Lymphatic microvessels in intima of abdominal aortic aneurysm.

<p>EVG staining of normal aorta (<b>A</b>) and abdominal aortic aneurysm (AAA) wall (<b>B</b>). Immunohistochemistry for podoplanin corresponding to the areas outlined with a solid line in <b>A</b> and <b>B</b> (<b>C</b>, normal aorta; <b>D</b>, AAA). Podoplanin-positive microvessels were markedly increased in the intima in AAA wall. <b>E</b>, Higher magnification of the outlined area in <b>D</b>. Double immunofluorescence staining of lymphatic vessels in intima of AAA (<b>F</b>–<b>I</b>). <b>F</b>, Podoplanin (red); <b>G</b>, Prox-1 (green); <b>H</b>, DAPI (blue); <b>I</b>, merge of podoplanin, Prox-1, and DAPI. Double immunofluorescence staining of smooth muscle cells in intima of AAA (<b>J–M</b>). <b>J</b>, podoplanin (red); <b>K</b>, alpha smooth muscle isoform of actin (green), <b>L</b>, DAPI (blue); <b>M</b>, merge of podoplanin, alpha smooth muscle isoform of actin, and DAPI. Immunohistochemistry for podoplanin corresponding to the areas outlined with a dotted line in <b>A</b> and <b>B</b> (<b>N</b>; normal aorta, <b>O</b>; AAA). Lymphatic vasa vasorum was observed in adventitia in both normal aorta (<b>N</b>) and AAA (<b>O</b>) (black arrow: LVV). Scale bars indicate 100 µm (<b>A, B</b>), 50 µm (<b>C, D, J–M, N, O</b>), and 10 µm (<b>E–I</b>). Lymphatic microvessel density; the mean number of lymphatic microvessel (LMVs) in 10 microscopic fields at high magnification (×200) (<b>P</b>). Percentage of lymphatic microvessel area in 10 microscopic fields at high magnification (×200) (<b>Q</b>). Lymphatic microvessel density and percentage of lymphatic microvessel area were compared between normal aorta and AAA. (*<i>P</i><0.001).