SPECIFIC ADHESION MOLECULES BIND ANCHORING FILAMENTS AND ENDOTHELIAL CELLS IN HUMAN SKIN INITIAL LYMPHATICS

Abstract

Anchoring filaments are a characteristic feature of initial lymphatic vessels. They connectthe abluminal membrane of endothelial cells to the surrounding elastic fibers. The mainmolecular component of anchoring filaments is fibrillin. Initial lymphatic vessels of human skinwere stained with monoclonal antibodies to fibrillin, integrins "2$1, "3$1 and "v$3, vinculin,talin, $-actin and focal adhesion kinase (FAK). A double-labeling immunofluorescence methodwas used to simultaneously stain fibrillin and "v$3 integrin or FAK. Close contiguities betweenintegrins and anchoring filaments were observed. These results suggest that the anchoringfilaments connect the extracellular matrix and the endothelial cell cytoskeleton through thetransmembrane integrin and FAK molecule. The results also demonstrate the presence of focaladhesions in the wall of initial lymphatic vessels. These connections possibly enable transmissionof chemical and/or mechanical stimuli from the extracellular matrix to the endothelial cells.Here, they are transformed in cytoskeleton rearrangements and intracellular signaling events,some of which may contribute to the initial formation of lymph.