Size control of decorin dermatan sulfate during remodeling of collagen fibrils in healing skin.

Recently it has been reported that the molecular size of decorin dermatan sulfate (DS) was increased in healing skin after hapten application and that the elongated DS was distributed in enlarged interfibrillar space among thin collagen fibrils in situ. Here we show that such modulation of the length of decorin DS is temporary. Although the size of decorin DS was evidently increased on day 15, it decreased to almost normal size on day 35 when the altered disaccharide composition of DS was also recovered. Electron microscopic observation revealed that elongated decorin DS was localized among thin collagen fibrils packed loosely in hapten-treated skin on day 15. In contrast, decorin DS of normal size was distributed among thick collagen fibrils packed tightly on day 35. These results suggest that size control of decorin DS plays important roles in organization of collagen fibrils into bundles by regulating interfibrillar space in healing skin, particularly in maturation of collagen fibrils through shortening of decorin DS in later stages of healing.