SLC7A11 and serum lipopolysaccharide activity: In an experimental endotoxemia mouse model, xCT mRNA was constitutively expressed in the brain, thymus, and spleen, and xCT mRNA was strongly upregulated in thymus and spleen following administration of a sublethal dose of LPS, indicating that xCT plays an important role during the host inflammatory response to bacterial infection in vivo (Taguchi et al., 2007).