Fig. 2
Effects of M. ovipneumoniae infections on the production of MDA and SOD in sheep airway epithelial cells. Sheep airway epithelial cells cultured on an air-liquid interface model were apically infected with 1, 10 and 100 MOI of M. ovipneumoniae (MO) at 37 °C for 24 h, the levels of MDA and SOD were measured using appropriate kits. a A dose-dependent increase of MDA production was observed in cells infected with MO. b A dose-dependent decrease of total-SOD (T-SOD) level of airway epithelial cells was induced by the MO infection. c A significant increase in the MDA/SOD ratio in sheep airway epithelial cells infected with MO. d A representative image of immunoblot showing the reduced expression of Mn-SOD protein in ALI cultures infected with MO (MOI = 100) (top panel) compared with the uninfected cells, which was significantly different as determined based on the value of densitometric arbitrary units (A.U.) calculated as the densitometric signal of Mn-SOD protein over that of the corresponding β-actin internal control (bottom panel). Data were expressed as the means ± SD from three independent experiments, and each experimental had six replicated ALI cultures (N = 18) in a–c. Compared with the uninfected controls, *: p < 0.05; **: p < 0.01. The cell numbers of each transwell with diameter of 24 mm was determined as 107