TEM micrographs of sectioned control- (A-B), and di-h-HALI treated LSECs (C-D). (A) Sectioning through the nuclear region (N) reveals a complex sponge-like appearance of fenestrae lying around the nucleus (arrow). Notice the presence of vacuoles (arrowheads). Scale bar, 1 μm. (B) Section through the peripheral cytoplasm reveals fenestrae grouped in sieve plates (large arrow). Note the difference between fenestrae (small arrow), endocytotic vesicles (large arrowhead), and vacuoles (small arrowhead). Scale bar, 1 μm. (C) High magnification image of a FFC (large arrow) after 60 minutes of di-h-HALI treatment, showing small fenestrae (small arrowheads), which form rows of fenestrae with increasing size (large arrowheads). Notice filamentous structures (asterisks). Scale bar, 200 nm. (D) FFC (large arrow) after 120 minutes of di-h-HALI treatment. Notice the granular pattern of the FFC and the absence of connected fenestrae rows at this stage. Fenestrae (small arrow); filaments (asterisks). Scale bar, 200 nm.