RT Journal Article SR Electronic T1 Peripheral blood myeloid-derived suppressor cells reflect disease status in idiopathic pulmonary fibrosis JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP ERJ-01826-2015 DO 10.1183/13993003.01826-2015 A1 Isis E. Fernandez A1 Flavia R. Greiffo A1 Marion Frankenberger A1 Julia Bandres A1 Katharina Heinzelmann A1 Claus Neurohr A1 Rudolf Hatz A1 Dominik Hartl A1 Jürgen Behr A1 Oliver Eickelberg YR 2016 UL http://erj.ersjournals.com/content/early/2016/08/31/13993003.01826-2015.abstract AB Idiopathic pulmonary fibrosis (IPF) is a fibroproliferative disease with irreversible lung function loss and poor survival. Myeloid-derived suppressor cells (MDSC) are associated with poor prognosis in cancer, facilitating immune evasion. The abundance and function of MDSC in IPF is currently unknown.Fluorescence-activated cell sorting was performed in 170 patients (IPF: n=69; non-IPF interstitial lung disease (ILD): n=56; chronic obstructive pulmonary disease (COPD): n=23; healthy controls: n=22) to quantify blood MDSC and lymphocyte subtypes. MDSC abundance was correlated with lung function, MDSC localisation was performed by immunofluorescence. Peripheral blood mononuclear cell (PBMC) mRNA levels were analysed by qRT-PCR.We detected increased MDSC in IPF and non-IPF ILD compared with controls (30.99±15.61% versus 18.96±8.17%, p≤0.01). Circulating MDSC inversely correlated with maximum vital capacity (r= −0.48, p≤0.0001) in IPF, but not in COPD or non-IPF ILD. MDSC suppressed autologous T-cells. The mRNA levels of co-stimulatory T-cell signals were significantly downregulated in IPF PBMC. Importantly, CD33+CD11b+ cells, suggestive of MDSC, were detected in fibrotic niches of IPF lungs.We identified increased MDSC in IPF and non-IPF ILD, suggesting that elevated MDSC may cause a blunted immune response. MDSC inversely correlate with lung function only in IPF, identifying them as potent biomarkers for disease progression. Controlling expansion and accumulation of MDSC, or blocking their T-cell suppression, represents a promising therapy in IPF.Circulating myeloid-derived suppressor cells are increased in IPF and inversely correlate with lung function http://ow.ly/6rDm301BpvC