最先端研究セミナー
講演者： 田村 勝 （理化学研究所バイオリソースセンター マウス表現型解析開発チーム 開発研究員）
演題： Morphometrics of the mouse embryo using the X-Ray Computed Tomography (CT)
日時： 3月14日（水）12：00-13：00
会場： 発生医学研究所1階 カンファレンス室
Abstract:
Classic histological technique using the paraffin sections followed by hematoxylin and eosin staining is a gold standard to detect morphological anomalies of mutants or to compare morphological features of model animals. Though this method is well established and widely performed everywhere, there are following weak points. Preparation of the excellent sections needs dexterous manipulation, and is time-consuming. Reconstruction of the 3D images from the 2D section information is arduous task. In addition to these, genome editing technologies such as CRISPR/Cas9 system make it possible to the gene knockout of various animals, which has no embryonic stem (ES) cells, with unprecedented simplicity and speed. It means that bottleneck of the functional gene analysis will make up the transition from generating the knockout animal to the phenotyping. Therefore, we need easy and high-throughput phenotyping methods.
In medical fields, multi-detector row computed tomography (MDCT) is now commonly used for diagnosis, and becoming a powerful tool for detection and classification of human symptomatic state. X-ray micro-computed tomography (micro-CT) for model animals is identical in its basic principles to MDCT. Micro-CT easily generates 2D slice images at any position and angle, and thereby reconstructs 3D image. It provides excellent images of bone and adipose tissues, because these samples have high contrast Hounsfield unit. Adversely, it has not provided good images of other non-mineralized soft tissues. In this seminar, we would like to introduce an improved method to obtain high resolution of 2D and 3D images of soft tissues in mouse embryos using the micro-CT with inorganic iodine or phosphotungstic acid as a contrast reagent. We also argue about the possibility of this method for future high-throughput morphometrics from various aspects, e.g., degree of resolution, simplicity and costs.
References:
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担当分野： 疾患モデル 荒木（内線：6597）
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