Abstract
Recently, the presence of inflammatory cells expressing IL-17A has been reported in the small airway subepithelium obtained from COPD patients (Eustace A et al. Chest. 2010) which, with further evidence (reviewed in Alcorn JF et al. Annu Rev Physiol. 2010), suggests that Th17 immune response may participate in COPD pathomechanisms. However, to date there has been no data about the presence of IL-17A and Th17 associated cytokines in bronchoalveolar (BAL) cells from COPD patients.
We therefore explored the mRNA expression of key cytokines (IL-17A, IL-17F, IL-21, IL-22 and IL-23) associated with Th 17 immune response in BAL cells from COPD patients (n=27; GOLD stage I=4, stage II=18, stage III-IV=5) and the control subjects (n=25) using quantitative RT-PCR (PSMB2 as a denominator).
Expression profiling did not reveal differences in mRNA expression of IL-17A and other products of Th17 cells (IL-17F, IL-21 and IL-22) between COPD patients and the control subjects (p>0.05). However, an activator of Th17 cells, a cytokine IL-23, was upregulated in BAL cells from COPD patients (median of relative expression IL-23/PSMB2: patients, 0.07; controls, 0.02; p=0.001).
In conclusion, we show here that IL-23 transcripts are present in unseparated BAL cells from COPD patients. Characterisation of the cell source and of possible functional significance of IL-23 for Th17 mediated immune response will be subject of further investigations.
Support: IGA MZ CR NS/10267-3, IGA UP LF_2010_008
- © 2011 ERS