Birbeck granules

Birbeck granules, also known as Birbeck bodies, are rod shaped or "tennis-racket" cytoplasmic organelles with a central linear density and a striated appearance. First described in 1961, they are solely found in Langerhans cells. Although part of normal Langerhans cell histology, they also provide a mechanism to differentiate Langerhans cell histiocytoses from proliferative disorders caused by other cell lines.

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