title: CD26/dipeptidyl-peptidase IV and adenosine deaminase serum levels in psoriatic patients treated with cyclosporine, etanercept, and psoralen plus ultraviolet A phototherapy.
abstract: OBJECTIVE
  The aim of this study is to determine serum levels of soluble forms of CD26/dipeptidyl-peptidase IV (DPP-IV) and adenosine deaminase (ADA), thought to be markers of T-cell activation, and changes in their levels in response to cyclosporine, etanercept, and psoralen plus ultraviolet A (PUVA) treatments with respect to disease activity.
  
  
  METHODS
  This study is designed as a prospective clinical study with a control group and three months of follow-up. The study included 41 patients with psoriasis and 41 healthy controls that were older than 18years of age. There were three different treatment groups: PUVA (n=15), cyclosporine (n=15), and etanercept (n=11). To determine disease severity of patients with psoriasis, psoriasis area and severity index (PASI) scores were calculated.
  
  
  RESULTS
  Only mean serum ADA levels were different between patients with psoriasis [mean1±standard deviation (SD)=13.9±3.3U/ml] and control group (mean±SD=12±3.5U/ml). Mean serum ADA levels were significantly higher before treatment than after treatment (mean±SD=12.4±3.4U/ml). Contrarily, following three months of therapy, mean serum CD26 levels increased significantly from 777.7±214.6 to 835.3±203ng/ml (P<0.05) and mean serum DPP-IV activity increased significantly from 12.1±4 to 15.9±4.2nmol/min (P<0.05). There was no correlation between ADA and CD 26/DPP-IV with PASI values.
  
  
  CONCLUSIONS
  The results show that ADA might be a useful marker indicating disease activity and T-cell activation. As significant changes were observed in serum CD26/DPP-IV before and after treatment, we think CD26/DPP-IV might play a role in psoriasis pathogenesis, which should be clarified by further studies.
authors.affiliation: Department of Dermatology, Faculty of Medicine, Hacettepe University, Ankara, Turkey. felifd@hacettepe.edu.tr
authors.forename: Fatma Elif
authors.initials: FE
authors.lastname: Yıldırım
authors.forename: Ayşen
authors.initials: A
authors.lastname: Karaduman
authors.forename: Asli
authors.initials: A
authors.lastname: Pinar
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Aksoy
mesh_terms: D000243:Adenosine Deaminase / Q000097:blood*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D016572:Cyclosporine / Q000008:administration & dosage*; D018819:Dipeptidyl Peptidase 4 / Q000097:blood*; D000068800:Etanercept; D005260:Female; D005363:Ficusin / Q000008:administration & dosage; D006801:Humans; D007074:Immunoglobulin G / Q000008:administration & dosage*; D007166:Immunosuppressive Agents / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011446:Prospective Studies; D011565:Psoriasis / Q000097:blood / Q000188:drug therapy / Q000532:radiotherapy; D018124:Receptors, Tumor Necrosis Factor / Q000008:administration & dosage*; D014467:Ultraviolet Therapy; D055815:Young Adult
chemical_list: D015415:Biomarkers; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D017319:Photosensitizing Agents; D018124:Receptors, Tumor Necrosis Factor; D016572:Cyclosporine; C042807:DPP4 protein, human; D018819:Dipeptidyl Peptidase 4; C548482:ADA protein, human; D000243:Adenosine Deaminase; D005363:Ficusin; D000068800:Etanercept