All three students nodded. Despite feeling impatient, even Pia was now finding Yamamoto’s review fascinating. Like all other researchers, Pia was aware that biological science was unfolding its mysteries at an ever-increasing, mind-boggling speed. The nineteenth century had been chemistry, the twentieth physics. The twenty-first was undoubtedly going to be biology.

Yamamoto checked his own watch. As if answering Pia’s hopes, he said, “We’ve got to move this along if we’re going to catch Dr. Rothman in the organ bath unit. Let’s go back to our discussion of stem cells. Now that we have the induced pluripotent type that are going to avoid immunological rejection problems and be more acceptable to religious conservatives, what is the first step toward making them useful to treat the patient who donated the fibroblast? Anybody?” Yamamoto glanced from face to face.

Will shrugged and offered, “Get them to mature again but into the kind of cell the patient needs.”

“Thank you,” Yamamoto said. “Indeed, that is exactly what most stem cell researchers have been busy doing for years: finding out how to regulate gene expression such that the stem cells mature into the kinds of cells that make up the body, like heart cells, kidney cells, liver cells, and so forth. Stem cell researchers have now gotten very good at this, including Dr. Rothman and myself. But here is where Dr. Rothman and I have separated ourselves from the pack and are about to usher in twenty-first-century regenerative medicine that’s going to extend and improve the quality of life. We have been able to make virtual leaps in the ability to have these mature cells organize themselves into whole organs. In other words, we’ve managed to stumble on a host of structural genes and other transcriptional processes that are responsible for creating the lattice-like scaffolding that forms the basis of a three-dimensional organ. Once we had the structure, it was relatively easy to get it populated by the appropriate cells. It’s a process called organogenesis. Take, for instance, a liver. Although we and others have been able to make hepatic cells for years, we have never been able to get them to organize themselves into a whole liver with collagen, nerves, and blood vessels, the whole deal. We can do it now. We’re doing it with rapidly increasing efficiency. It’s phenomenal.”

“I assume you’ve been doing this with animal models?” Pia said.

“Of course! Mostly mice. The whole stem cell field has extensive experience with the murine model.”

“And you believe what you’ve been learning will be applicable to human cells?”

“We do, and not only on a theoretical basis. Concurrently we’ve been carrying on this research with human cells as well.” Yamamoto held up his left arm and pulled his lab coat sleeve down with his right hand. Proudly he pointed to a number of inch-long scars of varying age along his forearm. “I’ve been the guinea pig for the source of human fibroblasts. Although most of our research is done with mice, we have some human organs functioning equally well, human organs that could be used to treat me if I needed one of them. You’ll see in a few minutes. Any questions before we head over to the unit?”