Network of vascular-associated dendritic cells in intima of healthy young individuals

In earlier studies, our group has established a new "immunological" hypothe sis for atherogenesis supported by experimental and clinical studies showin g that inflammatory immunological reactions against heat shock protein 60 i nitiate the development of atherosclerosis. In the present study, we descri be the discovery of a so-far-unknown network of dendritic cells in the inne rmost layer of arteries, the intima, but not veins of healthy humans and ra bbits. The number of these dendritic cells is comparable to that of Langerh ans cells in the skin, and dendritic cells show a similar phenotype (CD1aS-100(+) lag(+) CD31(-) CD83(-) CD86(-) and no staining for von Willebrand factor or smooth muscle cell myosin). These vascular-associated dendritic c ells accumulate most densely in those arterial regions that are subjected t o major hemodynamic stress by turbulent flow conditions and are known to be predisposed for the later development of atherosclerosis. These results op en new perspectives for the activation of the immune system within the arte rial wall.