Scientists develop prototype of more sensitive test for cancer
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《英国医生杂志》
A new technology called "optical stretching" promises a simpler and more effective method of distinguishing cancer cells from their healthy counterparts.
Speaking this week at a meeting organised in Warwick by the Institute of Physics, Professor Josef K?s of the University of Leipzig described how he and his collaborator, Dr Jochen Guck, have used the technology to develop an exceptionally sensitive test for cancer.
Biologists have long known that as healthy cells undergo transformation into tumour cells their filamentous internal scaffolding or cytoskeleton becomes softer and more yielding. For this reason cancer cells are more easily deformed. Optical stretching offers a way of measuring the deformation that cells undergo when placed within narrow but powerful light beams.
The technique is a variant of what's known as the "optical tweezers." This instrument comprises a focused beam of laser light in which it is possible to trap objects the size of cells and then manipulate them. The optical stretcher invented by Professor K?s and his colleagues is a variant of this device.
Instead of a single focused laser beam they use two unfocused beams that are generated towards one another. Forces in the region where the beams overlap will not only trap any cell within it but also deform that cell.
Turning up the power will cause further deformation—or stretching—along the axis of the beams. The more deformable the cell, the more it stretches.
Professor K?s concedes that the very notion of optical stretching is counterintuitive. "In everyday life we are not used to getting pushed around by sunlight," he jokes.
The machine works by passing a stream of cells, one at a time, through the laser beams. Each is trapped and held for just long enough—as little as one thousandth of a second—to allow the stretch to be measured. As few as 50 cells taken with a needle biopsy are sufficient to distinguish healthy from malignant tissue.
The equipment has already proved itself in preclinical testing. "We have a prototype that's simple enough for a technician to use," said Professor K?s. The current cost is around 30 000 (￡20 600; $39 000), but industrial manufacturing—if the inventors can find a major investor—should reduce this figure. Then they hope to do the full scale clinical trials needed to prove the value of the technology.(Geoff Watts)
Speaking this week at a meeting organised in Warwick by the Institute of Physics, Professor Josef K?s of the University of Leipzig described how he and his collaborator, Dr Jochen Guck, have used the technology to develop an exceptionally sensitive test for cancer.
Biologists have long known that as healthy cells undergo transformation into tumour cells their filamentous internal scaffolding or cytoskeleton becomes softer and more yielding. For this reason cancer cells are more easily deformed. Optical stretching offers a way of measuring the deformation that cells undergo when placed within narrow but powerful light beams.
The technique is a variant of what's known as the "optical tweezers." This instrument comprises a focused beam of laser light in which it is possible to trap objects the size of cells and then manipulate them. The optical stretcher invented by Professor K?s and his colleagues is a variant of this device.
Instead of a single focused laser beam they use two unfocused beams that are generated towards one another. Forces in the region where the beams overlap will not only trap any cell within it but also deform that cell.
Turning up the power will cause further deformation—or stretching—along the axis of the beams. The more deformable the cell, the more it stretches.
Professor K?s concedes that the very notion of optical stretching is counterintuitive. "In everyday life we are not used to getting pushed around by sunlight," he jokes.
The machine works by passing a stream of cells, one at a time, through the laser beams. Each is trapped and held for just long enough—as little as one thousandth of a second—to allow the stretch to be measured. As few as 50 cells taken with a needle biopsy are sufficient to distinguish healthy from malignant tissue.
The equipment has already proved itself in preclinical testing. "We have a prototype that's simple enough for a technician to use," said Professor K?s. The current cost is around 30 000 (￡20 600; $39 000), but industrial manufacturing—if the inventors can find a major investor—should reduce this figure. Then they hope to do the full scale clinical trials needed to prove the value of the technology.(Geoff Watts)