Xanthoma tissue-extracted LDL density substances are the main inducer of myelin-like bodies and ceroid granules in foam cells.
Characteristic intracellular organelles of the foam cells in xanthoma are composed of membrane-bound lipid vacuoles, membrane-free lipid vacuoles, cholesterol crystals, multivesicular or multilocular lipid bodies, myelin-like bodies, and ceroid granules. We aimed to clarify the formation of myelin-like bodies and ceroid granules in the foam cells of xanthoma. We ultrastructurally examined mouse peritoneal macrophages incubated with human low-density lipoprotein (LDL) modified by incubation with xanthoma tissue, with xanthoma tissue-extracted LDL density substances, and with homogenized xanthoma tissue-derived crude material. A large number of membrane-bound and membrane-free lipid vacuoles were observed in macrophages incubated with xanthoma tissue-modified LDL. The macrophages incubated with the xanthoma tissue-extracted LDL density substances contained a large number of myelin-like bodies and ceroid granules. The macrophages incubated with the homogenized xanthoma tissue-derived crude material accumulated many vacuoles containing vesicular structures and a small number of myelin bodies and ceroid granules. Membrane-bound lipid vacuoles are derived from lysosomes that accumulate mostly extravasated modified LDL in xanthoma tissue. On the other hand, myelin-like bodies and ceroid granules are mostly derived from LDL density substances derived from xanthoma tissue homogenate.
Nakajima
Kimiko
K
Department of Dermatology, Kochi Medical School, Okohcho, Nankoku, Kochi 783-8505, Japan. nakajimk@kochi-u.ac.jp
Ikeda
Mitsunori
M
Yagyu
Ken-Ichi
K
Nakajima
Hideki
H
Matsumoto
Masaaki
M
Seike
Masahiro
M
Kodama
Hajime
H
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D002566:Ceroid / Q000378:metabolism*; D005487:Foam Cells / Q000378:metabolism / Q000648:ultrastructure*; D006801:Humans; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008247:Lysosomes / Q000378:metabolism / Q000648:ultrastructure; D017737:Macrophages, Peritoneal / Q000378:metabolism / Q000648:ultrastructure*; D051379:Mice; D046529:Microscopy, Electron, Transmission; D009186:Myelin Sheath / Q000378:metabolism* / Q000648:ultrastructure; D011817:Rabbits; D014617:Vacuoles / Q000378:metabolism / Q000648:ultrastructure; D014973:Xanthomatosis / Q000378:metabolism* / Q000473:pathology
D002566:Ceroid; D008077:Lipoproteins, LDL