[Process formation and dynamics of the spreading of cultured cells on an extracellular matrix of fibroblasts].

Flattening of the normal mouse and human fibroblasts and of the epithelial cells (lines from rat liver IAR-2, trachea of calf foetus FBT and mouse kidney MPTR) was studied on isolated extracellular matrix (EM) formed by human fibroblasts in culture has been studied. EM consisted of fibers, usually parallel to each other. Flattening of the fibroblasts on EM was slower and less even than on glass. Separate processes formed in place of a ring lamella and those processes gradually stretched which were parallel to the EM fibers. Within 24 h fibroblasts were stretched and oriented along the EM fibers. At the EM-glass boundary fibroblasts migrated from EM to glass. Epithelial cells also flattened on EM more slowly and unequally on EM than on glass. Within 24 h, the IAR-2 and FBT cells were less flattened than on glass, acquired a disc-like shape with uneven contours and, sometimes, an oval shape. MPTR cells and their colonies were oriented and stretched along the EM fibers.