TLR4 and amyotrophic lateral sclerosis: Receptors of the innate immune response could be potential sensors of molecules that induce or amplify inflammation in ALS (Letiembre et al., 2009), given that CD14, a protein facilitating TLR4 responses to lipopolyssaccharides (LPS), and TLR2 are upregulated in the spinal cords of mouse models (Nadeau and Rivest, 2000; Nguyen et al., 2001) and ALS patients (Letiembre et al., 2009; Liu et al., 2009).