The annual American Society for Cell Biology meeting was held in San Diego, California from December 12 to December 16. The conference presentations and exhibit were abuzz with research results made possible by new technology developments, most notably super-resolution microscopy and single-cell analysis. Super-resolution microscopy techniques improve the spatial resolution of optical microscopy.

Sunday kicked off with a symposium that included two 2014 Nobel Prize winners for Chemistry for their development of super-resolution fluorescence microscopy, Eric Betzig, PhD, of Janelia Research Campus, Howard Hughes Medical Institute, and William E. Moerner, PhD, of Stanford University. Entitled “Pushing the Limits: Visualization of Hidden Biological Processes,” the symposium highlighted the development and future potential of specific super-resolution microscopy techniques. In his talk, “In Vivo Imaging of Cellular Dynamics from the Nanoscale to the Macroscale,” Dr. Betzig highlighted his use of live-cell total internal reflection fluorescence (TIRF) structured illumination microscopy (SIM) to image depths of 50–100 nm. TIRF selectively excites fluorophores near the sample surface using an evanescent wave. SIM uses directed patterns of light to collect multiple images that are then reconstructed. Using nonlinear SIM with patterned activation, in which only a selected set of fluorophores is activated and deactivated using different patterns of light, resulted in resolution down to 63 nm.

He also discussed the use of lattice light-sheet microscopy for fast, noninvasive 4-D live-cell imaging, noting its suitability for single-molecule imaging and tracking. Lattice light-sheet microscopy uses a single sheet of light to simultaneously image multiple planes. A goal for lattice light-sheet microscopy is to image large multicellular volumes, specifically to be able to look at cells inside an organism for endogenous expression at low toxicity. Future areas of technology development include combining lattice light-sheet microscopy with adaptive optics, which correct for aberrations introduced by the refractive index of the sample. Dr. Betzig ended his talk commenting that he believes SIMS is “going to be the most important super-resolution technique within a decade.” He also promoted the Janelia Research Campus’s Advanced Imaging Center, which houses several super-resolution techniques and is available for use free of charge.

In her talk entitled, “Illuminating Biology at the Nanoscale with Single-Molecule and Super-Resolution Fluorescence,” Xiaowei Zhuang, PhD, of Harvard University discussed another super-resolution technique, stochastic optical reconstruction microscopy (STORM) and her use of 3-D STORM. Developed by Dr. Zhuang’s lab, STORM utilizes light to switch fluorescent probes on and off, with the location captured and the series of images reconstructed. Improving STORM using an Airy beam scheme, she achieved isotropic 3-D resolution of 10 nm in x, y and z in all directions. Resolution was also improved using ultra bright photo-activated dyes. In addition, she highlighted the use of STORM for live-cell imaging to study cellular dynamics at 20 nm spatial resolution and one-second time resolution. Applications include the discovery of cellular structure, imaging of live neurons and development of a 3-D structure of the genome for use in studying gene expression regulation. Using STORM combined with Oligopaint FISH probes, which are fluorescently labeled, single-strand oligonuceliotides, a 3-D image of chromatin was obtained for study of chromatin organization and regulation, and their connection to epigenetic states. She also described the use of STORM for transcriptome imaging using single-molecule FISH.

In his talk entitled, “The Story of Single Molecules, from Early Spectroscopy in Solids, to Super-resolution Microscopy to 3D Dynamics of Biomolecules in Cells,” Dr. Moerner discussed the validation of 3-D super-resolution imaging and tracking.

Launched at the show was NanoLive’s 3D Cell Explorer, a tomographic microscope for noninvasive, label-free and marker-free live-cell imaging in real time. Rotational scanning takes 96 z-stack grayscale images to construct a 3-D image that can be analyzed using “digital staining,” in which the pixels of the same refractive index are colorized. According to NanoLive, the system provides an alternative to fluorescence microscopy, for which the sample must be chemically or genetically modified. Resolution is 200 nm in x and y and 500 nm in z, and provides a detection range of 90 x 90 x 30 µm. Applications include studies of live and fixed single cells, imaging of cell-cell interactions, imaging of cell culture, and use with histological and cytological samples. The system is priced at €19,900 ($21,868 = €0.91 = $1). Deliveries will begin early next year.

At ASCB, Becton, Dickson introduced the FACSCelesta, a mid-level flow cytometer with a 24 in. x 24 in. x 24 in. footprint. The system accommodates up to three lasers in as many as four configurations and a maximum of 12 colors. Designed for use with Becton’s BD Horizon Brilliant reagents, the system can measure 14 single-cell parameters. It is priced at $100,000–$150,000. The company also displayed its BDFacSeq system, a modification of a BD cell sorter to allow single-cell sorting. Each cell can be dispensed into one well of a 96-well PCR plate for subsequent analysis, or into tubes or plates. Minimum sample volume is 0.2 mL, and up to four cellular parameters can be measured before isolation. The system is designed for genomics applications, such as single-cell sequencing.

Zephyrus Biosciences debuted its first product at the show. The Z1 Instrument is a single-cell western blotting system that can image more than one thousand individual single cells. A maximum of four proteins can be probed per cell. Time from sample to image is 4–5 hours. Using the microfluidic zWest chip, cells are lysed, proteins separated by SDS-PAGE, bound to the gel and probed with primary and fluorescently labeled secondary antibodies. The image is analyzed with a microarray scanner and software. ZWest chips can be reprobed or archived. Applications include validation of RNA-Seq results and the study of the transcription in a subpopulation of T cells. The system is priced at $50,000.

ASCB 2016 will be held December 3–7 in San Francisco, California.