title: Monocytes and T lymphocytes contribute to a predominance of interleukin 6 and interleukin 10 in systemic lupus erythematosus.
abstract: OBJECTIVE
  To investigate the contribution of T lymphocytes and monocytes to cytokine production in systemic lupus erythematosus (SLE).
  
  
  METHODS
  Forty-five SLE patients and 19 healthy volunteers were included. Serum levels of tumor necrosis factor alpha (TNFalpha), interferon gamma (IFN gamma), interleukin (IL)-6, and IL10 were quantified by ELISA. The cytokine production capacities of peripheral blood mononuclear cells were assessed by culturing in vitro with PMA+Ionomycin or LPS. The intracellular cytokine expression was measured by flow cytometry in T lymphocytes and monocytes, respectively. The influence of the disease activity (measured as the SLE-disease activity index; SLEDAI) and the treatment the patients were receiving was evaluated.
  
  
  RESULTS
  Serum IL10, IL6, and TNFalpha levels were increased in patients (P <or= 0.01), and a higher spontaneous (without stimuli) intracellular expression of IL10 in CD4+ and CD8+ T lymphocytes (P < 0.05) and of IL6 in monocytes (P = 0.01) were found. After stimulation, patients presented a higher percentage of CD4+ and CD8+ T lymphocytes producing IL4 and IL10 (P <or= 0.01), and of monocytes producing IL6 (P = 0.04) and IL10 (P = 0.008). The SLEDAI score was positively correlated with the percentage of CD4+IL10+ and CD8+IL10+ T lymphocytes (P < 0.01), and inversely correlated with CD8+TNFalpha+ (P= 0.02), CD4+IFN gamma+ (P = 0.04) and CD8+ IFN gamma+ (P = 0.002) T lymphocytes. Patients receiving high dose prednisone produced higher IL10, but they also were the patients with a more active disease.
  
  
  CONCLUSIONS
  Monocytes and T lymphocytes (CD4+ and CD8+) contribute to an overproduction of IL6 and IL10 in SLE; this correlates with the disease activity but is independent of the treatment the patients are receiving.
authors.affiliation: Servicio de Medicina Interna, Hospital Universitario Puerta de Hierro Majadahonda, Departamento de Medicina, Universidad Autónoma de Madrid, Madrid, Spain. susanamellor@hotmail.com
authors.forename: Susana
authors.initials: S
authors.lastname: Mellor-Pita
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Citores
authors.forename: Raquel
authors.initials: R
authors.lastname: Castejon
authors.forename: Miguel
authors.initials: M
authors.lastname: Yebra-Bango
authors.forename: Pablo
authors.initials: P
authors.lastname: Tutor-Ureta
authors.forename: Silvia
authors.initials: S
authors.lastname: Rosado
authors.forename: Jose L
authors.initials: JL
authors.lastname: Andreu
authors.forename: Juan A
authors.initials: JA
authors.lastname: Vargas
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood / Q000378:metabolism; D016753:Interleukin-10 / Q000097:blood / Q000378:metabolism*; D015850:Interleukin-6 / Q000097:blood / Q000378:metabolism*; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology* / Q000378:metabolism / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism / Q000473:pathology*; D013601:T-Lymphocytes / Q000378:metabolism / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000378:metabolism; D055815:Young Adult
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D007371:Interferon-gamma