Organized nerve culture. I. A technique to study the effect of M. leprae infection.

Neonatal dorsal root ganglia were cultivated in vitro by the technique of Murray. Within a week bundles of organized nerve fibers containing proliferating Schwann cells in different phases of axon association and fibroblast cells destined to become peri- or endoneural cells were obtained, peri- or endoneural cells were obtained. Many of these nerve fibers were myelinated within 3-4 weeks. Such 1 or 2 week old cultures were inoculated with M. leprae, and bacilli were found in the cytoplasm of Schwann cells and fibroblasts, demonstrating that these cells are phagocytic in nature and that it is possible to infect them with M. leprae, Schwann cells, mostly in the free or early association phase, engulfed the bacilli, and this affected their further interaction with the axons and subsequent myelin synthesis.