title: The ultrastructure of a membranous structure, the labyrinth, present in bone marrow plasma cells.
abstract: The ultrastructure of a complex membranous structure, the labyrinth, is described. This structure was found in bone marrow plasma cells from patients with multiple myeloma as well as from other groups of patients. It is concluded that the labyrinth may represent a rare route of secretion by which plasma cells are able to excrete waste products and simultaneously secrete intracellularly synthesized material.
mesh_terms: D001853:Bone Marrow / Q000648:ultrastructure; D001854:Bone Marrow Cells; D006801:Humans; D007425:Intracellular Membranes / Q000648:ultrastructure*; D008854:Microscopy, Electron; D009101:Multiple Myeloma / Q000648:ultrastructure*; D009940:Organoids / Q000648:ultrastructure; D010950:Plasma Cells / Q000378:metabolism / Q000648:ultrastructure*