Source: Tyler Schwend, 785-532-6553, tschwend@k-state.edu
News release prepared by: Stephanie Jacques, 785-532-0101, sjacques@k-state.edu

Monday June 13, 2011

PROMISING START: POSTDOC'S EYE RESEARCH EARNS AWARD FROM NATIONAL INSTITUTES OF HEALTH

MANHATTAN -- A Kansas State University postdoctoral fellow is being recognized by the National Institutes of Health as a promising young scientist.

Tyler Schwend, a research associate with K-State's Division of Biology, has received the $50,000 Dawn Kirschstein National Research Service Award from the National Institutes of Health, National Eye Institute.

The award provides support for promising young scientists currently engaged in scientific and health-related research as postdoctoral fellows. Schwend, who works in the lab of Gary Conrad, university distinguished professor of biology, is investigating the role of Robo-Slit signaling on avian cornea innervation during embryonic development.

Robos are the receptors for the Slit family of repellent nerve guidance cues; interactions between these two proteins can negatively influence nerve outgrowth or repel nerve growth away from a certain tissue. Studying corneal nerves is important because many patients who have had surgery on their cornea experience nerve regeneration that is slower than expected, and Schwend believes it may be due to the Robo-Slit interaction.

"Through conversations with clinicians we have learned that nerves grow back extremely slowly after corneal surgery, such as with LASIK or cornea transplantation. It can take many months to a couple of years, and in some rare cases they may not grow back at all," Schwend said.

The cornea is the most densely innervated tissue on the surface of the body and its network of nerves are crucial for the well-being of the eye, Schwend said. A delay in nerve regeneration increases the risk of further trauma to a patient's eye and vision because the nerves in the cornea are important for sensing pain and other noxious stimuli from the environment, which increase the need for tear production and a blinking reflex as a means of protection. The Robo-Slit interaction, found to be essential during embryonic development of the eye, likely prevents nerves from entering the cornea until development has reached a certain point. Similar interactions could be the cause of the delay in regenerating nerves in adults.

Schwend is studying the embryonic development of the eye in chickens. He alters the Robo-Slit interaction, adding a recombinant protein that mimics Robo and binds to Slit. This prevents the real Robo protein from binding and influencing nerve growth and path finding.

"As a developmental biologist, I'm always wanting to set up a functional study where I can either over-express a particular protein by giving the body or a tissue too much of it, or take that particular protein away," Schwend said. "Then I ask, 'OK, what happened to normal development?' I wanted to see what happens when I take the Robo-Slit interaction, a potentially vital one, away during eye development."

In preliminary tests, Schwend has discovered that when the Robo-Slit interaction is prevented, nerves may grow into the cornea earlier but will be highly disorganized. Therefore, Schwend believes that the Robo-Slit interaction is important for nerves to precisely pattern themselves around the cornea and enter the cornea at the exact time the cornea is ready for them.

"Ultimately we hope this research will tell us how the nerves get into the cornea during development, and perhaps we can come up with a way, for a short time, to remove some of these proteins that may be slowing down regeneration in adult corneas," Schwend said.

The award is renewable for three years, at $50,000 a year, allowing Schwend to continue his research on the cornea and travel to conferences that will further his communications with clinicians and other scientists.

Schwend, Washington, Ill., earned a bachelor's in biology in 2003 from the University of Illinois at Urbana-Champaign and a doctorate, with an emphasis in cellular and molecular development biology, in 2009 from Northwestern University, Chicago, Ill.