MORPHOLOGIC QUANTIFICATION OF BLOOD-PLATELETS BY IMAGE-ANALYSIS

OBJECTIVE: For morphologic and functional investigations on the physio logy and pathology of human blood platelets, their adhesion plays an i mportant role. This feature is normally assessed concerning qualitativ e aspects, but there is a lack of quantitative investigations. STUDY D ESIGN: We developed a model to quantify in vitro manipulations on thro mbocytes by measuring their adhesion areas automatically. This was ach ieved by combining the VIDAS 2.5 image analysis system with reflection contrast microscopy (RCM). The evaluation was performed independent o f the position of the grey value histogram by analyzing each digitized image correspon?ding to its individual mean grey value. RESULTS: The applicability and validity were verified from the example of a pharmac ologic experiment administering the platelet stimulant oxidized low de nsity lipoprotein (ox-LDL) to thrombocyte suspensions and confirming i t by aggregometry. We assessed the temporal increase in adhesion area and mean total adhesion area of activated platelets, comparing unstimu lated to stimulated ones. Ox-LDL accelerated the adhesion process and increased tire adhesion area. CONCLUSION: The combination of RCM with consecutive image analysis provides useful parameters for in vitro exa mination on vital human platelets. Large amounts of data can be accumu lated in a short time for an evaluation of influences of and on blood platelets.