MDI Biological Laboratory

Take a Closer Look: Microscopy at MDIBL

  • March 19, 2022

While scientific images are often stunning from an artistic point of view, for the scientists, the beauty of the image is most often contained in the answers it can give them. Frédéric Bonnet,Ph.D., manager of MDI Biological Laboratory’s Light Microscopy Facility (LMF) strives to make sure that users have up-to-date training to make sure they can obtain information that is beneficial to their research. 

Over the last few years, the MDI Biological Laboratory has heavily invested in the LMF, primarily with the with support of the Maine IDeA Network of Biomedical Research Excellence (INBRE) grant. INBRE, which aims to build research capacity in states that have historically received lower levels of funding,  is a collaborative network of Maine educational and research institutions led by the MDI Biological Laboratory and sponsored by the National Institute of General Medical Sciences (NIGMS) of the National Institutes of Health (NIH).

The LMF is responsible for the seven microscopes on campus at MDIBL. Fundamentally necessary to aid modern scientific research, the imaging needs of faculty can range from whole organism to samples that are only nanometers (nm) in size (a nanometer is one billionth of a meter). With a diverse set of imaging needs amongst MDIBL faculty and collaborators, MDIBL maintains a range of scopes:

Two macroscopes are used to observe large samples or complete model organisms. These macroscopes are capable of zooming in from an overview to small details, easily and without changing the objective, and allow  screening and phenotyping experiments using either brightfield imaging (where the sample is illuminated with white light) or epifluorescence imaging (widely used in cell biology, it involves the marking of the protein of interest glowing in the dark).

Two Zeiss widefield microscopes allow for imaging of smaller samples, such as model embryos, tissue sections or cells through either the brightfield or epifluorescence methods. One of the additional benefits to the high-quality microscopes at MDIBL are their ability to be customized to meet our evolving needs.  Last year, one of the widefield microscopes was updated with the addition of an incubation chamber for better preservation of samples during imaging, and a new system that allows for viewing samples across the color spectrum and provides for new options for how that light is used. The update also added a motorized stage, allowing for multi-position imaging or ‘stitching’ – a process that creates continuous images of longer samples. These upgrades created new opportunities for faculty, students, and course attendees alike, as previously impossible experiments could now be conducted in our labs.

MDIBL has two laser scanning confocal microscopes for high quality imaging, including deep tissue in-vivo imaging. Our newest microscope, an LSM-980, the first of its kind installed in Maine, was funded entirely by the INBRE research program. It takes images up to 120nm in resolution, higher than ever before.  Image analysis software, IMARIS,  was purchased to aid users in analyzing, segmenting and quantifying parameters on these high-resolution images in 3D.

While the investment in maintaining, upgrading, and purchasing new scopes is significant, it has been made possible with the support of the INBRE grant, and the impact on our research outcomes is immense. We have high quality equipment, resources and expertise in place at MDIBL, now we hope to engage a wider audience of users through the microscopy remote interaction program.

The idea of a remote service was already percolating when Bonnet started his role at MDIBL in 2019, but the COVID pandemic offered an opportunity to roll out the idea. MDIBL ran a pilot of remote microscope services with INBRE investigator and University of Maine Farmington associate professor Tim Breton, Ph.D. Breton noted that that “the microscopy remote interaction program has solved our imaging issues by allowing our smaller campus to both use these resources from a distance and leverage expertise made available by the Light Microscopy Facility.” The collaboration resulted in a paper published in Scientific Reports in 2021. Now, users can send their samples to the LMF, and in consultation with Bonnet, create images that meet their needs. Today, users from University of Maine Orono are working with the LMF through remote services and other collaborators will join us in 2022.

Education is a priority for Bonnet, teaching microscopy techniques and knowledge to the next generation of scientists by writing and teaching modules for students that cater to their needs as microscope users. Students learn a range of skills from the proper design and analysis of a microscopy experiment to honing techniques to capture better images. His passion for the subject is clear: “When students are exposed to a research microscope and its environment, they discover a new and fascinating world. The first time they see into a tissue section, or cell, or when they view structures moving over time – it’s impressive. When they see how an advanced research microscope works and the quality of the images you can obtain – they get hooked!”. A new microscopy course for Maine students, co-created by the LMF and UMaine Orono will take place in June.

MDIBL is proud of the level of expertise the LMF offers – in both equipment and in personnel – and the benefit it offers to our research groups, our INBRE partners and other collaborators. Bonnet describes the approach as win-win; “the ability to share our resources with the wider scientific community betters the field of biological sciences in Maine and beyond.”