杆菌（BF）和 CPN 通过静电吸附结合。BF-CPN 颗粒在肿瘤的高强度聚焦超声（HIFU）照射下发生液-气相变时，可增加能量沉积。
本研究为诊断和治疗一体化提供了一种有效的方法，可实现更强的成像、更长的保留时间和更有效的肿瘤治疗效果。
