To determine the effect of RNase L on the development of ALI, the differential expression of certain pro- and anti-inflammatory genes such as TNF-α, IL-1β, IL-4, IL-6, IL-10, and Cox-2 in the lung tissues and blood from RNase L wild type and knock out mice after LPS administration was examined by ELISA and Western blot analyses. This evidence concerns the gene RNASEL and acute respiratory distress syndrome.