Biotech Startup Granted $1.65M for 'Molecular Beacon'

A company co-founded by a Georgia Institute of Technology researcher has received a $1.65 million federal grant to develop and commercialize a nanoscale sensor called a “molecular beacon” for the detection and diagnosis of diseases including cancer.

A molecular beacon is a hairpin oligonucleotide (a short sequence of RNA or DNA nucleotides) probe that fluoresces upon binding to a target RNA molecule.

The funding -- a Small Business Technology Transfer Program (STTR) Phase II grant from the National Cancer Institute -- provides $1.65 million over two years to Vivonetics, a startup company founded by Gang Bao and Karim Godamunne. Bao, a professor in the Wallace H. Coulter Department of Biomedical Engineering operated jointly by Georgia Tech and Emory University, will lead the Vivonetics/Georgia Tech research team.

Researcher Gang Bao with a confocal microscope used to image molecular beacons in cellular samples. Vivonetics, a startup company he co-founded, recently won a $1.65 million grant from the National Cancer Institute. (Georgia Tech Photo: Gary Meek)

“The funding will be used for two purposes -- to further develop our key technology and to commercialize that technology,” said Bao. “We hope to be able to launch a product by May 2007.”

Vivonetics, founded in 2003, also received an earlier STTR Phase I grant for $30,000 and two Georgia Research Alliance grants totaling $118,000 through VentureLab, a Georgia Tech unit that supports commercialization of research discoveries.

The company's core technology is called Dual FRET molecular beacons, which uses fluorescence resonance energy transfer with a pair of molecular beacons to significantly reduce background signals and increase detection sensitivity. Dual FRET molecular beacons are a key advance in molecular beacons technology for detecting specific genetic sequences in living cells.

When molecular beacons are delivered into human cells, they seek out matching sequences in genetic material known as messenger RNA (mRNA). If the beacons encounter and bind with their mRNA targets, they emit specific fluorescent signals when excited by light.

However, enzymes and other molecules inside a living cell could cause a beacon to open and emit a false-positive signal. For early cancer diagnosis and other biological studies, researchers must develop a detection system sensitive enough to distinguish between true and false-positive signals.

To do this, the Dual FRET molecular beacons approach uses two molecular beacons -- one with a donor dye, the other with an acceptor dye -- that form a FRET pair. Binding of the beacon pair with the same mRNA causes the beacons to open, setting off an energy transfer from the donor dye to the acceptor dye that provides a specific signal when stimulated by light. This distinctive signal could significantly reduce false-positive readings.

“Initially our products will be aimed at detecting cancer genes for research use only,” said Dennise Dalma-Weiszhausz, Vivonetics’s general manager. “Our hope is that, over time, we can get our technology to a point where it can be used by pharmaceutical companies to develop new drugs, and as a diagnostic tool after receiving FDA approval.”

Currently, she said, diagnosis of breast cancer in lymph nodes requires pulverizing an excised node and then estimating the amount of cancerous genetic material. By contrast, Dual FRET molecular beacons can detect individual cancerous cells in a lymph node, allowing earlier and more accurate detection of metastasis.

Dual FRET molecular beacons technology will be used initially to evaluate material taken from the human body. But Bao’s team is also working on techniques that would allow future products to be used inside a patient’s body. For such in vivo use, researchers will have to show that the probes don’t harm healthy cells.

Bao envisions a comprehensive system in which molecular beacons would detect cancerous cells in lab-tested bodily fluids. When fluids couldn’t be obtained, other probes would be introduced into the body to detect cancerous cells. Moreover, these probes could be used to monitor the success of cancer therapy.

And because they attach specifically to mRNA, beacons with a proper design might someday be used to slow or halt cancer-cell growth.

Dual FRET molecular beacons also have the capability to detect viral infection rapidly -- in hours rather than days. That could allow the technology to become an asset against infectious disease outbreaks and bioterrorism. For more information, visit: www.gatech.edu