title: Evaluation of serum KL-6 levels in patients with pulmonary tuberculosis.
abstract: METHODS
  KL-6, a human MUC-1 mucin preferentially expressed on type II pneumocytes, is a sensitive serum marker for evaluating alveolar damage of interstitial pneumonia and pulmonary fibrosis. Some patients with pulmonary tuberculosis develop severe respiratory dysfunction caused by extensive pulmonary fibrosis, compensatory emphysema and fibrous pleural thickening.
  
  
  OBJECTIVE
  To evaluate the clinico-pathological significance of KL-6 in pulmonary tuberculosis.
  
  
  METHODS
  Serum KL-6 levels were measured in sera from 57 patients with active pulmonary tuberculosis and 38 healthy controls by a sandwich-type enzyme-linked immunosorbent assay. Immunohistochemistry was performed by an avidin-biotin-peroxidase complex method.
  
  
  RESULTS
  KL-6 levels were significantly higher in the patients than in the healthy controls (518 +/- 693 [SD] vs 227 +/- 91 U/ml, P < 0.001) and increased significantly according to the extent of pulmonary lesions evaluated by chest X-ray (P < 0.001). There was a significant negative correlation between serum KL-6 levels and % vital capacity (VC) (r = 0.642, P < 0.05). KL-6 was strongly expressed on proliferated type II pneumocytes and cuboidal epithelial cells adjacent to thickened intralobular septa and pleura.
  
  
  CONCLUSIONS
  In pulmonary tuberculosis, serum KL-6 originates from proliferated type II pneumocytes and cuboidal epithelial cells, and is a useful marker presenting the degree and extent of pulmonary fibroproductive lesions.
authors.affiliation: Second Department of Internal Medicine, Ehime University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Inoue
authors.forename: K
authors.initials: K
authors.lastname: Nishimura
authors.forename: M
authors.initials: M
authors.lastname: Shiode
authors.forename: H
authors.initials: H
authors.lastname: Akutsu
authors.forename: H
authors.initials: H
authors.lastname: Hamada
authors.forename: S
authors.initials: S
authors.lastname: Fujioka
authors.forename: S
authors.initials: S
authors.lastname: Fujino
authors.forename: A
authors.initials: A
authors.lastname: Yokoyama
authors.forename: N
authors.initials: N
authors.lastname: Kohno
authors.forename: K
authors.initials: K
authors.lastname: Hiwada
mesh_terms: D000368:Aged; D000941:Antigens / Q000097:blood*; D000951:Antigens, Neoplasm; D015415:Biomarkers / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D007150:Immunohistochemistry; D008168:Lung / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D018396:Mucin-1; D009077:Mucins; D014397:Tuberculosis, Pulmonary / Q000097:blood*
chemical_list: D000941:Antigens; D000951:Antigens, Neoplasm; D015415:Biomarkers; D006023:Glycoproteins; C060192:MUC1 protein, human; D018396:Mucin-1; D009077:Mucins