Figure 2. MPO levels in leukocytes retrieved from blood and transplants.

(A) Flow cytometric intracellular MPO staining on lymphocytes, neutrophils, Ly-6C^hi monocytes, and Ly-6C^lo monocytes. 1 of 3 representative experiments is shown. Numbers indicate percentage of cells in respective gates. (B) Relative contribution of leukocytes to overall MPO expression in allografts and isografts. The area of the pie chart reflects overall MPO content per mg tissue, which is the product of per cell MPO content and the abundance of each cell type in the heart, as determined by flow cytometry. (C) MPO activity (n = 3) of lysed sorted leukocytes.