Background: The cytoskeleton of cells in blood vessel walls contains desmin, vimentin, and cytokeratins. The distribution of these proteins in human vessels is not fully known, We have mapped the distribution of intermediate filament proteins in human arterial walls. Methods: Monoclonal antibodies targeted at the intermediate filament proteins desmin, vimentin, and cytokeratins were used, and the distribution of these proteins was studied by immunohistochemistry. Results: In the muscular arteries, most smooth muscle cells in the media expressed both desmin and vimentin; in the elastic arteries, the proportion of desmin-labelled cells was lower and preferentially located to the periphery of the media, In general, the desmin immunoreactivity within the intima was weak, but some smooth muscle cells and smooth muscle cells in the musculoelastic layer showed strong immunoreactivity. The vasa vasorum exhibited a heterogeneous desmin-labelling pattern, The vimentin antibodies labelled the endothelium and showed a heterogeneous staining pattern in the other layers of the arterial wall, Cytokeratin was detected in occasional cells in the media of muscular arteries, in many adluminal cells and cell clusters in the coronary intima, and in smooth muscle cells in the media of the elastic arteries. Conclusions: Vimentin is widely distributed in vascular smooth muscle cells, whereas the distribution of desmin and cytokeratin varies. Each artery studied had an intermediate filament pattern typical for the anatomical location, There were no interindividual variations in the distribution of intermediate filament proteins. (C) 1997 Wiley-Liss, Inc.
