Consistently up-regulated macrophage activation genes in 9 V/null and 4L mice. The expression values of each consistently (≥2 time points from 12 to 28 wk) up-regulated macrophage activation genes in the lung (Lu) and liver (Lv) of 9 V/null and 4L mice were plotted on the ordinate. The mean expression values (fold-change) of these genes in each tissue are indicated by a horizontal bar. The numbers of these genes were 96/119 (81%) or 15/21 (71%) in 9 V/null lung or liver, respectively; and 43/83 (52%) or 14/21 (67%) in 4L lung or liver, respectively (Additional file 3). The median fold change for these gene expression values in 9 V/null lung and liver were higher than in the corresponding 4L tissues.