Human and mouse gene expression data from LPS-exposed mouse lungs treated with human MSCs

Multipotent stromal cells (MSCs) are currently in clinical trials for a number of inflammatory diseases. Recent studies have demonstrated the ability of MSCs to attenuate inflammation in rodent models of acute lung injury (ALI) suggesting that MSCs may also be beneficial in treating ALI. To better understand how human MSCs (hMSCs) may act in ALI, the lungs of immunocompetent mice were exposed to lipopolysaccharide (LPS) and 4 hr later bone marrow derived hMSCS were delivered by oropharyngeal aspiration (OA). Administration of hMSCs significantly reduced the expression of pro-inflammatory cytokines, neutrophil counts and total protein in bronchoalveolar lavage. There was a concomitant reduction in pulmonary edema as indicated by a decrease in lung wet/dry weight ratio. The anti-inflammatory effects of hMSCs were not dependent on localization to the lung, as intraperitoneal administration of hMSCs also attenuated LPS-induced inflammation in the lung. Microarray analysis revealed significant induction of TNF--induced protein 6 (TSG-6) expression by hMSCs 12 hr after OA delivery to LPS-exposed lungs. Knockdown of TSG-6 expression in hMSCs by RNA interference abrogated most of their anti-inflammatory effects. In addition, intra-pulmonary delivery of recombinant human TSG-6 reduced LPS-induced inflammation in the lung. These results show that hMSCs recapitulate the observed beneficial effects of rodent MSCs in animal models of ALI and suggest that the anti-inflammatory properties of hMSCs in the lung are explained, at least in part, by activation of hMSCs to secrete TSG-6.

10