Lasers in medicine

Scientists in Scotland are developing new studies into how the latest laser trapping methods can assist in the safe and non-destructive delivery of therapeutic molecules into cells, which may lead to new, improved methods for drug delivery.

The techniques could have potential benefits for a range of medical applications such as gene therapy, the delivery of anti-cancer agents and the destruction and removal of arterial plaques, one of the causes of heart attacks and strokes.

Dr Kishan Dholakia of the University of St Andrews’ School of Physics and Astronomy is collaborating with Dr Paul Campbell of the University of Dundee ‘s Department of Surgery and Molecular Oncology at Ninewells Hospital to develop new and safer ways of delivering molecules, such as DNA, into cells. Therapeutic DNA product is delivered into the nucleus of diseased / dysfunctional cells to ‘re- program’ the functionality to mimic that of healthy counterparts.

In particular, they will investigate the process of ‘sonoporation’ – the method of using ultrasound waves to permeabilise the cell membrane when delivering molecules into cells. Currently the mechanisms behind the sonopration process are not well understood – something the St Andrews and Dundee researchers are hoping to change.

Over the next 3 years, they will further investigate this process, thanks to a recent £354,000 grant from the EPSRC (Engineering and Physical Sciences Research Council).

The project will involve an exciting blend of cutting edge laser trapping methods developed by Dr Dholakia, Professor Wilson Sibbett and Dr Mike MacDonald of the Optical Trapping Group at St Andrews, with world leading work of the Ninewells group and promises a great future for controlled and directed delivery of molecular agents into cells.

“The key to future biomedical applications is the introduction of foreign DNA into the cell whilst keeping the cell’s architecture intact. The ability to achieve this without any electrical, mechanical or chemical means would realise both an attractive and powerful tool,” said Dr Dholakia.

“Sonoporation represents the most appropriate route to the implementation of delivering therapeutic DNA, such as chemo or gene-therapies, into a cell. This involves using ultrasound and contrast agents (bubbles) placed close to the cell. Applying ultrasound to the system causes tiny perforations in the cell membrane to appear allowing the required DNA to enter.

“Turning off the ultrasound means the membrane closes up and is left intact. However, as the fundamental mechanism of sonoporation remains elusive, the main aim of the project is to understand the mechanism via a series of experiments.

“Crucial to the experiments is an ability to control the absolute displacement between distinct bubbles and biological cells, which will be accomplished using an enhanced laser optical tweezing facility based on an existing set-up at the University of St Andrews,” he said.

Dr Campbell, a physicist working with Professor Sir Alfred Cuschieri’s Surgical Technology group at Ninewells, said:

“Sonoporation has promise for implementation on a clinical scale, making it practical as well as cheap since it uses standard hospital equipment, and with no incision wound to address the surgical area, it causes no trauma to the patient. ”

ENDS

NOTE TO EDITORS:

DRS DHOLAKIA AND CAMPBELL ARE AVAILABLE FOR INTERVIEW TODAY ON 01334 463184 AND 01382 496490 RESPECTIVELY.

Issued by Beattie Media On behalf of the University of St Andrews Contact Gayle Cook on 01334 467227, mobile 07900 050103, or email [email protected] Ref: Dholakia Ninewells grant pr 070902 View the latest University news at http://www.st-andrews.ac.uk