Spotted salamanders are unique among vertebrates, in that they're the only ones whose embryos have an algae living inside of them. Scientists are now hoping that a better understanding of this symbiotic relationship could lead to new drugs for humans.
For some time now, it has been known that when the spotted salamander (Amblystoma maculatum) lays its eggs in aquatic environments, those eggs are harmlessly infiltrated by a green algae known as Oophila amblystomatis. This can actually be seen in the green coloration of the egg clusters.
It's a win/win scenario, as the algae feed upon nitrogen-rich waste produced by the embryos, while the embryos benefit from the waste removal and the oxygen produced by the algae. More recently, however, it was found that algal cells actually make their way into tissue cells throughout the embryos' bodies.
That discovery has led to a new study, led by senior research scientist John Burns of Maine's Bigelow Laboratory for Ocean Sciences.
Among other things, the researchers are intrigued by the fact that the algal cells appear to avoid rejection by activating genes that suppress the immune response within the embryos. It is hoped that if the mechanism by which the cells do so can be more fully understood, it could lead to medications for safely treating autoimmune diseases in humans.
Additionally, the scientists are investigating the possibility that the presence of the algae in the embryos may play a role in the salamanders' lifelong ability to regrow limbs and tails. If that turns out to be the case, then drugs derived from the algae may someday find use in human tissue repair therapy.
"When we look to the natural world for drugs, we are usually looking at antagonisms. We're looking for the kind of thing that stops bacteria from growing in order to find something we might be able to use in our own bodies," says Burns. "Studying these organisms in a symbiotic relationship is completely new, and that's why we think it's an interesting place to look for new types of drugs."
The three-year research project also involves scientists from the University of North Carolina Wilmington and Pennsylvania's Gettysburg College.
