Localization of caveolin 1 in aortic valve endothelial cells using antigen retrieval

Ultrastructural analysis of aortic valve endothelial cells subjected to growth arrest revealed many vesicles defined as caveolae by the localization of caveolin. Translocation of caveolin after exposure to oxidized LDL suggests that the localization of caveolin may be a valuable tool to study models of early atherogenesis. In this study, several antigen retrieval protocols were tested in osmium-fixed and Spurr-embedded cells to determine the optimal method of antigen retrieval in our model system. SDS produced the most consistent labeling pattern. A quantitative evaluation revealed that SDS significantly increased the labeling density in Spurr-embedded cells. The labeling pattern appeared as clusters of gold particles, 15-40 nm in diameter, that were associated with membranes of a gold labeling similar size which may represent the neck region of the caveolae.