title: Increased interleukin 5 production in eosinophilic Sézary syndrome: regulation by interferon alfa and interleukin 12.
abstract: BACKGROUND
  Peripheral eosinophilia occurs in a small subpopulation of patients with cutaneous T-cell lymphoma (CTCL) and denotes a poor prognosis. Clinical studies have suggested that the Sézary cell is a T(H)2 type helper T cell that produces cytokines that enhance the differentiation and activation of eosinophils. Interferon alfa (IFN-alpha) and interleukin 12 are effective therapeutic agents for CTCL and other hematologic disorders.
  
  
  OBJECTIVE
  Our purpose was to determine the inhibitory activity of IFN-alpha and IL-12 on IL-5 production in vitro by peripheral blood mononuclear cells (PBMCs) obtained from patients with CTCL and eosinophilia.
  
  
  METHODS
  Suppression of IL-5 production by IFN-alpha and IL-12 was assessed by comparing IL-5 production by PBMCs from patients with Sézary syndrome and eosinophilia when cultured alone or in the presence of either IFN-alpha or IL-12.
  
  
  RESULTS
  A marked increase in IL-5 production by PBMCs from patients with Sézary syndrome and eosinophilia was observed. IL-5 production was markedly reduced when PBMCs were exposed to IFN-alpha or IL-12.
  
  
  CONCLUSIONS
  These results suggest that IFN-alpha and perhaps IL-12 may produce a therapeutic response in patients with CTCL and eosinophilia through direct suppression of IL-5 production by malignant Sézary cells.
authors.affiliation: Department of Dermatology and the General Clinical Research Center of the Hospital of the University of Pennsylvania, Philadelphia 19104-4283, USA.
authors.forename: K R
authors.initials: KR
authors.lastname: Suchin
authors.forename: M
authors.initials: M
authors.lastname: Cassin
authors.forename: S L
authors.initials: SL
authors.lastname: Gottleib
authors.forename: S
authors.initials: S
authors.lastname: Sood
authors.forename: A J
authors.initials: AJ
authors.lastname: Cucchiara
authors.forename: E C
authors.initials: EC
authors.lastname: Vonderheid
authors.forename: A H
authors.initials: AH
authors.lastname: Rook
mesh_terms: D002478:Cells, Cultured; D004802:Eosinophilia / Q000097:blood / Q000276:immunology; D006801:Humans; D007370:Interferon Type I / Q000494:pharmacology*; D018664:Interleukin-12 / Q000494:pharmacology*; D015848:Interleukin-5 / Q000096:biosynthesis*; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins; D012751:Sezary Syndrome / Q000276:immunology*; D012878:Skin Neoplasms / Q000276:immunology*
chemical_list: D007370:Interferon Type I; D015848:Interleukin-5; D011994:Recombinant Proteins; D018664:Interleukin-12