Interestingly, our previous study demonstrated that a capsular polysaccharide isolated from Klebsiella pneumonia induced ROS production and MAPK phosphorylation through TLR4 in J774A.1 macrophages; however, the inhibition of ROS by NAC did not affect the phosphorylation levels of MAPK [41]. The gene discussed is TLR4; the disease is Klebsiella pneumonia.