Evaluation of Th17-related cytokines and IFNγ production from blood mononuclear cells of moderate and severe asthmatic children reveals methylprednisolone does not decrease IL-22 levels.

ABSTRACT

OBJECTIVE: The aim of this study was to correlate IL-6, IL-17A, IFNγ, and IL-22 production with asthma disease severity and to evaluate if methylprednisolone downregulated cytokine production in peripheral blood mononuclear cells (PBMCs). METHODS: Forty-two children with chronic persistent asthma and 34 non-asthmatic children were selected. Cytokines were quantified by ELISA from serum or PBMCs supernatants, after the PMA and Ionomycin stimulation, with or without methylprednisolone at 100 µM. RESULTS: Our data showed undetectable levels of serum cytokines in most patients and controls. In the PBMCs, we have observed a higher production of IL-17A than IL-22 among asthmatics and controls, although it is not statistically significant. IL-6, IFNγ, and IL-17A levels were significantly reduced after methylprednisolone treatment (p = 0.02, 0.03, and 0.03, respectively) in Severe Persistent Asthma (SPA) and in Moderate Persistent Asthma (MPA), (p = 0.007, 0.01, and 0.007, respectively). However, IL-22 levels were unaffected (SPA, p = 0.12 and MPA, p = 0.93). CONCLUSION: Methylprednisolone downregulated IL-6, IL17A, and IFNγ, but not IL-22, in stimulated PBMCs from asthmatic children indicating that methylprednisolone has no effect on IL-22 production by PBMCs.