Dr. Kathrin Plath: Building the Foundation for Life-Changing Discovery

Kathrin Plath appreciates the basics.

She grew up on the east side of the Berlin Wall but can’t recall going without. In her spare time she enjoys a good book, classical music and a game of tennis. At UCLA, her focus is basic science—the foundation upon which life-changing discovery is built.

“It’s exciting to come up with new questions, study them and discover the answers,” said Plath, a stem cell scientist, a member of UCLA’s Jonsson Cancer Center and an assistant professor of biological chemistry. “You find the answer, and that leads to more questions and even more answers. It’s a very dynamic, exhilarating process.”

Basic science researchers typically toil in obscurity. The discoveries built on the foundations of basic science—those with an immediate impact on the world—typically attract the headlines rather than the basic science discoveries themselves.

Yet Plath and colleagues at UCLA and Harvard recently achieved a degree of international renown when they took normal adult tissue cells and reprogrammed them into cells with the same unlimited properties as embryonic stem cells—those that can give rise to every cell type found in the body.

The work, done with mouse models, appeared in the inaugural June 2007 issue of  the medical journal Cell Stem Cell. Plath and colleagues took mouse fibroblasts, easily obtainable skin cells, and added four genes that bind to special sites on the DNA. Using this process, they turned the fibroblasts into pluripotent cells that proved nearly identical to embryonic stem cells.

The implications for disease treatment could be staggering. Reprogramming adult stem cells into embryonic stem cells could generate a potentially limitless source of immune-compatible cells for tissue engineering and transplantation medicine.

“If we can recreate this in human cells, it will have significant implications for regenerative therapies,” said Plath. “Our reprogrammed cells were virtually indistinguishable from embryonic stem cells. We could find no evidence that they were different in any way. We were rather surprised at how well this reprogramming worked.”

The level of collaboration that makes these kinds of discoveries possible attracted Plath to UCLA. The daughter of two East German scholars, she experienced the power of scientific collaboration firsthand when she left Berlin’s Humboldt University to study under the guidance of Tom Rapoport, a renowned East German scientist who had become a professor of cell biology at Harvard.

“I like the way he thinks about science. He knows all the details and enjoys discussing them,” Plath said. “He has many scientists in his lab, yet he’s really involved in the research. His approach allows him to push his science quite far.”

Her other adviser, Rudolf Jaenisch at the Massachusetts Institute of Technology, influenced Plath dramatically as well.

“He is able to envision each important step in his field and then takes the risk to move into the new direction long before others,” she said.

Since her arrival at UCLA in 2006, Plath has been developing relationships with her new mentors, Larry Zipursky, chair of biological chemistry, and Geraldine Weinmaster, a professor of biological chemistry. Both help Plath with everything from grants to managing people to scientific questions.

“The depth and variety of research interests at UCLA opens doors to all kinds of collaborative opportunities,” Plath said. “I enjoy interacting with scientists across the campus. It’s very special to have colleagues that are supportive and want to share and help. UCLA offers a very open atmosphere.”

Plath cites a conversation over coffee at UCLA with colleague Amander Clark, an expert on human embryonic stem cells.

“That conversation led to a fruitful collaboration aimed at understanding the basis of human stem cell self-renewal and differentiation,” Plath said.

With Clark and other researchers at UCLA, Plath is now trying to reprogram adult human stem cells back to an embryonic state.

She never imagined such an opportunity when she entered Humboldt University in East Germany only weeks before the Berlin wall was toppled.

“The day the wall came down was exciting,” said Plath. “Rumors were going on for a long time that something would happen. Then one night you could go over to West Berlin, go to West Germany, travel in Western Europe, then the United States. It was amazing!"

Today, the larger impact on her life is more apparent.

“Looking back at what I’ve been able to accomplish since coming to America,” Plath said. “I doubt I would have been able to do that if I would have stayed in Germany.”

By Dan Page, 2007