FIG. 12.

TEM image showing a fibripositor-like structure in a 1% FBS + 1% ITS culture sample that was prepared via QFDE. Remaining portions of the cell membrane in the fractured replica are indicated; “F” indicates the plane of fracture across the cell membrane. A fibripositor-like pore of approximately 530-nm-diameter is indicated by the arrow, with a tight bundle of fibrils extruding through the pore. Each fibril is approximately 30–40 nm in diameter. The bundle appears to be covered in a ground substance. Scale bar is 500 nm.