Fascicular nerve allograft evaluation. Part 1: comparison with autografts by light microscopy.

In a comparative experiment, transplantation of orthotopic nerve fascicle was performed on 100 sciatic nerves between inbred, antigenically identified rats. The authors studied cellular response, macrophage reaction, connective-tissue reaction, myelination, and distal/proximal axonal ratios, but no difference could be established between allografted and autografted fascicles after 2 months. Moreover, there was no evidence of any graded rejection phenomenon dependent on differences of tissue typing. Theories for the decreased antigenic reaction of nerve fascicles are proposed.