title: Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL): a possible pathogenic role in chronic plaque psoriasis.
abstract: BACKGROUND
  Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a cytokine member of the tumour necrosis factor (TNF) family. Its role has been investigated in skin cancers and some inflammatory and/or immune-mediated skin diseases. An involvement of TRAIL in psoriasis pathogenesis has recently been hypothesized. We investigated the expression and localization of TRAIL and its receptors in psoriatic skin and measured serum TRAIL. The intracellular pathways activated by TRAIL were assessed to investigate its potential role in the pathogenesis of psoriasis.
  
  
  METHODS
  Twenty-four consecutive patients with plaque psoriasis and age- and sex-matched healthy subjects were recruited. Serum TRAIL was measured by means of an enzyme-linked immunosorbent assay (ELISA). TRAIL and TRAIL receptors were evaluated by reverse transcription - polymerase chain reaction (RT-PCR) (RNA of lesional and non-lesional psoriatic skin) and by immunohistochemistry (lesional skin). Caspase 8 and NF-kB immunoexpression were also evaluated by immunohistochemistry.
  
  
  RESULTS
  RT-PCR demonstrated increased synthesis of TRAIL and its receptors in lesional vs. non-lesional skin. Immunohistochemistry showed a strong staining of TRAIL and TRAIL receptors both in the epidermis and in the dermal infiltrate. Finally, a correlation emerged between caspase 8 and TRAIL immunoexpression in the dermis.
  
  
  CONCLUSIONS
  Our findings suggest an involvement of TRAIL in psoriasis pathogenesis, probably through an action at the site of the inflammatory infiltrate, likely via caspase 8.
authors.affiliation: Institute of Dermatology, "Sacro Cuore" Catholic University, Rome, Italy - giacomocaldarola@libero.it.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Caldarola
authors.forename: Angelo
authors.initials: A
authors.lastname: Carbone
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Arena
authors.forename: Ilaria
authors.initials: I
authors.lastname: Pennacchia
authors.forename: Chiara
authors.initials: C
authors.lastname: De Waure
authors.forename: Giovina
authors.initials: G
authors.lastname: Vianale
authors.forename: Franco
authors.initials: F
authors.lastname: Scaldaferri
authors.forename: Magda
authors.initials: M
authors.lastname: D'Agostino
authors.forename: Francesco
authors.initials: F
authors.lastname: Valenzano
authors.forename: Erica
authors.initials: E
authors.lastname: Costantini
authors.forename: Matteo
authors.initials: M
authors.lastname: Auriemma
authors.forename: Paolo
authors.initials: P
authors.lastname: Amerio
authors.forename: Clara
authors.initials: C
authors.lastname: De Simone
mesh_terms: D000328:Adult; D017209:Apoptosis; D015415:Biomarkers / Q000097:blood; D001706:Biopsy; D016022:Case-Control Studies; D053181:Caspase 8 / Q000097:blood*; D020405:Dermis / Q000473:pathology; D004817:Epidermis / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011565:Psoriasis / Q000097:blood / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D012680:Sensitivity and Specificity; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000097:blood*
chemical_list: D015415:Biomarkers; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D053181:Caspase 8