Macrophages, dendritic cells and histiocytic disorders

Résumé fourni par la source

The myeloid mononuclear cells, monocytes, macrophages and dendritic cells (DC) are among the most varied and elusive members of the haematopoietic family. Macrophages, one of the earliest defence systems in evolution, inhabit almost all human tissues. Recent evidence shows that many are created in prenatal life and persist independently of the bone marrow in adulthood. DC are a more recent phylogenetic addition that many decades of research have finally disentangled from their close but distinct relative, the monocyte. Monocytes and DC are deficient in a new class of immunodeficiency caused by mutation of GATA2 , IRF8 and other genes. In the histiocytic neoplasms, Langerhans cell histiocytosis, Erdheim Chester disease and juvenile xanthogranuloma, myeloid cells are transformed by mutation of the MAP kinase pathway, a discovery that has far-reaching implications for patients with these rare but potentially lethal disorders. Overdosing on cytokines creates a storm of macrophage-mediated inflammation in haemophagocytic lymphohistiocytosis (HLH). A greater recognition of this syndrome and use of new biologics to treat it hold great promise for improving outcomes.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.