Fig. 8.

The myelinated nerves of mouse brain from the test group at 132 days post challenge. Upward arrows indicate that the myelin sheath had collapsed and spread to the cytoplasm and the infolded myelin sheath had further developed into phagocytic vacuoles and rightward arrows indicate that multi-membrane vacuoles had formed in some myelin sheaths and the aggregated black particles were dissolving in these vacuoles