Figure 2.

Ultrastructural characteristics used to identify the different fibrocyte types. (A) Type I cells are elongated with thin, organelle-poor cytoplasm (cy) and a few fine processes (arrow). (B) Type II cells have dense cytoplasm (cy) containing many organelles and numerous fine processes (arrow). (C) Type III cells are variably shaped, often flattened, with dense, narrow cytoplasm and string-like processes. (D) Type IV cells are also variably rounded or elongated, with a number of fine processes, and thin cytoplasm. Type V cells strongly resemble type II cells, with the cytoplasm (cy) containing many organelles and multiple fine processes (arrow). Scale bars: A and C = 5 µm; B, D, and E = 2 µm.