01902nas a2200241   4500000000100000008004100001260001300042653001200055653002700067653002200094653001400116653001100130653002100141653002500162653001200187100001600199700001900215245006500234300001100299490000700310520132900317022001401646       2011                            d  c2011 Mar10aAnimals10aDisease Models, Animal10aEpithelioid Cells10aGranuloma10aHumans10aHypersensitivity10aLeprosy, Tuberculoid10aRabbits1 aCrawford CL1 aHardwicke PM D00aExperimental leprosy: a model of epithelioid cell granuloma.  a255-610 v503 a<p>An animal model of granulomatous hypersensitivity has been developed, which reproduces some features of the pathologies of important chronic granulomatous disorders, including tuberculosis, tuberculoid leprosy, sarcoidosis, berylliosis, Crohn's disease, and sensitivity to zirconium. The lesions consist of focal collections of epithelioid cells surrounded by lymphocytes to form tubercles. The epithelioid cell has a secretory function and is not phagocytic. Plasmacytoid dendritic cells are precursors of epithelioid cells, which are therefore part of the innate immune system. Subplasmalemmal linear densities are also present in these cells. This autoimmune model has been induced in rabbits using a non-myelin sensory peripheral antigen to reproduce the features of tuberculoid leprosy. The antigen is probably present only in human tissue. A granuloma antigen, which is tissue specific similar to that in peripheral nerves, could be present in sarcoidosis and Crohn's disease. In multiple sclerosis, mononuclear cells in the brain parenchyma are not phagocytic and are therefore similar to epithelioid cells. The induction of tolerance leading to the development of a vaccine to prevent the lesions in multiple sclerosis, sarcoidosis, and Crohn's disease is possible after purification of the granuloma antigen.</p>  a1365-4632