Immunohistochemical and immunoelectron microscopical analyses of particulate material trapped in the PercuSurge filter.

Red immunoreactivity indicates positive staining in parallel sections. (A) TF in association with distinct cells (arrowheads) and the extracellular compartment (horizontal arrow). The scale bar represents 10 μm. (B) The majority of cells (arrowheads) and extracellular areas (horizontal arrow) stain with anti-CD15 antibody, a marker for mature granulocytes, and monocytes. (C) (D) Documentation of positive staining with anti-CD61 and antifibrin antibodies, which suggests that platelets and fibrin colocalize with TF immunoreactivity. Ultrastructural micrographs of a platelet (insert) and fibrin (insert) obtained from a PercuSurge filter, immunostained with monoclonal anti-TF antibody. The scale bars represent 250 nm. Positive immunoreactivity is visualized with immunogold. Panel C demonstrates the accumulation of TF within platelet granular structures and on the outer membrane (fine arrows). All immunohistochemistry panels were photographed at the original magnification × 400. All immunogold stains were photographed at the original magnification × 28 800.