Microscopy

Our experimental approach makes extensive use of the latest technologies that facilitate volumetric imaging of biological samples at the cellular and tissue scales. For example, the Photonic Bioimaging Center of the Biology Division provides us with a range of advanced Light sheet fluorescence microscopy (LSFM) and confocal fluorescence microscopy systems.  

LSFM uses a thin sheet of light to excite fluorescent labels within a sample, such as signal from nuclear staining or antibodies. By moving the sample (or the sheet of light) up or down whilst acquiring a series of images, we can generate 3D data that includes multiple different signals. This allows us to precisely capture complex tissue geometries and molecular signalling. One cutting-edge LSFM system — the Ultramicroscope Blaze — is of particular interest to our laboratory because it is adapted to the imaging of samples that can vary dramatically in size and composition, including embryonic crocodile jaws and embryonic elephant trunks.

Confocal microscopy uses a highly-focused beam to illuminate the sample that is being imaged. This beam scans across the sample sequentially to illuminate an entire 2D plane. The process is repeated for successive planes to produce a 3D image. By blocking out-of-focus light, confocal microscopy precisely excites fluorescent signals found within our samples, and allows us to capture data at higher resolutions. However, the speed of acquisition is slower than for light-sheet imaging.

Note that we have developed a simple and robust method of whole-mount staining with the ‘Fast Green’ dye that provides unmatched visualisation of 3D collagen network architecture, via confocal or light-sheet microscopy.