Light Sheet Microscopy for Developmental Biology

The Crick is a partnership between the Medical Research Council, Cancer Research UK, the Wellcome Trust and three leading universities: UCL (University College London), Imperial College London and King's College London. The Crick aspires to be one of the world's leading medical research institutes. The Crick achieves operational and research efficiencies and economies-of-scale through centralised facilities and functions, known as Science Operations, that provide all researchers at the Crick, irrespective of affiliation, with access to cutting-edge equipment, animals for research and laboratory enabling functions such as light microscopy.

Light microscopy is a fundamental research tool with powerful instruments available to perform different functions. Different instruments are required because different arrangements of the basic components of a light microscope - a light source, a lens system, a sample and a detector - have strengths and weaknesses for their application depending on their arrangement. Confocal microscopy can be used to study the dynamics of fluorescently labelled cells in culture, however the method is poorly suited for the study of thicker tissue samples. The result is an image of specific cell structures without knowing where the cells sits in an organ, a bit like not being able to see the wood for the trees. In contrast, Light sheet microscopy, the subject of this grant application, uses a light source and lens arrangement that is able to develop an image from near-parallel light i.e. a light sheet. This allows visualisation of cells and sub-cellular structure deep within samples such as tissue and developing zebrafish embroys.

This attribute makes light sheet microscopy particularly powerful for studying how cells grow, move and organise during normal growth e.g. as embryos develop, or abnormal growth e.g. as cancer develops. By understanding how cells grow, move and organise we expect to able to identify where problems arise and investigate how to solve problems, ultimately leading to new medical approaches to support human fertility, treat cancer or other diseases that are caused by abnormal cell functions.

The Crick aspires to be one of the world's leading medical research institutes. It achieves research efficiencies through centralised facilities and functions such as the Advanced Light Microscopy Scientific Technology Platform (STP). A BBSRC funded light sheet microscope would be placed in the Light Microscopy STP and made available to 90+ research groups at the Crick, and their collaborators. This application is being made by several Crick Group Leaders (Briscoe, Wilkinson, Hill, Niakan, Li and Pachnis). Their research is used to illustrate the potential of a light sheet microscope to empower research at the Crick:

- Briscoe: quantitative imaging of specific transgenic reporters (e.g. Olig2 and Irx3) in the embryonic neural tube will provide insight into cellular patterning co-ordination;
- Wilkinson: Light sheet microscopy will enable live imaging of transgenic and mutant cells lines like knock-ins for hoxb1a (r4) and for markers of different progenitor and neuronal cell populations (e.g. Rfng, Metrnl, neurog1) in the study of hindbrain neurogenesis;
- Hill: measurement of Nodal signalling over time in cells specified to become endoderm or mesoderm;
- Niakan: immunofluorescence analysis of human embryos, investigating the expression of pluripotency factors (e.g. OCT4, NANOG) and factors enriched in the developing pluripotent epiblast (e.g. KLF17 and ARGFX) where light sheet microscopy visualisation of gene expression within the tightly formed cluster of pluripotent cells would further inform stem cell strategies towards clinical use;
- Li: understanding how Wnt signalling is regulated in normal intestine and cancer development;
- Pachnis: using zebrafish larvae to investigate the enteric nervous system and link neurons, neuronal activity and motor output to understand the functional consequences of Hirschsprung disease.

The Crick aspires to be one of the world's leading medical research institutes. Its multidisciplinary approach, an emphasis on practical application of research and its links with academia, industry and the public sector will speed up the translation of discoveries made in the laboratory into treatments for disease. We fully expect outcomes from the light sheet microscopy system and its use by researchers across the Crick to have a pathway to impact through both academic impact and economic and societal impacts.

Academic impact:
- Publication via various media including papers and conference presentations;
- Knowledge transfer and education, especially with respect to PhD students and early-career researchers / post-doctoral research associates.

Economic and societal impact:
- The Crick, its founding partners (the Medical Research Council, Cancer Research UK, the Wellcome Trust, UCL (University College London), Imperial College London and King's College London), and legacy research institutes at Mill Hill (MRC), Lincoln's Inn Fields and Clare Hall (CRUK) all have strong track records for converting research and discoveries into economic and societal benefit;
- The Crick organisation includes well-funded and specific groups responsible for Translation, Clinical Research, Public Engagement and Education, thus we are confident that research outcomes from the BBSRC funded light sheet microscope will convert into economic and societal benefits.