title: Serum soluble CD26 levels: diagnostic efficiency for atopic dermatitis, cutaneous T-cell lymphoma and psoriasis in combination with serum thymus and activation-regulated chemokine levels.
abstract: BACKGROUND
  CD26 is a multifunctional type II transmembrane glycoprotein, which also exists as a secreted isoform, soluble CD26 (sCD26). The CD26 expression on circulating T cells is decreased in some skin diseases such as cutaneous T-cell lymphoma (CTCL) and psoriasis. It remains to be determined whether sCD26 can be used as a marker of skin diseases or not.
  
  
  OBJECTIVE
  To investigate utility of sCD26 as a diagnostic marker of skin diseases in combination with thymus and activation-regulated chemokine (TARC).
  
  
  METHODS
  Serum sCD26 levels were measured using enzyme-linked immunosorbent assay in 130 participants including 32 patients with atopic dermatitis (AD); 45 patients with CTCL; 26 patients with psoriasis; and 27 healthy controls.
  
  
  RESULTS
  Serum sCD26 levels in patients with CTCL and psoriasis (162.1 ± 80.2 ng/mL and 125.4 ± 82.1 ng/mL respectively) were significantly lower than those of healthy controls (392.6 ± 198.7 ng/mL; P < 0.01 and 0.01 respectively). In patients with CTCL, serum sCD26 levels of patients with advanced stage were 135.0 ± 51.5 ng/mL and they were significantly lower than those with early stage (193.1 ± 96.0 ng/mL; P < 0.05). When we used serum sCD26 and TARC levels for diagnostic criteria, sensitivity, specificity, positive predictive value and negative predictive value for AD, CTCL and psoriasis were 65.2-73.7%, 81.4-97.6%, 65.2-94.4%, and 81.4-88.9% respectively.
  
  
  CONCLUSIONS
  Serum sCD26 levels, combined with serum TARC levels, are helpful in diagnosis of AD, CTCL and psoriasis.
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Miyagaki
authors.forename: M
authors.initials: M
authors.lastname: Sugaya
authors.forename: H
authors.initials: H
authors.lastname: Suga
authors.forename: S
authors.initials: S
authors.lastname: Morimura
authors.forename: M
authors.initials: M
authors.lastname: Kamata
authors.forename: H
authors.initials: H
authors.lastname: Ohmatsu
authors.forename: H
authors.initials: H
authors.lastname: Fujita
authors.forename: Y
authors.initials: Y
authors.lastname: Asano
authors.forename: Y
authors.initials: Y
authors.lastname: Tada
authors.forename: T
authors.initials: T
authors.lastname: Kadono
authors.forename: S
authors.initials: S
authors.lastname: Sato
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D054414:Chemokine CCL17 / Q000097:blood* / Q000378:metabolism; D003876:Dermatitis, Atopic / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D018819:Dipeptidyl Peptidase 4 / Q000097:blood* / Q000378:metabolism; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D016410:Lymphoma, T-Cell, Cutaneous / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D012995:Solubility
chemical_list: D015415:Biomarkers; D054414:Chemokine CCL17; D018819:Dipeptidyl Peptidase 4