ABSTRACT
A comparison of the adhesion of human primary keratinocytes to laminin-1 from murine EHS sarcoma and laminin-2/4 from human placenta was carried out using two methods, cell adhesion to substrates covered with the laminin isoforms, and interaction of keratinocytes from suspension with latex beads coated with the proteins. Laminin-2/4 was considerably more potent as a promoter of attachment of primary human keratinocytes than laminin-1 (and fibronectin), with increased attachment of cells correlating well with the number of latex bead binding sites. Only small cells of diameter of less than 20 microm bound more than 5 beads. Staining of keratinocytes with involucrin antibodies confirmed the existence of an inverse relationship between laminin-2/4-coated bead binding and differentiation.
Subject(s)
Keratinocytes/cytology , Laminin/pharmacology , Animals , Cell Adhesion/drug effects , Cells, Cultured , Fibronectins/pharmacology , Humans , Mice , Microspheres , Placenta/chemistry , Sarcoma/chemistry , Skin/cytology , Soft Tissue Neoplasms/chemistry , Wound Healing/physiologyABSTRACT
The influence of matrigel, a mixture of the components of thebasement membrane, on the wound healing was studied in a modelof experimental wounds in rats. Matrigel was found to increasethe rate of epithelization of split-thickness wounds. The modelof deep wound was developed in which the host animal could notprovide enough migrating and proliferating keratinocytes tocover the wound area. The model is relevant to severe burns andinjuries in humans. When rat keratinocyte suspension wastransplanted into deep wounds, cell retention in the wound bedwas only observed if matrigel was added together with the cells.Increasing matrigel concentration in the wound was seen toenhance the rate of wound area coverage by the cells. Althoughthe process of healing seemed macroscopically normal, afterhistological screening of the biopsies cell in the wouldappeared as amorphous aggregates and tubules rather thenstratified epidermis.
ABSTRACT
We studied the effect of feeder cells (fibroblasts) and a mixture of the extracellular matrix components, Matrigel, on spreading and cytoskeleton organization of newborn rat keratinocytes (REK). REK formed lamellipodia on being plated together with feeder cells and on the Matrigel as a substrate whereas the same REK plated alone on a plastic surface formed filopodia. REK lamellipodia formation in co-cultures depended on the fibroblast addition time. Although conditioned medium from fibroblast cultures was not enough to induce lamellipodia, the extracellular matrix left after fibroblast removal was as effective as Matrigel. Our results indicate that lamellipodia formation seems to depend on the factor(s) secreted by fibroblasts and associated with the extracellular matrix.
