Limits...
Episcopic 3D Imaging Methods: Tools for Researching Gene Function.

Weninger WJ, Geyer SH - Curr. Genomics (2008)

Bottom Line: The most advanced are capable of generating high-resolution volume data (voxel sizes from 0.5x0.5x1 microm upwards) of small to large embryos of model organisms and tissue samples.Beside anatomy and tissue architecture, gene expression and gene product patterns can be three dimensionally analyzed in their precise anatomical and histological context with the aid of whole mount in situ hybridization or whole mount immunohistochemical staining techniques.Such applications, however, are not yet routine and currently only preliminary results are available.

View Article: PubMed Central - PubMed

Affiliation: IMG, Centre for Anatomy and Cell Biology, Medical University of Vienna, Waehringer Str. 13, A-1090 Vienna, Austria.

ABSTRACT
This work aims at describing episcopic 3D imaging methods and at discussing how these methods can contribute to researching the genetic mechanisms driving embryogenesis and tissue remodelling, and the genesis of pathologies. Several episcopic 3D imaging methods exist. The most advanced are capable of generating high-resolution volume data (voxel sizes from 0.5x0.5x1 microm upwards) of small to large embryos of model organisms and tissue samples. Beside anatomy and tissue architecture, gene expression and gene product patterns can be three dimensionally analyzed in their precise anatomical and histological context with the aid of whole mount in situ hybridization or whole mount immunohistochemical staining techniques. Episcopic 3D imaging techniques were and are employed for analyzing the precise morphological phenotype of experimentally malformed, randomly produced, or genetically engineered embryos of biomedical model organisms. It has been shown that episcopic 3D imaging also fits for describing the spatial distribution of genes and gene products during embryogenesis, and that it can be used for analyzing tissue samples of adult model animals and humans. The latter offers the possibility to use episcopic 3D imaging techniques for researching the causality and treatment of pathologies or for staging cancer. Such applications, however, are not yet routine and currently only preliminary results are available. We conclude that, although episcopic 3D imaging is in its very beginnings, it represents an upcoming methodology, which in short terms will become an indispensable tool for researching the genetic regulation of embryo development as well as the genesis of malformations and diseases.

No MeSH data available.


Related in: MedlinePlus

Flow chart of the episcopic 3D data generation protocol. Note that this flow chart provides only the main steps. Depending on the method, additional steps might be necessary for analysing gene expression patterns.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2682936&req=5

Figure 2: Flow chart of the episcopic 3D data generation protocol. Note that this flow chart provides only the main steps. Depending on the method, additional steps might be necessary for analysing gene expression patterns.

Mentions: All episcopic 3D imaging techniques utilize sacrificed embryos and tissue samples. The specimens are fixed and sometimes pre-processed and whole mount stained for enhancing contrasts. Then they are embedded in histological embedding media and mounted on a microtome. Digital images of the tissues on the surfaces of the blocks of embedding medium containing the specimens are captured with a camera sitting on a magnifying optic. The optical pathway of the optic is aligned precisely perpendicular to the block surface (Fig. 1). Depending on the technique the tissues on the block surface are either identified by their intrinsic contrast or by administering dyes to the block surface. After capturing an image of the block face, a small slice of the block is removed using either the microtome blade or micro-mills. Routinely this slice is thrown away, although some methods permit preservation of histological sections. Now, a digital image of the freshly cut - if necessary also freshly stained - block surface is captured and the next slice of embedding medium is removed. This procedure is repeated until the region of interest is sectioned and a stack of aligned digital images, showing subsequent block faces with tissue of the specimens is produced (Fig. 2). In some methods, data generation is fully automated. This generates homogeneous data sets, and saves time and man power.


Episcopic 3D Imaging Methods: Tools for Researching Gene Function.

Weninger WJ, Geyer SH - Curr. Genomics (2008)

Flow chart of the episcopic 3D data generation protocol. Note that this flow chart provides only the main steps. Depending on the method, additional steps might be necessary for analysing gene expression patterns.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2682936&req=5

Figure 2: Flow chart of the episcopic 3D data generation protocol. Note that this flow chart provides only the main steps. Depending on the method, additional steps might be necessary for analysing gene expression patterns.
Mentions: All episcopic 3D imaging techniques utilize sacrificed embryos and tissue samples. The specimens are fixed and sometimes pre-processed and whole mount stained for enhancing contrasts. Then they are embedded in histological embedding media and mounted on a microtome. Digital images of the tissues on the surfaces of the blocks of embedding medium containing the specimens are captured with a camera sitting on a magnifying optic. The optical pathway of the optic is aligned precisely perpendicular to the block surface (Fig. 1). Depending on the technique the tissues on the block surface are either identified by their intrinsic contrast or by administering dyes to the block surface. After capturing an image of the block face, a small slice of the block is removed using either the microtome blade or micro-mills. Routinely this slice is thrown away, although some methods permit preservation of histological sections. Now, a digital image of the freshly cut - if necessary also freshly stained - block surface is captured and the next slice of embedding medium is removed. This procedure is repeated until the region of interest is sectioned and a stack of aligned digital images, showing subsequent block faces with tissue of the specimens is produced (Fig. 2). In some methods, data generation is fully automated. This generates homogeneous data sets, and saves time and man power.

Bottom Line: The most advanced are capable of generating high-resolution volume data (voxel sizes from 0.5x0.5x1 microm upwards) of small to large embryos of model organisms and tissue samples.Beside anatomy and tissue architecture, gene expression and gene product patterns can be three dimensionally analyzed in their precise anatomical and histological context with the aid of whole mount in situ hybridization or whole mount immunohistochemical staining techniques.Such applications, however, are not yet routine and currently only preliminary results are available.

View Article: PubMed Central - PubMed

Affiliation: IMG, Centre for Anatomy and Cell Biology, Medical University of Vienna, Waehringer Str. 13, A-1090 Vienna, Austria.

ABSTRACT
This work aims at describing episcopic 3D imaging methods and at discussing how these methods can contribute to researching the genetic mechanisms driving embryogenesis and tissue remodelling, and the genesis of pathologies. Several episcopic 3D imaging methods exist. The most advanced are capable of generating high-resolution volume data (voxel sizes from 0.5x0.5x1 microm upwards) of small to large embryos of model organisms and tissue samples. Beside anatomy and tissue architecture, gene expression and gene product patterns can be three dimensionally analyzed in their precise anatomical and histological context with the aid of whole mount in situ hybridization or whole mount immunohistochemical staining techniques. Episcopic 3D imaging techniques were and are employed for analyzing the precise morphological phenotype of experimentally malformed, randomly produced, or genetically engineered embryos of biomedical model organisms. It has been shown that episcopic 3D imaging also fits for describing the spatial distribution of genes and gene products during embryogenesis, and that it can be used for analyzing tissue samples of adult model animals and humans. The latter offers the possibility to use episcopic 3D imaging techniques for researching the causality and treatment of pathologies or for staging cancer. Such applications, however, are not yet routine and currently only preliminary results are available. We conclude that, although episcopic 3D imaging is in its very beginnings, it represents an upcoming methodology, which in short terms will become an indispensable tool for researching the genetic regulation of embryo development as well as the genesis of malformations and diseases.

No MeSH data available.


Related in: MedlinePlus