The goal of a research team at Sandia National Laboratories is to analyze between 10 and 40 proteins in a single cell with three-dimensional resolution.
The team’s work on immunity and immune cells has potential implications for combating bioterrorism, according to investigators working on the project.
Sandia uses lab-on-a-chip technology to look at cells individually, according to Anup Sigh, the principal investigator for the Laboratory Directed Research and Development project at Sandia Labs. Built-in lasers and photodiodes read the results in the chips, while an internal microprocessor automates analysis of the results.
“We can insert single cells into a chip, keep them alive, manipulate them, challenge them, sort them, lyse them, analyze the proteomic content of that particular cell, and even do imaging of that single cell,” Singh said. “Sophisticated computational models are then used to convert this data into signaling networks.”
Sandia, based in Livermore, Calif., is doing confocal microscopy in addition to flow cytometry and immunoassays, Singh said, adding that all of the work is being done on one platform.
Though Singh said the platform is integrated, he pointed out that “the caveat is we are not doing the imaging or the flow cytometry at the same time.”
Singh said that the same batch of cells is divided into two parts: one for imaging and the other for flow cytometry. He said that the cells get arrayed on a chip and can then be studied using a confocal microscope during stimulation with pathogens.
The second group of cells is infected in exactly the same way, said Singh. They are either fixed, stained, and interrogated one cell at a time, or are lysed together, and the proteins from those cells are pooled. Then an on-chip immunoassay is done to measure cytokines or phosphorylated proteins.
Singh pointed out that this platform is applicable to many areas that involve analysis of intracellular activity. For example, it can be applied to other cell-signaling pathways, such as those involved in cancer or infectious diseases.
Sandia is partnering with the University of California, San Francisco, and the University of Texas Medical Branch at Galveston on the current project. In an e-mail to CBA News, Bill Seaman, a professor of medicine and microbiology and immunology at UCSF, mentioned several reasons why the team thought the collaboration with Sandia was a good fit.
“The project involved the response by macrophages to pathogens, an important area, and the model proposed was the mouse macrophage cell line, RAW264.7,” he wrote. “We have considerable experience with this cell line, most importantly, because it is the cell line used by the Alliance for Cellular Signaling, a consortium of universities dedicated to better understanding how cells interpret signals in a context dependent manner. The AfCS uses this cell line to study transmembrane signaling.”
Seaman directs a laboratory that is part of the AfCS, and said that much of his lab’s past and present work complements Sandia’s research. However, Seaman said, Sandia brings new expertise and tools to bear on responses by this particular murine cell line.
“We can insert single cells into a chip, keep them alive, manipulate them, challenge them, sort them, lyse them, analyze the proteomic content of that particular cell, and even do imaging of that single cell.”
He pointed out that in addition to Sandia’s ability to analyze single cells, the lab also has expertise in pathogens that are potential weapons of bioterrorism.
Sandia wanted to work with UTMB because it is a leading institution in infectious disease, an area in which Sandia does not have much expertise, said Singh. Sandia’s group is working closely with Allan Brasier, an associate professor of biochemistry and molecular biology, whose lab looks at how inflammatory signaling controls gene expression.
In terms of infectious disease and the collaboration with UTMB, Singh mentioned that the goal there is to make a miniaturized benchtop system in about two years and place it in UTMB’s Biosafety Level 3 and 4 labs. The device can then be used to study immune response to highly pathogenic organisms.
According to UTMB, it first joined forces with Sandia two years ago. A jointly funded postdoctoral program has since been established, and four inaugural fellowships were awarded last February to collaborative Sandia-UTMB teams.
“We are also trying to form partnerships with clinical labs and medical schools to apply this technology to other areas of research that involve cell signaling,” Singh said. For example, Sandia is talking to the University of New Mexico Medical School regarding cell signaling in the context of cancer research he noted.
Sandia is also talking with private companies involved in vaccine development about using cell-based assays to screen potential vaccine targets, said Singh. He declined to provide additional details. Sandia is also contacting pharmaceutical companies about using the lab-on-a-chip platform in drug discovery.