There are four major findings in the present study regarding administration of the MSC-CM following LPS-induced ALI: (i) the number and activity of neutrophils in the lungs were reduced; (ii) levels of IL-6, MIP-2, NF-κB p65, and phospho-NF-κB p65 were reduced; (iii) expression levels of Bcl-xL and Mcl-1 were reduced and neutrophil apoptosis was affected; and (iv) lower levels of NF-kB and MMP-9 activity were detected in human neutrophils that were isolated from the peripheral blood of patients with ARDS and treated with LPS + hMSC-CM. The gene discussed is MMP9; the disease is acute respiratory distress syndrome.