Researchers at the University of
Central Florida (UCF) have developed a novel technique that may give doctors a
faster and more sensitive tool to detect pathogens associated with inflammatory
bowel disease, including Crohn’s disease.
The new nanoparticle-based technique
also may be used for detection of other microbes that have challenged
scientists for centuries because they hide deep in human tissue and are able to
reprogram cells to successfully evade the immune system.
The microbes reappear years later and
can cause serious health problems such as seen in tuberculosis cases. Current
testing methods to find these hidden microbes exist, but require a long time to
complete and often delay effective treatment for weeks or even months.
UCF Associate Professor J. Manuel
Perez and Professor Saleh Naser and their research team have developed a method
using nanoparticles coated with DNA markers specific to the elusive pathogens.
The technique is effective and more accurate than current methods at picking up
even small amounts of a pathogen. More important, it takes hours instead of
weeks or months to deliver results, potentially giving doctors a quicker tool
to help patients.
“Our new technique has surpassed
traditional molecular and microbiological methods,” said Naser, a professor at
the UCF College of Medicine. “Without compromising specificity or sensitivity,
the nano-method produced reliable and accurate results within hours compared to
months.”
The group’s translational research
works is published in PLoS
ONE.
The team created hybridizing magnetic
relaxation nanosensors (hMRS) that can fish out and detect minuscule amounts of
DNA from pathogens hiding within a patient’s cells. The hair-thin hMRS are
composed of a polymer-coated iron oxide nanoparticle and are chemically
modified to specifically bind to a DNA marker that is unique to a particular
pathogen.
When the hMRS bind to the pathogen’s
DNA, a magnetic resonance signal is detected, which is amplified by the water
molecules that surround the nanoparticle. Then the researcher can read the
change in the magnetic signature on a computer screen or portable electronic
device, such as a smartphone, and determine whether the sample is infected with
a particular pathogen.
The researchers used Mycobacterium avium spp. paratuberculosis
(MAP), a pathogen that has been implicated in the cause of Johne’s disease in
cattle and Crohn’s disease in humans, to test out their technique. They used a
large number of blood and biopsy tissue samples from patients with Crohn’s
disease and meat samples from cattle with Johne’s disease.
“It is all about giving medical
professionals easy and reliable tools to better understand the spread of a
disease, while helping people get treatment faster,” said Perez, who works at
UCF’s Nanoscience Technology Center. “That’s my goal. And that’s where
nanotechnology really has a lot to offer, particularly when the technology has
been validated using clinical, food and environmental samples as is in our
case.”
The National Institute of General
Medical Sciences (NIGMS), which is a part of the National Institutes of Health,
and funded the research, said this kind of basic research can provide the
foundation for medical breakthroughs.
“Just last year, Dr. Perez and his
team unexpectedly discovered the DNA binding property of their magnetic nanosensors,
and now they have shown that it may become the basis for a rapid, sensitive lab
test for hard-to-measure bacteria and viruses in patient samples,” said Janna
Wehrle, PhD, of NIGMS. “This is a wonderful example of how quickly an advance
can move from the research bench to meet an important clinical need.”
