THE HUMAN CUTANEOUS BASEMENT MEMBRANE-ANCHORING FIBRIL COMPLEX: PREPARATION AND ULTRASTRUCTURE

The human cutaneous basement membrane (CBM) has been isolated together with the anchoring fibrils (AF) of the dermis. These structures are removed from the dermis as a single complex, the CBM-AF complex. The epidermis is first removed from the dermis by immersion of whole, defatted skin in cold 2 N NaSCN for 5 to 6 hr. Subsequently, removal of the CBM-AF complex is effected by focusing high-intensity ultrasonic energy against the dermal surface. Purification of the preparation is achieved by low-speed sedimentation. All stages of the process were monitored by electron microscopy, which demonstrated that the morphology of the CBM-AF complex was well preserved and that this complex represents the principal mass component in the system. In addition, our report describes an ultrasound-induced variation in collagen fibril morphology, which we have called “disordered collagen.” This altered type of fibril lacks periodicity or recognizable banding and has a frayed appearance. Finally, the experiments provide the basis for an analysis of the relative strengths of certain bonds at the dermal—epidermal junction. The strongest of these appears to be the bond between basement membrane and anchoring fibril