Circulating microvesicles in mouse blood. (A) Plasma was collected from lactadherin-deficient mice and their littermate controls (N = 3 for each group). The microvesicles were quantified by flow cytometry, based on the light scatter and surface expression of CD42b (n = 3). (B) Wild-type mice were subjected to splenectomy, and the circulating microvesicles were measured 4 hours later. The results are the means and SDs (N = 3).