A team of
researchers from the Institute of Bioengineering and Nanotechnology
at the Agency for Science, Technology and Research (A*STAR) has
worked to develop an efficient technology that uses DNA to detect and
treat infectious diseases. Improving upon an existing method, the
research makes use of single-stranded DNA molecules called aptamers,
and it could be used to treat cancer.
Aptamers are good candidates for the development of new treatments, as they have an innate ability to bind to any molecule they're targeted at, including cancer cells and bacteria. Once bound to a target, the aptamer inhibits its activity, eliminating the threat it poses to the host.
While aptamers are useful for both detecting and treating dangerous conditions, they suffer from two issues that stop them from being as effective as they could be. Firstly, the bonds they form with target molecules are usually too weak to be effective, and they're easily digested by enzymes. These two problems have been a barrier to getting aptamers approved for clinical use.
The A*STAR researchers decided to tackle these exact problems. Firstly, they added an artificial component, referred to as an unnatural base, to a standard aptamer, increasing its ability bind to target molecules. A second addition was then made in the form of a small DNA, known as mini hairpin DNA. With a particularly stable and compact structure, the component is very resistant to digestion, allowing the aptamer to reside in the system for days instead of hours.
With the two major issues with DNA aptamers addressed, it's possible that they could one day replace antibodies for disease targeting. Antibodies bind to their targets in the same way as aptamers, but unlike the pioneering DNA technology, they can give rise to undesirable immune responses, and aren't as easy to produce in large quantities at high quality.
"Our aptamers are more efficient, and lower in cost and toxicity compared to conventional methods," said team member Dr Hirao. "The next step of our research is to use the aptamers to detect and deactivate target molecules and cells that cause infectious diseases, such as dengue, malaria and Methicillin-resistant Staphylococcus aureus, as well as cancer."
The findings of the work were published in the journal Scientific Reports.