Immunohistochemical detection of intrathrombotic IL-6 and its application to thrombus age estimation

摘要

We immunohistochemically examined intrathrombotic IL-6 expression using a murine model of deep vein thrombosis induced by the ligation of the inferior vena cava (IVC) and discussed the availability of intrathrombotic IL-6 for thrombus age estimation. IL-6(+) cells could be first detected at 1 day after IVC ligation in three of five samples, and all samples with postligation intervals of 3 days or more had intrathrombotic IL-6(+) cells. Thereafter, the numbers of IL-6(+) cells were elevated with the increase of postligation intervals. Double-color immunofluorescence analyses demonstrated that IL-6 was mainly expressed by intrathrombotic macrophages. In all samples with postligation intervals of 5 days or less, the IL-6/macrophage ratio (IL-6/MI center dot) was 0.5 would strongly indicate thrombus ages of a parts per thousand yen7 days. Reciprocally, the ratios of less than 0.5 would suggest thrombus ages of a parts per thousand currency sign5 days. The present study demonstrated that the immunohistochemical detection of IL-6 was suitable to estimate the age of venous thrombi.