July 2, 2015Imagine a large haystack piled before you. Now imagine being asked to search for one or two teeny tiny needles in that haystack. The analogy of a needle in a haystack may be a bit clichéd, but that is exactly the problem that often faces students and faculty who endeavor to go through the process of sorting cells. Without modern technologies, the process of separating certain cells from a culture for research could be very time-consuming. And for some studies, such as the work Ph.D. student Ali Adem Bahar is doing with persister cells, it couldn’t be done at all. The cells he’s looking for make up such a small percentage of the cells in his samples that the exercise of sorting cells is very much like searching for a needle in a haystack. Funded by the National Science Foundation,a team led by Professor Dacheng Ren acquired a BD Special FACSAriaTM cell sorter for the new Syracuse University Flow Cytometry and Cell Sorting Core Facility to promote cutting-edge research by automatically sorting cells with high efficiency and accuracy, even if they appear in low percentages. The persister cells that Bahar is researching are found in chronic infections. They are highly resistant to antibiotics and are what cause certain infections to be incurable. In order to best examine these cells, he requires that they be separated from the other cells in his samples. Today, when Bahar and students like him need to sort the cells in a sample, they reach out to Grace Altimus, the flow core operator in the Flow Cytometry and Cell Sorting Core Facility. Bahar preps his cell culture appropriately and delivers his liquid sample, labeled with a bright orange biohazard sticker, to Altimus. Once loaded into the equipment, cells from Bahar’s sample are sucked in and passed one-by-one through four laser beams that cause each cell to reveal certain properties that the machine uses to classify and sort them. Combined with the negative pressure biosafety hood that it resides in, it is an imposing, noisy piece of equipment, but it works expeditiously to accomplish its task. The entire process takes only an hour, and in the end, Bahar is able to study a useful set of persister cells. The sorted cells can be analyzed, and in some cases, even cultured.“It’s helping my research greatly. There are certain things that we were forced to assume about persister cells, but there was no way to prove that we were correct. With this equipment, we can do that now. This machine has pushed the boundaries of our research,” said Bahar. In addition to the BD Special FACSAriaTM cell sorter, the facility features a BD AccuriTM C6 flow cytometer. Both instruments are new and capable of processing a variety of samples, including those designated biosafety level II. The experience is extended to undergraduate students in the bioengineering program as part of their coursework. In the Biological Principles for Engineers course, students conduct laboratory exercises using the cell sorter and flow cytometer, providing them with firsthand experience in molecular cloning, DNA isolation, and antibiotic resistance. “The flow core facility provides a unique opportunity to foster research collaboration and innovative teaching and outreach, which will significantly benefit the students of Syracuse University,” said Ren.