Periodic Reporting for period 1 - Lightsheetelegans (In-toto imaging of C. elegans larval development using adaptive optics light-sheet microscopy)
Reporting period: 2017-03-01 to 2019-02-28
Light-sheet microscopy became one of the most prominent tools for imaging live of developing organisms in systems biology and neuroscience. Activity of neurons in the entire brains of small animals can now be recorded with light-sheet microscopes using genetically encoded calcium indicators.
Conventional light-sheet microscopes usually require that the sample is mounted in a medium with similar refractive index to water (e.g. gel) to allow sufficient working distance and multi-view acquisitions for high resolution imaging. This poses a problem when using light-sheet in combination with microfluidic devices: the presence of the supporting glass plate at a steep angle creates strong optical aberrations and spatial constrains. However, the use of microfluidic devices is desired because they allow precise control of experimental conditions, and thus can widely expand the range of possible experiments with live organisms. Microfluidic devices together with light-sheet microscopy would allow long-term imaging of developing organisms, tissues and organoids grown on chip, and significantly advance our understanding of biological systems.
The overall objective of this project is to build a novel type of microscope that will enable light-sheet imaging of live samples in microfluidic devices.
Conventional light-sheet microscopes usually require that the sample is mounted in a medium with similar refractive index to water (e.g. gel) to allow sufficient working distance and multi-view acquisitions for high resolution imaging. This poses a problem when using light-sheet in combination with microfluidic devices: the presence of the supporting glass plate at a steep angle creates strong optical aberrations and spatial constrains. However, the use of microfluidic devices is desired because they allow precise control of experimental conditions, and thus can widely expand the range of possible experiments with live organisms. Microfluidic devices together with light-sheet microscopy would allow long-term imaging of developing organisms, tissues and organoids grown on chip, and significantly advance our understanding of biological systems.
The overall objective of this project is to build a novel type of microscope that will enable light-sheet imaging of live samples in microfluidic devices.
We designed and constructed a novel multi-view light-sheet microscope that addresses the problem by using an adaptive optics element (deformable mirror). The deformable mirror corrects optical aberrations imposed by the tilted glass plate (microfluidic chip). We also manufactured microfluidic chips required for the operation of the microscope. We demonstrated our technique by imaging neuronal activity in the C.elegans nematode nervous system mounted inside a microfluidic channel.
During the project we invented a novel optical arrangement (patent application in preparation), which can be applicable to design new types of microscopes and minimize the cost of existing ones. We are currently optimizing the speed and resolution of our microscope. We are further collecting experimental data on C.elegans nervous system activity during the exit from dauer (developmental arrest) stage. This will allow deeper understanding of the fundamental mechanisms that govern nervous system activity and remodelling during organism development.