The Overgrowth of the Connective Tissue Cells in Infected Wounds.

Abstract

In a previous paper 1 the author has shown that clean skin wounds close in large part by a moving forward of the epithelial cells of the epidermis. These cells drag the uninjured skin of the border of the wound across the opening to cover it. This movement takes place early and quickly before there is any extensive growth of the connective tissue cells. Such movement leads to the most perfect restoration of the wounded area. The growing connective tissue cells inhibit this movement of the epidermis.

In infected wounds the picture changes; the connective tissue cells grow in excess of the epidermal cells. The question arose whether these connective tissue cells are more resistant to bacteria than the epidermal cells. A careful study of many infected cultures of mesenchyme, connective tissue cells and epithelial cells has shown that this is not true. The only cells which invade areas of the medium infected with bacteria are the lymphocytes and leucocytes. They appear to be little disturbed by the growing bacteria. All fixed tissue cells are strongly inhibited by all of the growing bacterial cells, so far tested.

Having established this fact, it became evident that other peculiarities of the connective tissue cells or the connective tissue of the skin must allow them to show activity in the presence of bacteria where the epithelial layer cannot become active. In studying the difference between the epithelial and connective tissue cells (fibroblasts) in the tissue culture the author has noted 2 that the connective tissue cells transform the fibrinogen of the exudate of the wound into true fibrin.