Dr. Jia is also collaborating with Susan Thibeault, PhD, of the University of Wisconsin in Madison, to develop a gel derived from resilin, a polypeptide isolated from insect wings. “It’s easy to mimic the viscoelastic properties of vocal folds,” said Dr. Thibeault. “We’ve been trying to load these gels with cells that can actually regenerate tissue.” Most of her recent research has focused on identifying the best type of cell to put in the gel, with emphasis on stem cells obtained from fat and bone marrow, and observing how those cells respond to vocal fold vibration.
Explore This IssueApril 2013
Regenerating Hair Cells
Not all of the research on tissue regeneration has been centered on the aerodigestive tract. At Stanford University, Stefan Heller, PhD, in the department of otolaryngology, is leading efforts to coax mouse embryonic stem cells to differentiate into inner-ear cell types, such as hair cells. “We expose the stem cells to an environment that mimics embryonic development so we can watch them grow into these inner-ear cells. Basically, we are generating ears in a culture dish,” Dr. Heller said.
Those cells reliably turn into ear structures when placed in animal embryos; unfortunately, they are accompanied by other cell types that are tumorigenic. “That’s one of the problems we have to solve before we can start transplanting the cells into animal models.”
Ultimately, Dr. Heller foresees the development medication that can be placed in the ear to stimulate hair cell regeneration. “Our target is the supporting cells, which close the gaps left when hair cells die, and form an epithelium that is rather poorly characterized at the moment. So the goal is to find ways to stimulate these cells to divide and regenerate the lost hair cells. Birds and fish do it naturally, so it’s not so far-fetched.”
Admittedly, such products are far in the future, but Dr. Heller is optimistic. “We know what the roadblocks are,” he said. “We just have to shove them away.”