title: Ultrastructural studies on the formation and distribution of lipid droplets in the lung capillary endothelial cells in patients with sarcoidosis.
abstract: OBJECTIVE
  We previously reported the presence of definite morphological alterations in the capillary endothelium of sarcoid lung. The aim of this study was to examine ultrastructural changes and distribution of lipid droplets in the endothelium of lung capillaries of patients with sarcoidosis.
  
  
  METHODS
  Tissue specimens were obtained by transbronchial lung biopsy or open lung biopsy from 16 patients with sarcoidosis and 13 controls. Biopsies were evaluated by electron microscopy following lead citrate and uranyl acetate staining.
  
  
  RESULTS
  Typical lipid droplets were observed in pulmonary capillaries of 11 out of 16 sarcoid patients (69%); the droplet frequency was higher in sarcoid patients than in control specimens. Lipid droplets were characterized by biphasic density: most droplets contained eccentrically located vacuoles (saturated fatty acids) others were characterized by low density areas (unsaturated fatty acids). Biphasic droplets were covered by large lysosomal granules and were mainly distributed in the endothelium and pericytes. Interestingly, in the latter, vacuoles increased in size while small amounts of lysosomal granules were detectable.
  
  
  CONCLUSIONS
  Our findings suggest that biphasic droplets increase in number in pulmonary capillaries of patients with sarcoidosis with a characteristic distribution pattern from the endothelium to pericytes.
authors: Department of Internal Medicine, School of Medicine, Shinshu University, Matsumoto, Japan.
authors: I
authors: I
authors: Mochizuki
authors: T
authors: T
authors: Honda
authors: Y
authors: Y
authors: Ookubo
authors: K
authors: K
authors: Kubo
authors: S
authors: S
authors: Koyama
authors: K
authors: K
authors: Hujimoto
authors: S
authors: S
authors: Yoshikawa
authors: S
authors: S
authors: Yamaguchi
authors: S
authors: S
authors: Hayasaka
authors: K
authors: K
authors: Okada
authors: T
authors: T
authors: Hachiya
authors: T
authors: T
authors: Hayano
authors: T
authors: T
authors: Miyahara
authors: T
authors: T
authors: Kobayashi
authors: M
authors: M
authors: Sekiguchi
mesh_terms: D000328:Adult; D002196:Capillaries / Q000378:metabolism / Q000648:ultrastructure; D004730:Endothelium, Vascular / Q000378:metabolism / Q000648:ultrastructure*; D005227:Fatty Acids / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D005260:Female; D006801:Humans; D050356:Lipid Metabolism; D008168:Lung / Q000098:blood supply* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D020286:Pericytes / Q000166:cytology; D017565:Sarcoidosis, Pulmonary / Q000378:metabolism* / Q000473:pathology
chemical_list: D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated