Flow Cytometry Core searches out cells

CedarsScience
June 21, 2012

Imagine plucking out a single target cell from tens of thousands that flow every second through a detection chamber. That’s the magic of flow cytometers, which use fluorescence and lasers to identify and sort cells.

No wonder more than 100 researchers each month use Cedars-Sinai’s Flow Cytometry Core facilities in the Davis and Spielberg Buildings. "It is hard to find a laboratory here that is not using or planning to use cytometry for its work," said Gislâine Martins, PhD, who has directed the core since 2010. "It is a very powerful tool."

Flow cytometry involves staining cells with fluorescent dyes by using antibodies that are engineered to bind to molecules inside cells or on their surfaces. These dyes are excited by laser beams, allowing an array of detectors to analyze the cells. Depending on the model, cytometers can detect more than a dozen dye colors.

The core maintains two types of cytometers, each costing hundreds of thousands of dollars: analyzers, which examine characteristics of cell populations, and sorters, which both examine cells and physically separate them by subtype into containers. Once isolated, the cells can be functionally and molecularly analyzed or expanded in vitro to generate cell lines for research.

The core’s equipment helped a Cedars-Sinai team led by David Underhill, PhD, identify gut fungi in mice for a study published June 8 in the journal Science — one of many published studies that the core has aided.

A recent visit to the core found manager Patricia Lin sorting cardiac cells for the laboratory of Eduardo Marbán, MD, PhD, director of the Cedars-Sinai Heart Institute and the Mark S. Siegel Family Professor. Nearby, staff member Gillian Hultin sorted mouse lymphocytes for the laboratory of Moshe Arditi, MD, Cedars-Sinai executive vice-chair of research in the Department of Pediatrics and director of the Division of Pediatric Infectious Diseases, Allergy and Immunology.

The machine that Hultin was operating, a BD FACSAria III sorter made by Becton, Dickinson and Co., is so sensitive that it can isolate a single cell, Martins said. Using that capability, researchers, for instance, can find rare tumor stem cells, purify them and cultivate them for experiments.

In her own work at the Cedars-Sinai Inflammatory Bowel and Immunobiology Research Institute, where she is an assistant professor, Martins uses cytometers to sort the immune system’s T cells, which can be involved in causing intestinal disorders. She said she hopes to learn how and why some of these cells "can cross to the 'dark side' and attack tissues that they should not attack."

To serve its many users, the Flow Cytometry Core’s analyzer cytometers, which can be booked using an Internet-based calendar, are available 24/7. The core also offers consulting for users who are new to flow cytometry and need help planning their experiments. New users must register for training to ensure that they follow proper procedures, Martins said. The sorter cytometers are operated only by staff, generally from 10 a.m. to 5 p.m. Monday through Friday.

Photos (from top): Flow Cytometry Core director Gislâine Martins, PhD; manager Patricia Lin sorts cardiac cells; and staff member Gillian Hultin sorts mouse lymphocytes.