A new model for studying the effects of Mycobacterium leprae on Schwann cell and neuron interactions,” The

Millions of patients with leprosy suffer from nerve damage resulting in disabilities as a consequence of Mycobacterium leprae infection. However, mechanisms of nerve damage have not been elucidated because of the lack of a model that maintains M. leprae viability and mimics disease conditions. A model was developed using viable M. leprae, rat Schwann cells, and Schwann cell–neuron cocultures incubated at 33C. M. leprae retained 56 % viability in Schwann cells for 3 weeks after infection at 33C, compared with 3.6 % viability at 37C. Infected Schwann cells had altered morphology and expression of genes encoding cellular adhesion molecules at 33C but were capable of interacting with and myelinating neurons. Cocultures, infected after myelination occurred, showed no morphological changes in myelin architecture after 1 month of incubation at 33C, and M. leprae retained 53 % viability. This article describes a new model for studying the effects of M. leprae on Schwann cells. Mycobacterium leprae is an obligate intracellular parasite that is unique among bacterial pathogens in its ability to invade the peripheral nervous system and is the leading cause of non-traumatic neuropathy worldwide. Approximately 3 million pa