Fig. 2

Comparaison between AAA and TAA lesions using α-smooth muscle actin (ASMA) immunofluorescence staining. (a) (b) The AAA’s external media, medium media and internal media are more degraded than TAA’s, especially the elastic fibers which auto fluoresce in green. For AAA, the elastic fibers do not have the curvilinear form that they have physiologically. For TAA, the network is interrupted by small afibrillar and acellular areas (white arrows). (c) SMC are stained in red (ASMA) with a blue nuclear (DAPI). They are present in both aneurysms. Their numbers is not significantly different between AAA’s and TAA’s medias or between the three areas of the media (Cb). The total cells number (DAPI+) is not that different between AAA’s and TAA’s medias (Cb). There are more cells in TAA’s adventitia than in AAA’s (p = 0.0498) (Ca). (d) For AAA, atheroma substitutes intima. The SMC are particularly confluent in some areas between internal media and atheroma (Da). They also organize themselves to turn into blood vessels (Db). Atheroma contains cell infiltration (Dc). Their number is more important than the SMC’s (p = 0.0092). *p < 0.1. **p < 0.001. ***p < 0.0001