Shi Rui, Feng Wei, Zhang Chao, Zhang Zhihong, Zhu Dan
Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics (WNLO), Huazhong University of Science and Technology (HUST), 1037 Luoyu Road, Wuhan, 430074, Hubei, P. R. China.
Key Laboratory of Biomedical Photonics, HUST, Ministry of Education, 1037 Luoyu Road, Wuhan, 430074, Hubei, P. R. China.
J Biophotonics. 2017 Dec;10(12):1647-1656. doi: 10.1002/jbio.201700052. Epub 2017 May 18.
The mouse footpad for its feature of hairlessness provides an available window for imaging vascular and cellular structure and function in vivo. Unfortunately, the strong scattering of its skin limits the penetration of light and reduces the imaging contrast and depth. Herein, an innovative footpad skin optical clearing agent (FSOCA) was developed to make the footpad skin transparent quickly by topical application. The results demonstrate that FSOCA treatment not only allowed the cutaneous blood vessels and blood flow distribution to be monitored by laser speckle contrast imaging technique with higher contrast, but also permitted the fluorescent cells to be imaged by laser scanning confocal microscopy with higher fluorescence signal intensity and larger imaging depth. In addition, the physiological saline-treatment could make the footpad skin recover to the initial turbid status, and reclearing would not induce any adverse effects on the distributions and morphologies of blood vessels and cells, which demonstrated a safe and switchable window for biomedical imaging. This switchable footpad skin optical clearing window will be significant for studying blood flow dynamics and cellular immune function in vivo in some vascular and immunological diseases. Picture: Repeated cell imaging in vivo before (a) and after (b) FSOCA treatment. (c) Merged images of 4 h (cyan border) or 72 h (magenta border) over 0 h. (d) Zoom of ROI in 4 h (yellow rectangle) or 72 h (red rectangle).
小鼠足垫无毛的特性为体内血管和细胞结构及功能成像提供了一个可用窗口。不幸的是，其皮肤的强散射限制了光的穿透，降低了成像对比度和深度。在此，开发了一种创新的足垫皮肤光学透明剂（FSOCA），通过局部应用使足垫皮肤迅速变得透明。结果表明，FSOCA处理不仅能通过激光散斑对比成像技术以更高的对比度监测皮肤血管和血流分布，还能通过激光扫描共聚焦显微镜以更高的荧光信号强度和更大的成像深度对荧光细胞进行成像。此外，生理盐水处理可使足垫皮肤恢复到初始浑浊状态，再次透明处理不会对血管和细胞的分布及形态产生任何不利影响，这证明了其为生物医学成像提供了一个安全且可切换的窗口。这种可切换的足垫皮肤光学透明窗口对于研究某些血管和免疫疾病体内的血流动力学和细胞免疫功能具有重要意义。图：FSOCA处理前（a）和处理后（b）的体内重复细胞成像。（c）4小时（青色边框）或72小时（品红色边框）相对于0小时的合并图像。（d）4小时（黄色矩形）或72小时（红色矩形）感兴趣区域的放大图。
