ULTRASONIC BIOMICROSCOPY OF VIABLE, DEAD AND APOPTOTIC CELLS

Ultrasonic imaging is frequently used in medical diagnosis to differen tiate normal and tumour tissues, Here we investigate if distinct types of cell death can be discriminated through the use of ultrasound biom icroscopy. By using a well-controlled system in vitro, we demonstrate that this imaging modality can be used to differentiate living cells, dead cells and cells that have died by programmed cell death or apopto sis, The results indicate a greater than twofold ultrasound backscatte r signal from apoptotic cells in comparison to viable cells, whereas h eat-killed cells exhibit an intermediate level of ultrasound backscatt er, The results have potential implications in the study of disease-re lated biological processes involving apoptosis. (C) 1997 World Federat ion for Ultrasound in Medicine & Biology.