Researchers report they have succeeded in growing mature taste receptor cells outside the body and have been able to keep the cells alive for a prolonged period, according to an online issue of Chemical Senses.
Researchers from the Monell Chemical Senses Center, Philadelphia, obtained basal cells from rat taste buds and placed these cells in a tissue culture system containing nutrients and growth factors. In this environment, the basal cells divided and differentiated into functional taste cells.
The new cells, which were kept alive for up to two months, were similar to mature taste cells in several key respects. The researchers used a variety of methods to show that the cultured cells contained unique marker proteins characteristic of mature functioning taste receptor cells. Also, functional assays revealed that the cultured cells responded to either bitter or sweet taste stimuli with increases of intracellular calcium, another property characteristic of mature taste cells.
"Although scientists have tried for many years to maintain taste cells in a long-term culture system, it was commonly believed that these cells could not be kept alive for longer than about 10 days," said lead author Hakan Ozdener, MD, PhD. "Now, we have demonstrated that taste cells can be generated in vitro and maintained for a prolonged period of time."
By using the cultured taste cells, researchers have more precise control over the cell’s surrounding environment, as well as better access to subcellular mechanisms, allowing them to ask questions that previously could not be addressed.
Cultured cells can be used to study how taste stimuli interact to enhance good tastes or suppress unpleasant tastes. Similarly, new molecules, including potential artificial sweeteners or bitter blockers, can be evaluated to determine if they interact with taste receptors to activate the cell.
Another important area of research is helping people who have lost their sense of taste as a result of irradiation or diseases. Identification of factors that promote taste cell regeneration and growth may provide new avenues of treatment.
Although the current experiments used rat taste cells, the researchers intend to use taste cell biopsy specimens from humans to try to grow human taste cells.
This study was supported by grants from the National Science Foundation and the Givaudan Flavors Corporation.
