Pathological consequence of misguided dendritic cell differentiation in histiocytic diseases.
Histiocytic disorders represent a group of complex pathologies characterized by the accumulation of histiocytes, an old term for tissue-resident macrophages and dendritic cells. Langerhans cell histiocytosis is the most frequent of histiocytosis in humans and has been thought to arise from the abnormal accumulation of epidermal dendritic cells called Langerhans cells. In this chapter, we discuss the origin and differentiation of Langerhans cells and dendritic cells and present accumulated evidence that suggests that Langerhans cell histiocytosis does not result from abnormal Langerhans cell homeostasis but rather is a consequence of misguided differentiation programs of myeloid dendritic cell precursors. We propose reclassification of Langerhans cell histiocytosis, juvenile xanthogranuloma, and Erdheim-Chester disease as inflammatory myeloid neoplasias.
Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, USA; Tisch Cancer Institute; Immunology Institute.
Marie-Luise
ML
Berres
Carl E
CE
Allen
Miriam
M
Merad
D000818:Animals; D002454:Cell Differentiation; D003713:Dendritic Cells / Q000473:pathology*; D015614:Histiocytosis / Q000276:immunology / Q000473:pathology*; D006801:Humans
BRAFV600E; DC differentiation; Dendritic cell lineage; Erdheim–Chester disease; Histiocytic disorders; Juvenile xanthogranuloma; Langerhans cell histiocytosis; Macrophages