Updated project metadata. Niemann-Pick type C disease is a rare neurodegenerative disorder mainly caused by mutations in Npc1, resulting in abnormal late endosomal/lysosomal lipid storage. Although microgliosis is a prominent pathological feature, direct consequences of NPC1 loss on microglial function remain uncharacterized. Previously, we have characterized microglial proteome alterations in the NPC1 KO mouse model (PXD019447). In order to investigate similar changes in humans, we have cultured monocyte derived macrophages of NPC1 patients and control donors.