Here are examples of some of our more complicated/ unusual Leica experimental setups:

1) Taste response in adult Drosophila (Gregg Roman’s Lab)

This setup using the large translational stage allows the researchers to present different tastes to an immobilized fly via a strip of blotting paper.

The fly carries a GCaMP transgene, expressed in the brain, which will increase its fluorescence when there is a rise in levels of intercellular Ca++, an indicator of neural activity. The top of the fly’s head cuticle has been removed to allow imaging with a ceramic dipping objective, which measures the changes in GCaMP fluorescence intensity in response to the taste stimulus.

2) Materials Science setup: scanning shoe bottoms to measure wear patterns

For this setup both the slide holder and the condenser were removed. Since the material of the shoes was not fluorescent, we used the reflection mode to collect images of the surfaces.

A 3-D rendering of one of the surface scans:

A rotation of the above image:

3) Electrophysiology with live brain slices (Jokubus Ziburkus Lab)

Here the slide holder has been removed from the translational stage to accommodate a perfusion chamber for the rat brain tissue slice:

Here’s a wider shot of the whole setup, which includes a Digidata 1440 digitizer (Axon instruments, analog to digital 10kHz sampling rate), which translates the amplified electrical from the tissue, a perfusion system to reservoir drip ACSF (artificial cerebro-spinal fluid, gravity fed input), a heating element to maintain a temperature of 32°C, a feed from an oxygen tank to bubble O2 into reservoir, and micromanipulators to position the specimen.

The brain slice is treated with the dye Natrium green (tracks Na+ ion movement), and the perfusion system is used to deliver a drug to the tissue to induce the equivalent of seizures.