Stem cells that could restore sight and hearing have been discovered in an experiment that has been performed successfully in animals. But according to two teams of scientists, it is an important step which will lead to future applications in humans.
A team from the Chonnam National University of South Korea was able to restore hearing in guinea pigs whose hearing was destroyed by chemical substances, using mesenchymal stem cells taken from human bone marrow. Other researchers at SUNY Upstate Medical University of Syracuse in the United States were able to restore sight in frogs using skin stem cells implanted into embryos.
Both groups of scientists revealed how “at the moment it is not possible to translate the results that they have achieved using animals into humans.
But the experiments were useful in shedding light on biological mechanisms that control sight and hearing, indicating new possibilities in regenerative medicine.” Anand Swaroop, a stem cell expert from the National Institute of Health in the United States also commented positively on the research saying that “the results are proof of the enormous potential offered by stem cells to cure mortal or debilitating diseases.”
Korean researchers cultured human bone marrow stem cells inside of nervous cells in the lab, and then transplanted them into the ear of guinea pigs. Three months after the operation, the animals showed that they had reacquired hearing, told the experiment’s coordinator during a conference of the Society of Neuroscience.
“Stem cells were able to rebuild the thin ciliated cells that are essential for hearing in mammals.” But, admitted Sujeong Jang, “we still do not know how it happened.” The discovery is important because ciliated cells, once killed by sound, chemical substances, or autoimmune attacks, do not grow back and result in a loss of hearing.
Scientists in the U.S. used skin stem cells to restore sight in frogs. To obtain their results, they added totipotent cells with seven genetic factors which forced them to turn into cells of the eye. They were then transplanted into frog embryos, restoring their vision.