Localization of LIGHT in thrombus material. Photomicrographs showing immunostaining and localization of LIGHT in thrombus material removed from the site of plaque rupture in patients with STEMI undergoing PCI. Thrombus material stained with omission of the primary antibody served as control and demonstrated no immunostaining of any of the cellular elements (A). Fairly strong immunostaining of LIGHT (B) was seen in areas with platelets (*) and in monocytes/macrophages (arrows). Panel C demonstrates thrombus material with CD41⁺platelets, and panel D demonstrates calprotectin-positive monocytes/macrophages. Original magnification ×400.