title: Transdermal photodynamic therapy--a treatment option for rheumatic destruction of small joints?
abstract: OBJECTIVE
  Synovectomy of small joints is a therapeutic approach in patients suffering from rheumatoid arthritis (RA). We examined the feasibility of transdermal photodynamic therapy (tPDT) in a fibroblast-induced model of joint destruction using the novel photosensitizer (PS) tetrahydroporphyrin-tetratosylat that shows strong absorption at the near infra-red spectral region.
  
  
  METHODS
  The functionality of the PDT system was assessed in vitro. Following arthritis induction and PS application, tPDT was applied in vivo. Therapy results were evaluated by measuring joint swelling, serum amyloid A (SAA) and histologically.
  
  
  RESULTS
  We were able to present a fully functional PDT in vitro. The in vivo therapy modalities were well tolerated by mice. We could demonstrate photodynamic ablation of subcutaneously located tissue (skeletal muscle) without skin damage.
  
  
  CONCLUSIONS
  This study provides the basis for transdermal accessibility of tissue through a photodynamic process which may serve as a minimally invasive synovectomy strategy.
authors.affiliation: Institute of Pathology, University Hospital Heidelberg, 69121 Heidelberg, Germany. benjamin.funke@med.uni-heidelberg.de
authors.forename: Benjamin
authors.initials: B
authors.lastname: Funke
authors.forename: Astrid
authors.initials: A
authors.lastname: Jungel
authors.forename: Stanislaw
authors.initials: S
authors.lastname: Schastak
authors.forename: Katharina
authors.initials: K
authors.lastname: Wiedemeyer
authors.forename: Frank
authors.initials: F
authors.lastname: Emmrich
authors.forename: Ulrich
authors.initials: U
authors.lastname: Sack
mesh_terms: D000818:Animals; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001169:Arthritis, Experimental / Q000188:drug therapy; D001172:Arthritis, Rheumatoid / Q000188:drug therapy; D015415:Biomarkers / Q000097:blood; D002460:Cell Line; D004195:Disease Models, Animal; D005240:Feasibility Studies; D005260:Female; D005978:Glutathione / Q000187:drug effects / Q000378:metabolism; D008027:Light; D051379:Mice; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use; D011166:Porphyrins / Q000627:therapeutic use; D012216:Rheumatic Diseases / Q000097:blood / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D012699:Serology; D000685:Serum Amyloid A Protein / Q000187:drug effects / Q000378:metabolism; D016511:Severe Combined Immunodeficiency / Q000188:drug therapy
chemical_list: D018501:Antirheumatic Agents; D015415:Biomarkers; D017319:Photosensitizing Agents; D011166:Porphyrins; D000685:Serum Amyloid A Protein; C519279:tetrahydroporphyrin tetratosylate; D005978:Glutathione