“At two months, on immunohistochemistry, nearly all of the animals at this point were demonstrating evidence of partial reinnervation of the adductor complex,” Dr. Halum said. At four months, there was less of a difference on laryngeal electromyography, but there was a different story in the immunohistochemistry evaluation; the team found that eight of the stem-cell treated animals had over 66 percent motor endplates with nerve contact.
The findings could be a launching pad for further use of neurotrophic factor with stem cells, Dr. Halum said. “The study really just serves as a proof of concept,” she said. “It proves that we can have efficient selective delivery of neurotrophic factor with our stem cell vectors. We found a wide variety of spontaneous reinnervation patterns that were enhanced with the stem cell-treated animals.”
Dr. Halum said that in the future, clinicians may be able to use these stem cell techniques to adjust vocal cord position. “In fact, as new investigators are coming out with ways of developing a tissue-engineered larynx, neurotrophic factor-secreting stem cells could readily be incorporated to guide and direct reinnervation,” she said.