title: Identification of clonal T cells in the blood of patients with systemic sclerosis: positive correlation with response to photopheresis.
abstract: OBJECTIVE
  To search for circulating clonal T-cell populations in patients with systemic sclerosis (SSc), and to determine whether T-cell clonality in the blood predicts therapeutic response to photopheresis.
  
  
  METHODS
  Analysis of clonal T-cell receptor gamma gene rearrangements before photopheresis treatment and blinded clinical evaluation of cutaneous response to photopheresis in a case series.
  
  
  METHODS
  University hospital setting.
  
  
  METHODS
  Thirteen consecutive patients with SSc.
  
  
  METHODS
  Photopheresis in 11 patients.
  
  
  METHODS
  Clonality of T cells in the blood before photopheresis and clinical response to photopheresis.
  
  
  RESULTS
  Screening of blood samples from 13 SSc patients for clonal T-cell receptor gamma gene rearrangements revealed a monoclonal T cell population in 6 (46%) of 13 SSc patients. Clinical response to photopheresis in 11 patients was evaluated in a blinded manner using skin severity scores. Clonality of T cells appeared to be associated with a higher chance of response to photopheresis therapy, as 4 (67%) of 6 patients in the clone-positive group vs 1 (20%) of 5 in the clone-negative group experienced a clinically significant response to treatment.
  
  
  CONCLUSIONS
  A high proportion of patients with SSc have detectable expanded clonal T-cell populations in the peripheral blood, and such patients appear more likely to respond to photopheresis.
authors.affiliation: Department of Dermatology, Geneva University Hospital, 24, rue Micheli-du-Crest, CH-1211 Genève 14 Switzerland. french@cmu.unige.ch
authors.forename: L E
authors.initials: LE
authors.lastname: French
authors.forename: S R
authors.initials: SR
authors.lastname: Lessin
authors.forename: K
authors.initials: K
authors.lastname: Addya
authors.forename: B
authors.initials: B
authors.lastname: Denardo
authors.forename: D J
authors.initials: DJ
authors.lastname: Margolis
authors.forename: D G
authors.initials: DG
authors.lastname: Leonard
authors.forename: A H
authors.initials: AH
authors.lastname: Rook
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D006801:Humans; D007963:Leukocytes, Mononuclear; D008297:Male; D008875:Middle Aged; D017893:Photopheresis; D016133:Polymerase Chain Reaction; D012595:Scleroderma, Systemic / Q000097:blood* / Q000188:drug therapy*; D012720:Severity of Illness Index; D016896:Treatment Outcome