The role of large extracellular matrix glycoproteins in regenerating laser-treated tissue

Abstract

The distribution of large extracellular matrix glycoproteins tenascin, cellular fibronectin and laminin was studied in healing CO 2 laser, scalpel incision and excision wounds of rat tongue dorsal mucosa in 153 rats over a period of 42 days by indirect immunofluorescence microscopy using mono- and polyclonal antibodies. A local increase in tenascin distribution in the basement membrane zone indicated that this protein was important to epithelial cell proliferation and movement. The increased amount of cellular fibronectin in the provisional stromal matrix showed that this protein was a crucial component in healing wounds. An increased expression of laminin in the basement membranes of the wound borders, blood vessel walls and nerve structures suggested that this protein could guide and stimulate the regenerating epithelial cells. In laser wounds, re-epithelialization seemed to progress upon the laminin-containing structures, although the formation and subsidation of laminin back to normal seemed to be somewhat slower. The results show that long observation times are needed when studying laser wound healing.