From mom's comforting croon to a shout of warning, our voices are the main way we communicate and one we take for granted unless something goes wrong. Now researchers have grown human vocal cords in the laboratory that appear capable of producing sound — in hopes of one day helping people with voice-robbing diseases or injuries.

Your voice depends on tiny but complex pieces of tissue that must be soft and flexible enough to vibrate as air moves over them — the way they make sound — but tough enough to survive banging together hundreds of times a second.

Researchers at the University of Wisconsin-Madison reported the first lab-grown replacement tissue that produced some sound when tested in voice boxes taken from animals.

Dr. Nathan Welham, who led the work published in Science Translational Medicine, said, "This lends promise or hope to one day treating some of the most severe voice problems that we face."

The vocal cords, what scientists call "vocal folds," sit inside the larynx or voice box, near the Adam's apple in the neck. Welham's team started with some rare donations of vocal cords from four patients who had had their larynx removed for noncancerous reasons, and from one deceased donor. The researchers culled two types of cells that made up most of the tissue, and grew a large supply of them.

Then they arranged the cells on 3-D collagen scaffolding, and the two cell types began mixing and growing. In 14 days, the result was tissue with the shape and elasticity of human vocal cords, and with similar chemical properties.

Associated Press