title: IL-2, IL-5, TNF-α and IFN-γ mRNA expression in epidermal keratinocytes of systemic lupus erythematosus skin lesions.
abstract: OBJECTIVE
  To analyze cytokine gene expression in keratinocytes from patients with systemic lupus erythematosus (SLE).
  
  
  BACKGROUND
  Keratinocytes represent 95% of epidermal cells and can secrete several cytokines.
  
  
  METHODS
  Keratinocytes were obtained by laser microdissection from 21 patients with SLE (10 discoid and 11 acute lesions) at involved and uninvolved sites. All patients were receiving a low/moderate prednisone dose and 18 were receiving chloroquine diphosphate. IL-2, IL-5, TNF-α and IFN-γ gene expression was evaluated by real-time PCR and expressed as the ratio (R) to a pool of skin samples from 12 healthy volunteers.
  
  
  RESULTS
  Heterogeneity in cytokine gene expression was found among patients with SLE. Eighteen of 38 valid SLE samples (47%) presented overexpression (R>1) of at least one cytokine. Lesional skin samples tended to show higher cytokine expression than samples from uninvolved skin (p = 0.06). IL-5 and IFN-γ were the most commonly overexpressed cytokines. Samples with cytokine overexpression corresponded to more extensive and severe lesions. Prednisone dose did not differ between samples without cytokine overexpression (15.71±3.45 mg/day) and those with overexpressed cytokines (12.68±5.41 mg/day) (p = 0.216). Samples from all patients not receiving diphosphate chloroquine had at least one overexpressed cytokine.
  
  
  CONCLUSIONS
  The heterogeneous keratinocyte cytokine gene expression reflects the complex immunological and inflammatory background in SLE. Patients with severe/extensive skin lesions showed a higher frequency of cytokine gene overexpression. Increased IFN-γ and IL-5 expression suggests that Th1 and Th2 cells are involved in SLE skin inflammation. The possibility that prednisone and antimalarial drugs may have contributed to low cytokine gene expression in some samples cannot be ruled out.
authors: Universidade Federal do Pará, Belém, PA, Brasil.
authors: José Ronaldo M
authors: JR
authors: Carneiro
authors: Hellen T
authors: HT
authors: Fuzii
authors: Cristiane
authors: C
authors: Kayser
authors: Fernando L
authors: FL
authors: Alberto
authors: Fernando A
authors: FA
authors: Soares
authors: Emília I
authors: EI
authors: Sato
authors: Luís Eduardo C
authors: LE
authors: Andrade
mesh_terms: D000328:Adult; D016207:Cytokines / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism*; D008180:Lupus Erythematosus, Systemic / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D012871:Skin Diseases / Q000235:genetics* / Q000378:metabolism; D055815:Young Adult
chemical_list: D016207:Cytokines; D012333:RNA, Messenger