The Microscopy and Cell Analysis Core provides three complementary high-end services to Mayo Clinic Cancer Center investigators. These include electron microscopy, flow cytometry and cell sorting, and optical microscopy.

Electron microscopy

The core has one scanning and three transmission electron microscopes (TEMs). The TEMs are all 120 kilovolt instruments that are typically operated at 70 to 80 kilovolts. Each instrument is in use throughout the day (7 a.m. to 10 p.m.) with regular daily in-service and periodic contract maintenance to ensure instrument operation.

One of these instruments, the JEOL JEM-1400 transmission electron microscope (TEM), is equipped with a goniometry stage for cryo-tomography frozen preparations or imaging of thick-sectioned, epoxy-embedded material. Standard transmission and scanning electron microscopy, immune-labeling, negative staining and cyro-tomography methods are supported. In addition, 3-D reconstruction from serial thin sections and correlative light and electron microscopy are available to investigators.

Flow cytometry and cell sorting

The core has five analytical flow cytometers. Flow analysis methods and cell sorting services allow characterization of properties of cells or particles through the use of fluorescent probes, lasers, advanced electronics, high-quality optics and specialized software. Flow cytometry provides high-speed analysis and characterization of single cells or a particle in suspension. This technology enables investigators to quantitatively assess the properties of large numbers of individual cells. Data on apoptosis, transfection efficiency, cell-surface marker expression, calcium flux and others can be measured.

In addition to analysis, cells exhibiting specific characteristics can be physically sorted from a mixed population and collected for culturing further studies using one of the cell sorters.

Optical microscopy

Optical microscopy provides instrumentation that can examine either tissue or single cells microscopically. Through the use of advanced imaging technologies, quantitative information or digital images can be obtained and stored.

Both upright and inverted fluorescence microscopes are available that can be interfaced to a variety of cameras and image-recording devices for image capture. A ratiometric microscopy workstation is provided for single cell kinetic studies.

The confocal laser scanning microscopes can be used to optically section specimens, thus preserving ultrastructure registration better than do conventional physical sectioning techniques. Compartmental localization of markers within a cell is possible, as is 3-D reconstruction of serial images. Multiphoton microscopy allows investigators to image at high resolution, in thick specimen preparations and in deep (1 millimeter) tissue of living animals.

Finally, using the recently acquired super-resolution technique with structured illumination and photo-activated localization microscopy, investigators can achieve high resolution (< 0.1 µ to 40 nm) of appropriately labeled proteins in cells and tissue preparations. Utilizing specialized software, quantization of image properties can be performed by macro programs written by core personnel.

Major instrumentation available

Electron microscopy

  • JEOL JEM-1400 TEM
  • FEI Tecnai G2 Spirit TEM
  • FEI Tecnai T12 TEM
  • Noran System 7 X-ray detector
  • Hitachi S-4700 FE SEM
  • Ultramicrotome Leica EM UC7
  • FEI Vitrobot

Optical microscopy

  • 2x Zeiss LSM 780 confocal microscopes
  • 3x Zeiss LSM 510 confocal microscopes
  • 2x Zeiss Axiovert Apotome microscopes
  • Zeiss LSM 5 Live confocal microscope
  • Zeiss Axioplan 2
  • Zeiss Laser TIRF
  • 2x Olympus multiphoton microscopes

Flow and cell sorting

  • BD FACScan cytometer
  • 2x BD FACSCalibur flow cytometers
  • BD FACSCanto flow cytometer
  • BD LSR II flow cytometer
  • BD FACSVantage cell sorter
  • BD FACSAria cell sorter

In addition, a wide variety of preparative equipment and computer-aided image processing and analysis workstations are available within the core.