Transdermal photodynamic therapy--a treatment option for rheumatic destruction of small joints?
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.
Funke
Benjamin
B
Institute of Pathology, University Hospital Heidelberg, 69121 Heidelberg, Germany. benjamin.funke@med.uni-heidelberg.de
Jungel
Astrid
A
Schastak
Stanislaw
S
Wiedemeyer
Katharina
K
Emmrich
Frank
F
Sack
Ulrich
U
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
D018501:Antirheumatic Agents; D015415:Biomarkers; D017319:Photosensitizing Agents; D011166:Porphyrins; D000685:Serum Amyloid A Protein; C519279:tetrahydroporphyrin tetratosylate; D005978:Glutathione