For the first time ever, scientists have successfully grown non-mammalian skin in the lab. Belonging to that of the endangered green sea turtle, the researchers hope to use the reconstructed skin in order to understand how certain cancers form tumors on the reptiles’ skin, which can ultimately be fatal.
The green sea turtles that swim in the warm waters surrounding Hawaii, Florida, and Brazil have been suffering from a prolific tumor-forming disease specific to marine turtles. Known as fibropapillomatosis, it forms massive benign growths and tumors that tend to develop around the eyes, mouth, and neck, as well as sometimes forming internally. While the tumors themselves don’t kill the infected animals, they can become so big that they obstruct the eyes and block the throat.
The tumors are thought to be caused by a turtle-specific herpesvirus called chelonid herpesvirus 5 (ChHV5), and it is considered to be spread through turtle leeches as they feed from turtle to turtle. It is found worldwide, but is far more common in warmer waters, infecting over 50 percent of some populations. Scientists have known about the virus for about two decades, but their inability to grow it in the lab has hampered research and the development of blood tests to detect it.
The researchers hope that by being able to grow turtle skin in the lab, they can now start to understand how and why the herpesvirus is able to infect the animals, and what makes it so prolific. The results are published in the Journal of Virology.
“Fibropapillomatosis is the most common infectious disease affecting endangered green turtles,” explains the United States Geological Survey’s Thierry Work, who led the latest research, in a statement. “Our findings provide a significant advancement in studying FP, and may eventually help scientists better understand other herpes virus-induced tumor diseases, including those of humans.”
They were able to take cells from ChHV5 tumors and cells from healthy turtle skin, and then reconstruct the skin's three-dimensional structure in the laboratory. This is not only the first time that a team has managed to grow reptile skin in the lab, but also the first time that anyone has successfully managed to grow non-mammalian skin in the lab.
The researchers were then able to take slices of the infected skin that was grown and see exactly how the virus replicates. They found that the ChHV5 created bizarre replication “centers”, which formed within the turtles' own cells, before bursting out and infecting new ones.
The team hope their work will inform other questions about how viruses infect reptiles, and may even help to answer questions about herpes virus-induced tumors in humans.