Dr Kathy Muirhead – teacher, researcher, pioneer

05 February 2016, International visits and visitors

Guest Flow Cytometry expert Dr Kathy Muirhead, Adjunct Professor at Thomas Jefferson University in Philadelphia, says that the Malaghan Institute’s Kylie Price is a fourth generation flow cytometry leader carrying on the field’s tradition of sharing expertise and technology advancements with researchers seeking to understand how cells grow and interact.  First generation technology such as the “Coulter Counter” (patent filed by Wallace Coulter in in 1949), enabled automated counting and sizing, initially only of red blood cells.

Kathy first encountered flow cytometers in the 1970s, becoming a second generation developer of methods and applications as the technology moved from being a biophysicist’s curiosity to a biomedical research tool. Although her formal training was as a chemist, after which she expected to become a university professor, she says that her career path took a different direction because flow cytometry combined her love for learning new things and her facility for “translating” across disciplines.

While Dr Muirhead was working as a post doc at the University Of Rochester School Of Medicine in the 1970s she says, “Several different technologies came together to create commercial instruments able to make very rapid measurements on individual cells tagged with fluorescent dyes as they went streaming through a microscopic nozzle. Even better, cells of interest (as defined by the colours of their tags) could then be recovered for further study by incorporating them into liquid droplets and using then-new ink jet printer technology to divert those droplets into a test tube.  At the same time newly developed hybridoma antibody technology provided a way to reproducibly make much purer and more specific antibodies with which to tag the cells.”

She notes that, “Taken together, these advancements revolutionized the ability of medical researchers to ask more quantitative questions about their biology of interest rather than to just qualitatively describe how the cells looked in the microscope.  ‘If we make a controlled change to a group of cells, do they all behave in the same way? Or are there rare ones that behave differently but that couldn’t be detected by traditional biochemical measurements made on the total cell population?’ While static microscopy could then, and still does, provide a lot of information about individual cells, those rare ones are likely to be missed because it is simply too time consuming to look at large numbers of cells.  Flow cytometry allowed researchers to find them, recover them and study them, and it had a huge impact on our understanding of how the immune system works.” 

Dr Muirhead says that designing, measuring and interpreting the patterns of colours measured by the flow cytometer is how the flow cytometrist deciphers biology. The reporter molecules on the outside, and the inside, of the cell tell us a great deal about what the cell is doing and its interactions with others.  While at the Malaghan she shared her experience in interpreting how extensively cells have divided based on staining them with stable low toxicity dyes, some of which she helped to discover and characterize.

Dr Muirhead’s four and a half decades of practical experience with a technology that has become synonymous with medical research and clinical diagnosis, is complemented by a career spanning academia, teaching, work in pharmaceutical research and a bio-medical start-up.  She also co-created several online cytometry education training modules on cell proliferation for the CYTO University initiative of the International Society for Advancement of Cytometry and consults on applications for US$1billion  Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs which are one of the largest sources of early-stage capital for innovative small companies in the United States. Her assistance helps applicants – whose success rate is typically 10-15% – bump up to 50 or 60% success.

Malaghan staff scientists, and a handful of external researchers, have had her “lessons learned the hard way” and natural teaching abilities at their disposal during the first week of February as they workshop different methods of measuring cell proliferation.