Transmission electron micrograph of the skin biopsy. Normal keratinocytes form the roof of the split (S) and the dermis is at its base. Desmosomes (D) are still visible whereas hemidesmosomes are not present. The lamina densa (LD) is located at the base of the split. Normal collagen fibers (CF) are visible in the superficial dermis. TEM. 2,800x.