In vivo animal studies provide further evidence about the role of neuroimmune modulation in alcohol addiction; some studies show effects from interrupting certain neuroimmune gene expressions, such as beta-2-microglobulin and cathepsin S (Blednov et al., 2005; Blednov et al., 2012) or targeted disruption of TLR4 in the central amygdala reduced alcohol consumption (Liu et al., 2011). This evidence concerns the gene TLR4 and Addictive alcohol use.