FIGURE 4.

Electron microscopy and high-resolution light microscopy examination of SM accumulation and clearance from Kupffer cells. A, The characteristic “fingerprint” whorls of SM present in Kupffer cells at baseline in patient 3. Electron dense lipofuscin (L) is also present. Insets in A: Kupffer cell SM is dark purple in modified toluidene blue sections (left) and red in lysenin affinity sections (right). B, The clearance of SM, with lipofuscin remaining (L). Insets in B: This residual lipofuscin appears light blue in modified toluidene blue sections (left) and blue-green in lysenin affinity sections (right). Electron microscopy scale bars=1 μm.