CXCL11 in bronchoalveolar lavage fluid and pulmonary function decline in systemic sclerosis.

OBJECTIVES: Several studies have focused on the antifibrotic potential of the Th1 cytokine IFN-γ-1b through suppression of Th2 fibrogenic functions. It has been reported that IFN-γ induces the production of CXCL11 in the lung and plasma of patients with lung-fibrosis. The aim of the present study was to determine whether the levels of CXCL11 in the bronchoalveolar lavage fluid (BALF) of SSc patients might be a predictor of clinically significant fibrotic lung involvement.

METHODS: In a retrospective longitudinal study we analysed BALF samples from 16 SSc patients with interstitial lung disease (ILD) and 16 matched control patient without ILD. Patients were eligible if they did not have evidence of ILD at the time of BAL as shown by HRCT. A standard morphological and immunological analysis of BALF cellular components was performed. CXCL11 was measured in BALF by specific ELISA assay.

RESULTS: BALF CXCL11 concentrations were significantly elevated in the samples taken from patients who did not developed ILD as compared to those who developed ILD (p<0.001). Stepwise logistic regression analysis revealed that BALF CXCL11 levels predicted clinically significant ILD (p<0.001).

CONCLUSIONS: The presence of elevated BALF concentrations of CXCL11 in SSc patients who do not developed lung fibrosis suggest that determination of CXCL11 in BALF could serve as a prognostic factor for pulmonary function decline.