Cell imaging core amplifies research options with EM
In the past, investigators at Vanderbilt wanting the intricate cellular picture that electron microscopy (EM) affords typically couldn’t make their research plans a reality. Either the instruments around campus weren’t accessible, or the researchers lacked the expertise to use them effectively. Now, another option is available.
W. Gray (Jay) Jerome, Ph.D., associate professor of Pathology and Cancer Biology, has been named director of Research Electron Microscopy, a recent expansion of the Cell Imaging Shared Resource.
The new EM facility broadens the microscopy resources of the fee-for-service Cell Imaging core by providing researchers direct access to a transmission electron microscope (TEM) with a sophisticated digital imaging camera. The staff – including Jerome – is available for training in the use of the microscope and imaging equipment, as well as consultation in experimental design and data interpretation.
“All investigators need to do, then, is come and sit at the scope and make their scientific decisions,” Jerome said. “That’s the one thing researchers must do for themselves.”
Jerome, himself new to Vanderbilt, directed a core microscopy facility at Wake Forest University School of Medicine, with responsibility for a wide array of technologies including standard brightfield microscopy, confocal microscopy, digital imaging, and multiple types of electron microscopy.
“We are very pleased to have Jay Jerome join our faculty and commit his efforts toward adding electron microscopy services to the Cell Imaging Shared Resource,” said Dr. Mark A. Magnuson, assistant vice chancellor for Research.
Electron microscopes use a focused beam of electrons instead of light to “image” a specimen, giving a high-resolution view – up to a 10,000x magnification – of the topography and morphology of cells. The resulting snapshot, or electron micrograph, reveals texture, shape, and size of cellular structures, and some idea of the relationships between them. This fine-scale examination helps to answer questions such as where in a cell a biological substance is located or produced or actively functioning.
For investigators who want to “put numbers on structures,” Jerome said, the staff offers expertise in quantitative digital imaging. This service benefits researchers wanting to match structural detail with information that is primarily numerical, such as physiological or biochemical data.
“You can make a more direct comparison between cells, or cellular structures, if you have similar quantitative data from your images,” Jerome explained. “Rather than just seeing a picture of something, you can learn how much of it there is or how large it is or what percentage of the total volume that element represents.”
The principal microscope for the facility was recently made state-of-the-art with the addition of a cooled CCD camera specific for electron microscopy. Image processing software is available, Jerome said, though investigators may choose to tailor the digital images at their own desks.
The EM service also supports access to a spectrum of other electron microscopes. The pathology department has two instruments – TEM without digital capability – used in the past primarily for clinical diagnostic work. The engineering department houses two other types of scopes: a scanning electron microscope, used for 3-D surface visualization at high resolution, and an intermediate voltage electron microscope, for analysis of much thicker sections and whole cells.
The new facility offers specialized sample processing that requires equipment and chemicals – and expertise – generally unavailable in most labs. Localized deposition of heavy metal onto a tissue specimen is at the heart of most of the staining techniques, ultimately producing a gray-scale contrast map of a cell’s interior.
Jerome buys the facility’s services for his own research investigating how the movement of cholesterol in cells is involved in atherosclerosis. The money and time saved by not having to equip and staff his lab for this technology can be directed toward planning experiments and interpreting results.
“Fees are set up to recoup only the costs involved, so it’s very cost-effective,” Jerome said. “I can rent the facility’s EM technician for a few minutes a couple of days, then rent the microscope and camera for a window of time, and I’m back in the lab analyzing the data.”
As director, Jerome sees it as his primary responsibility to maximize what investigators reap from electron microscopy, to expand their experiments and make the technology work in their best interests.
“The Office of Research at Vanderbilt in particular recognizes that core facilities should exist not only to provide a piece of equipment, but also to provide expertise in how to effectively utilize it,” Jerome said. “It’s quite clear that their philosophy and mine are in parallel.”