Fraley nets $500K Burroughs Wellcome Fund award for microfluidics work

Stephanie Fraley (Photo: Homewood Photography)

Stephanie Fraley (Photo: Homewood Photography)

A Johns Hopkins research fellow who is developing novel approaches to quickly identify bacterial DNA and human microRNA has won the prestigious $500,000 Burroughs Wellcome Fund (BWF) Career Award at the Scientific Interfaces. The prize, distributed over the next five years, helps transition newly minted PhDs from postdoctoral work into their first faculty positions.

Stephanie Fraley is a postdoctoral fellow working with Samuel Yang, MD, in Emergency Medicine/Infectious Disease at the Johns Hopkins School of Medicine and Jeff Wang, PhD, in Biomedical Engineering with appointments in the Whiting School of Engineering and the medical school. The goal of her work is to develop engineering technologies that can diagnose and guide treatment of sepsis, a leading cause of death worldwide, while simultaneously leading to improved understanding of how human cells and bacterial cells interact.

“Sepsis is an out of control immune response to infection,” Fraley said. “We are developing tools that are single molecule sensitive and can rapidly sort and detect bacterial and host response markers associated with sepsis. However, our devices are universal in that they can be applied to many other diseases.”

Fraley is using lab-on-chip technology, also known as microfluidics, to overcome the challenges of identifying the specific genetic material of bacteria and immune cells. Her technology aims to sort the genetic material down to the level of individual sequences so that each can be quantified with single molecule sensitivity.

“Bacterial DNA is on everything and contamination is everywhere, so trying to find the ones associated with sepsis is like the proverbial search for the needle in the haystack,” Fraley said. “With microfluidics, we can separate out all the bacterial DNA, so instead of a needle in a haystack, we have just the needles.”

Another advantage to Fraley’s novel technology is that it will assess all the diverse bacterial DNA present in a sample, without presuming which genetic material is important. “Bacteria are constantly evolving and becoming drug resistant,” she said. “With this technology, we can see all the bacterial DNA that is present individually and not just the strains we THINK we need to look for.”

Fraley’s award will follow her wherever her career takes her. The first two years of the prize fund postdoctoral training and that last three years help launch her professional career in academia. During the application process, she had to make a short presentation on her proposal to BWF’s panel of experts. “It was like the television show ‘Shark Tank’ but for scientists,” she laughs. “ The panelists gave me many helpful suggestions on my idea.”

Fraley earned her bachelor’s degree in chemical engineering from the University of Tennessee at Chattanooga and her doctorate in chemical and biomolecular engineering with Denis Wirtz, professor and director of Johns Hopkins Physical Sciences-Oncology Center. Wirtz is associate director for the Institute for NanoBioTechnology and Yang and Wang also are INBT affiliated faculty members.

BWF’s Career Awards at the Scientific Interface provides funding to bridge advanced postdoctoral training and the first three years of faculty service. These awards are intended to foster the early career development of researchers who have transitioned or are transitioning from undergraduate and/or graduate work in the physical/mathematical/computational sciences or engineering into postdoctoral work in the biological sciences, and who are dedicated to pursuing a career in academic research. These awards are open to U.S. and Canadian citizens or permanent residents as well as to U.S. temporary residents.

Micro- and nano-technologies can be used for better molecular diagnostics

Jeff Wang of Johns Hopkins at the annual INBT NanoBio Symposium. Photo by Mary Spiro

Even the smallest mutations in the human genome can be linked to the development of many diseases. Jeff Tza Huei Wang is an associate professor of mechanical engineering at Johns Hopkins University with joint appointments in biomedical engineering and oncology at the Johns Hopkins School of Medicine. He presented a talk at INBT’s annual NanoBio symposium on May 4 that focused on “breaking the barrier from bench to bedside processing” with techniques on the nano and micro scale with high sensitivity and throughput at a low cost.

Quantum dots are an attractive option for ultra sensitive detection of molecules on the nanoscale, Wang said. Wang has developed DNA functionalized quantum dots with the ability of detecting DNA mutations down to levels as low as 10-12 grams.

Methylation of DNA, which is an epigenetic or outside of the genetic code alteration to DNA, can silence genes important in tumor suppression. These quantum dots can also be designed to detect methylation in tumor precursors, which would allow for early detection of cancerous cells in the body.

Polymerase chain reaction (PCR) is a technique used in diagnosis of many diseases and infections like HIV and cancer by creating thousands of copies of DNA from a single DNA sample that can then be screened to find disease-related mutations in cells. This typically must be carried out in a lab and can take weeks to process, but Wang has developed a lab on a chip microfluidic device that can carry out this whole process.

Microdroplets in oil are used as reaction vessels for each stage and super paramagnetitic nanoparticles are able to guide the DNA from droplet to droplet. This device would allow for PCR analysis to happen at a patients’ bedside within a matter of minutes.

Story by Gregg Duncan, a Ph.D. student in the Department of Chemical and Biomolecular Engineering with interests in biomaterials and drug delivery.