优化基于大小和形态的外体准备:从电子显微镜的见解
Noriyuki Ishii1,2,3, Keiichi Noguchi4, Mitsushi J Ikemoto5,6
1Cellular and Molecular Biotechnology Research Institute, Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central-6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
概括
优化细胞外囊泡 (EV) 隔离,这项研究发现,无盐的缓冲区保留了EV的完整性,并揭示了不同的规模群体. 这提高了用于生物医学应用的外体表征.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 纳米技术纳米技术
背景情况:
- 细胞外囊泡 (EVs),包括外体,是细胞间通信的关键媒介.
- 由于尺寸和形态重叠,难以区分外体与其他EV,如微微囊.
- 多胞体 (MVBs) 是外体生物发生和成熟的关键地点.
研究的目的:
- 为了优化外体隔离和表征方法.
- 调查缓冲组合对电动汽车完整性和尺寸分布的影响.
- 在MVP中识别与外体生物发生相关的独特的EV群体.
主要方法:
- 传输电子显微镜 (TEM) 用于高分辨率的尺寸和形态分析.
- 动态光散射 (DLS) 用于纳米粒子尺寸分布的评估.
- 免疫电子显微镜验证外体生物标记物的存在 (CD63).
- 使用无盐的Bis-Tris与酸盐缓冲盐水 (PBS) 和高盐的Bis-Tris进行比较缓冲分析.
主要成果:
- 与PBS相比,没有盐的Bis-Tris缓冲剂更好地保持细胞外囊泡 (EV) 的完整性.
- 在没有盐的Bis-Tris中,完整的外基因组分数显示多分散性,包括<50 nm人口,类似于内囊泡 (ILV).
- 这种<50 nm人口在PBS或高盐Bis-Tris中丢失,EV聚合成更大,单分散群 (>100 nm).
- 通过免疫电子显微镜,CD63是一种外体标记物,在约50纳米的EV中得到证实.
结论:
- 没有盐的缓冲区对于保持外体的原生尺寸分布和完整性至关重要.
- 该研究确定了一种独特的小EV (<50 nm) 群体,这些EV来自MVB,对于准确的外体特征表征至关重要.
- 这些优化的隔离和表征方法对于推进基于外体的诊断和药物输送系统至关重要.
相关概念视频
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Optical microscopy uses optic principles to provide detailed images of samples. Antonie van Leeuwenhoek designed the first compound optical microscope in the 17th century to visualize blood cells, bacteria, and yeast cells. In 1830, Joseph Jackson Lister created an essentially modern light microscope. The 20th century saw the development of microscopes with enhanced magnification and resolution.
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
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01:15Transmission Electron Microscopy
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01:29Two-Dimensional Microscopy in Microbiology
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