Somatic unmyelinated fibre degeneration in rabbits with granulomatous hypersensitivity produced by a non-myelin antigen in sensory peripheral nerve.

Rabbits previously sensitised by injection of human sensory peripheral nerve showed degeneration of somatic unmyelinated fibres at skin test sites when challenged by sensory nerve or certain non-myelin fractions prepared from human sensory nerve. Epithelioid cells were found in the endoneurium and may mediate the nerve damage. The degeneration was consistently found and lasted for at least 58 days. Phagocytosing macrophages were absent. Differences in the pattern of nerve damage to that of EAN and EAE are discussed.