A NEW APPROACH TO ASSESS VIABILITY OF ADULT CARDIOMYOCYTES - COMPUTER-ASSISTED IMAGE-ANALYSIS

Objective: to develop a computerized procedure to obtain the percentag e of rod-shaped cells in preparations of isolated adult cardiomyocytes . Methods: (1) isolated adult rat myocytes were either pretreated with a fixative (0.2% glutaraldehyde, 0.25% Triton X-100 and 0.1% trypan b lue) or monitored via phase-contrast optics without fixation; (2) an i mage field with several hundred cells was captured by a microscope-mou nted video camera, which was connected to a frame grabber, and saved a s a TIFF file: (3) the image was processed using Mocha software. Analy sis consisted of setting the image threshold, an object count, automat ic measurements of objects and their classification. Results: though t he software could measure many geometrical characteristics, a combinat ion of two parameters, object size and shape factor, was found to be t he most efficient. With these parameters, four classes of sample objec ts were constructed including rod-shaped myocytes, round damaged cells , overlapping cell clusters, and small debris. Test objects were class ified automatically based on which sample object their parameters matc hed the most, Excellent correlation was obtained between manual counts and computer analysis of cell viability (r = 0.98). Conclusion: a mor e efficient method, based on computer-assisted classification of objec ts, has been developed to assess the viability of isolated adult cardi omyocytes. (C) 1998 Academic Press Limited.