Figure 1.

Immunohistochemical localization of MrgD receptors (MrgD R) clearly shows positive immunostaining within atherosclerotic plaques and the endothelial layer. The first row shows 3-μm serially adjacent sections stained for RAM-11 (Macrophage), MrgD R and HHF-35 (smooth muscle cells). Inserted cropped sections show little or no staining for macrophage/MrgD R +/+ cells (arrows), yet HHF-35/MrgD R +/+ cells were abundant (cropped sections in 2nd row attached by dashed line as well as identified by letters A, B and C). In other plaques, cells expressing eNOS also expressed MrgD R (3rd row, letters D, E and F), and the endothelial layer also showed co-expression of both proteins (cropped sections, 3rd row). Small arterioles in the vaso vasorum showed positive endothelial MrgD R (cropped sections, 4th row), and negative controls also shown (−). All sections were photographed at an original 400× magnification.