RT Journal Article
SR Electronic
T1 IL32 expression in induced sputum of COPD subjects
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P596
VO 42
IS Suppl 57
A1 Maria Cristina Scarpa
A1 Kim Lokar Oliani
A1 Filippo Liviero
A1 Simonetta Baraldo
A1 Graziella Turato
A1 Fiorella Calabrese
A1 Marina Saetta
A1 Piero Maestrelli
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/P596.abstract
AB IL32 is a cytokine produced by T lymphocytes, natural killers cells, lung epithelial cells, monocytes and macrophages, involved in some chronic inflammatory diseases characterized by an autoimmune pathogenesis. A recent study demonstrated increased expression of IL32 in peripheral lung of COPD subjects.The present research investigated whether induced sputum, being a non-invasive methods, could be useful to study IL32 expression levels in COPD subjects.Sputum was induced in 20 COPD patients, 20 smokers without airflow limitation, 20 non-smokers with normal respiratory function and 20 systemic sclerosis (SS) subjects, as disease control. IL32 expression was evaluated by immunocytochemistry. Immunoreactivity was quantified in alveolar macrophages as a score obtained multiplying the % of positive cells for the staining intensity (0-3). The mRNA for IL32 isoform α, β and ε was evaluated by RT-PCR.Adequate number of macrophages for immunocytochemistry was obtained in 50% COPD subjects only. Macrophages % was decreased significantly in COPD subjects (median 19, [interquartile range: 9.4-29.2]) compared to smokers (52.2, [23.3-66.7], p<0.01), non-smokers (50.8, [44.5-63.2], p<0.01) and SS subjects (49.9, [32.9-69.4], p<0.01). IL32 score was not different among the four groups: COPD (150, [15-300]), SS subjects (80, [30-160]), smokers (160, [6-292]) and non-smokers (160, [95-235]). Unlike lung tissue samples, IL32 α isoform was never detected in COPD patients. While the β isoform was observed in all sputum samples, the ε isoform was detected in 54% of COPD subjects, 27% of smokers and 50% of non-smokers.In conclusion, IL32 expression in induced sputum samples do not reflect that observed in peripheral lung tissue.