Purdue researchers create templates on retinal tissues

December 05, 2003

WEST LAFAYETTE, Ind. - Researchers at Purdue University have created scaffold-like patterns on the surface of a pig's retina, making templates out of molecular compounds called peptides that could promote the growth of transplanted healthy cells to treat age-related macular degeneration.

Macular degeneration destroys light-sensing cells in the retina. Researchers at other institutions have hypothesized that placing templates on the retina could enable transplanted cells to take hold and grow.

Biomedical engineers at Purdue used an instrument called an atomic force microscope and a device called a cantilever to lay down lines of peptides in a process known as dip-pen nanolithography. The pattern was permanently attached to a dime-size piece of retina extracted from the eye of a pig, said Albena Ivanisevic, an assistant professor of biomedical engineering and an assistant professor of chemistry at Purdue. The work was not done with live pigs.

"We wanted to demonstrate that we could perform lithography, or patterning, on something other than a metal, semiconductor or insulator surface," Ivanisevic said. "Here we have shown that it can be done on retinal tissue."

Ivanisevic detailed findings in a talk presented Dec. 3 during a meeting of the Materials Research Society in Boston.

"We are interested in making surfaces that can eventually be used for transplant strategies," Ivanisevic said. "It has been proposed that you might implant retinal pigment epithelial cells as a potential treatment for macular degeneration, but the success of such a procedure could be greatly increased if you used some sort of a template or scaffold."

Peptides are made of amino acids, the building blocks of proteins.

The Purdue engineer conducted tests demonstrating that the templates were permanently attached to the retinal tissues, but further work is needed to determine the precise nature of the bonds created and to fashion templates out of various types of peptides.

"The idea is to generate different types of patterns on the surface and test whether they indeed promote the proliferation of retinal pigment epithelial cells and how the surface arrangement of these molecules on the surface affects that," Ivanisevic said.

Each of the lines in the template was less than 100 nanometers wide. "Nano" is a prefix meaning one-billionth, so a nanometer is one-billionth of a meter, or roughly the length of 10 hydrogen atoms strung together.

Macular degeneration is an incurable eye disease that is the leading cause of blindness for people 55 and older in the United States, affecting more than 10 million Americans. Retinal pigment epithelial cells deliver nutrients to the retina and remove waste products. Macular degeneration is caused by a deterioration of these cells.

The research paper was written by Ivanisevic and visiting student Nicole Onyenenho from the University of Maryland.

Ivanisevic is associated with two centers in Purdue's Discovery Park: the Birck Nanotechnology Center and Bindley Bioscience Center, which funded the research, and this work also is supported by the NASA Institute for Nanoelectronics and Computing at Purdue.
Writer: Emil Venere, 765-494-4709, venere@purdue.edu

Source: Albena Ivanisevic, 765-496-3676, albena@purdue.edu

Related Web sites:
Albena Ivanisevic: https://engineering.purdue.edu/BME/People/viewPersonById?resource_id=2251
Materials Research Society: http://www.mrs.org

Purdue University

Related Macular Degeneration Articles from Brightsurf:

Levodopa may improve vision in patients with macular degeneration
Investigators have determined that treating patients with an advanced form of age-related macular degeneration (AMD) with levodopa, a safe and readily available drug commonly used to treat Parkinson's disease, stabilized and improved their vision.

Combating drug resistance in age-related macular degeneration
An international team of researchers led by Baylor College of Medicine and Houston Methodist has discovered a strategy that can potentially address a major challenge to the current treatment for age-related macular degeneration,

Study finds unexpected suspect in age-related macular degeneration
Scientists have identified an unexpected player in the immune reaction gone awry that causes vision loss in patients with age-related macular degeneration (AMD), according to a new study published today in eLife.

Potential way to halt blinding macular degeneration identified
It would be the first treatment for dry age-related macular degeneration and could significantly improve treatment for wet AMD.

Heating techniques could improve treatment of macular degeneration
Age-related macular degeneration is the primary cause of central vision loss and results in the center of the visual field being blurred or fully blacked out.

Eye's vulnerability to macular degeneration revealed
Scientists have found significant differences in the shape and biology of the same type of cell taken from different parts of the retina, according to a study in eLife.

Hallucinations associated with brain hyperactivity in people with macular degeneration
New research from The University of Queensland has shown for the first time that visual hallucinations in people with macular degeneration are associated with abnormally heightened activity in the visual cortex of the brain.

Eating leafy greens could help prevent macular degeneration
A new study has shown that eating vegetable nitrates, found mainly in green leafy vegetables and beetroot, could help reduce your risk of developing early-stage age-related macular degeneration (AMD).

An orange a day keeps macular degeneration away: 15-year study
A new study has shown that people who regularly eat oranges are less likely to develop macular degeneration than people who do not eat oranges.

Macular degeneration linked to aging immune cells
Studying mice and cells from patients, vision researchers at Washington University School of Medicine in St.

Read More: Macular Degeneration News and Macular Degeneration Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.