title: IL-17A and IL-17F expression in B lymphocytes.
abstract: BACKGROUND
  Recent evidence suggests that cells other than Th-17 lymphocytes express interleukin (IL)-17A and IL-17F and contribute to the production of these cytokines in immunologically mediated diseases. B lymphocytes are known to be an important source of cytokines in chronic inflammatory diseases. We therefore investigated the potential of human B lymphocytes to produce IL-17A and IL-17F.
  
  
  METHODS
  Highly purified B cells were obtained using a multiple-step separation procedure which included rosette depletion, adherence depletion, CD3+ cell magnetic activated depletion and CD19+ magnetic activated positive cell selection. In these CD19+ B cell fractions, CD3+/CD4+ and CD14+ cells were negligible (<0.2%), and CD8 and CD161 mRNAs were undetectable. The CD19+/CD20+ B cells were stimulated with IL-4, interferon-γ, IL-6, IL-23 and transforming growth factor (TGF)-β, and the expression of IL-17A and IL-17F in response to stimulation was determined by quantitative reverse transcription (RT)-PCR, Western blot, immunocytochemistry and ELISA.
  
  
  RESULTS
  Evidence of expression of IL-17A and IL-17F in purified B cells was obtained using RT-PCR, flow cytometry, immunofluorescence microscopy, Western immunoblotting and ELISA. Stimulation of B cells with IL-6, IL-23 or TGF-β upregulated the expression of both IL-17A and F cytokines.
  
  
  CONCLUSIONS
  These novel findings provide evidence that cytokine-stimulated B lymphocytes could be a significant source of IL-17A and IL-17F and support the notion that these cells actively participate in immune responses via alternative mechanisms in addition to the classic release of antibodies.
authors: Asthma Research Chair, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
authors: Alejandro
authors: A
authors: Vazquez-Tello
authors: Rabih
authors: R
authors: Halwani
authors: Rui
authors: R
authors: Li
authors: Jessica
authors: J
authors: Nadigel
authors: Amir
authors: A
authors: Bar-Or
authors: Bruce D
authors: BD
authors: Mazer
authors: David H
authors: DH
authors: Eidelman
authors: Saleh
authors: S
authors: Al-Muhsen
authors: Qutayba
authors: Q
authors: Hamid
mesh_terms: D015703:Antigens, CD / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007114:Immunization; D018189:Immunomagnetic Separation; D020381:Interleukin-17 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008297:Male; D014066:Palatine Tonsil / Q000473:pathology; D015854:Up-Regulation
chemical_list: D015703:Antigens, CD; D016207:Cytokines; D020381:Interleukin-17