CD4~+ T cells from behcet patients produce high levels of IL-17

Purpose:To investigate the role of interleukin (IL)-17-producing CD4+ T cells in Behcet disease (BD).Methods:Blood samples were drawn from eight BD patients with active uveitis,eight BD patients with inactive uveitis and eight normal controls,respectively.PBMCs were prepared from heparinized blood by Ficoll-Hypaque density-gradient centrifugation.Peripheral CD4+ T cells were purified by Human CD4 Microbeads.(MACS).The purity rate of CD4+ T cells was detected using flow cytometry.Purified CD4+ T cells were stimulated with or without anti-CD3 and anti-CD28 antibodies in the presence or absence of recombinant-IL-23 (rIL-23) or recombinant-IL-12 (rIL-12) for 72 hours.The concentrations of IL-17,IFN-γ and IL-4 in the collected supernatants from CD4+ T cells were measured using a Duoset ELISA Development kit.Results:The results showed that the levels of IL-17 and IFN-γ observed in active BD patients were significantly higher as compared with those in inactive patients and normal controls.There was no significant difference concerning IL-4 production between BD patients and normal controls.rIL-23 significantly augmented the production of IL-17 by CD4+ T cells from both BD patients and normal controls.Both rIL-23 and rIL-12 could increase IFN-γ production by CD4+ T cells from BD patients and normal controls.Moreover,the effect of rIL-12 was more robust compared with that of rIL-23.Neither rIL-23 nor rIL-12 exerted any effect on IL-4 production.Conclusion:rIL-23 can promote the production of IL-17 by CD4+ T cells in BD patients.The upregulated IL-17 levels may be related with the intraocular inflammation of Behcet patients.