Abstract
Abstract: :
Purpose: Mechanical wounding of epithelial cell sheets is a commonly used model to study wound healing in vitro. Generally, significant cell damage is seen at the wound edge, and wounds heal by migration of cells into the denuded area. Cell damage has been suggested to be instrumental for the healing response, and the purpose of these studies was to evaluate the importance of this for healing of wounds in cultures of corneal epithelial cells. Methods: Denuded areas of secondary cultures of rabbit epithelial cells were introduced by wounding with a pipette tip or by removal of blocks of ParafilmTM or agarose. The widths of the wound were followed over time. Activation of JNK kinase was followed with a phospho-specific antibody, and permeability of cells by uptake of fluorescent dyes. Results: Mechanical wounding of cell layers resulted in extensive cell damage and activation of the JNK kinase, whereas these effects were greatly reduced by introduction of a denuded area by removal of a physical block. However, in both cases, extensive production of lamellipodia at the wound edge was observed, and closure of wounds proceeded at similar rates. Conclusions: The extensive cell damage seen in response to mechanical wounding is not a prerequisite for healing of wounds in corneal epithelial cell sheets in vitro. It is of great interest to define the factors that triggers the healing response.
Keywords: cornea: epithelium • cell-cell communication • wound healing